Positions
A positions grid with signed quantities, average and mark prices, day and total P&L, a risk column you name, and totals for the displayed book.
import { useState } from "react"
import { createRowStore } from "@/lib/row-store"
import { Positions, type PositionRow } from "@/components/ui/positions"
const rows: PositionRow[] = [
{ id: "T2", book: "Cash", instrument: "T 2Y", position: 50_000_000, average: 100.25, mark: 100.28125, dayPnl: 15_625, totalPnl: 62_000, risk: 21_500 },
{ id: "T10", book: "Cash", instrument: "T 10Y", position: -25_000_000, average: 99.5, mark: 99.515625, dayPnl: -3_906, totalPnl: -12_000, risk: -21_000 },
{ id: "T30", book: "Cash", instrument: "T 30Y", position: 0, average: null, mark: 98.75, dayPnl: 0, totalPnl: null, risk: null },
]
export default function PositionsDemo() {
const [store] = useState(() => {
const store = createRowStore<PositionRow>({ getRowId: (row) => row.id })
store.applyDeltas({ upsert: rows })
return store
})
return <div className="h-48 w-fit max-w-full"><Positions store={store} label="Cash positions" riskHeader="DV01" /></div>
}
Installation
pnpm dlx shadcn@latest add tradecn/ui/positions#v1.4.13
npx shadcn@latest add tradecn/ui/positions#v1.4.13
yarn dlx shadcn@latest add tradecn/ui/positions#v1.4.13
bunx --bun shadcn@latest add tradecn/ui/positions#v1.4.13
-
Install the dependencies:
pnpm add cn @tanstack/react-virtualnpm install cn @tanstack/react-virtualyarn add cn @tanstack/react-virtualbun add cn @tanstack/react-virtual -
Add the shadcn components it composes:
pnpm dlx shadcn@latest add checkbox context-menu dropdown-menunpx shadcn@latest add checkbox context-menu dropdown-menuyarn dlx shadcn@latest add checkbox context-menu dropdown-menubunx --bun shadcn@latest add checkbox context-menu dropdown-menu -
Copy the files into your project:
components/ui/ positions.tsx import { cn } from "cn" import { useCallback, useEffect, useMemo, useRef, type ReactNode } from "react" import { directionClass, directionOf } from "@/hooks/use-flash" import { NULL_TOKEN, formatNotional, formatPrice, formatQuantity, formatSigned } from "@/lib/format" import type { RowId } from "@/lib/row-store" import { DataGrid, type ColumnDef, type DataGridProps } from "@/components/ui/data-grid" // A positions grid: the data grid with a book's columns, the position signed in the instrument's // unit, the average and the mark, the day's and the total P&L colored by their sign with the sign // printed, a risk number the consumer formats, and totals under the body. Every number is the // server's; the grid prints and adds, and works nothing out. // // One grid per book. Grouping and tree rows would cost the grid its fixed row height, which is what // makes an arrival above the first visible row move the viewport by exactly one row. export interface PositionRow { id: string book?: string instrument: string /** Signed: long above zero, short below, in the row's unit. */ position: number /** Notional by default; `contracts` prints a count. */ quantityUnit?: "notional" | "contracts" /** The average price of the position, printed through `price`. */ average?: number | null /** The mark it is carried at, printed through `price`; flashes by direction. */ mark?: number | null /** In the account's currency, as the server figures it. */ dayPnl?: number | null totalPnl?: number | null /** The desk's risk number for the row: a DV01, a delta, a beta-weighted exposure. Printed through `risk`. */ risk?: number | null } export interface PositionsColumnOptions<T extends PositionRow> { /** How to print a price for this row. Instruments differ, so it gets the row. Two decimals by default. */ price?: (value: number, row: T) => string /** How to print a P&L. Signed, no decimals, by default. */ pnl?: (value: number, row: T) => string /** How to print the risk column. Signed, no decimals, by default. */ risk?: (value: number, row: T) => string /** The risk column's header. `Risk` by default: name it what the desk calls it. */ riskHeader?: string } const twoDecimals = (value: number) => formatPrice(value, { kind: "decimal", decimals: 2 }) const wholeSigned = (value: number) => formatSigned(value, { decimals: 0 }) /** A gain printed by a formatter that drops the plus gets it back: the sign is the channel the color is not (contract rule 15). */ export function withSign(value: number, text: string): string { return value > 0 && !/^[+\u2212-]/.test(text) ? `+${text}` : text } /** The position the way the desk says it, with its sign: `+5mm`, `−2.5mm`, or `+120` contracts. Zero is flat and carries no sign. */ export function formatPosition(row: PositionRow): string { const v = row.position if (!Number.isFinite(v)) return NULL_TOKEN const sign = v > 0 ? "+" : "" if (row.quantityUnit === "contracts") return sign + formatQuantity(v) return sign + formatNotional(v, { unit: "mm" }) } /** Long, short, or flat, as a word for the row and the `data-side` a stylesheet reads. */ export function positionSide(position: number): "long" | "short" | "flat" { return position > 0 ? "long" : position < 0 ? "short" : "flat" } /** Book, instrument, position, average, mark, day P&L, total P&L, risk. Spread them into your own list to add, drop, or reorder. */ export function positionsColumns<T extends PositionRow>(options: PositionsColumnOptions<T> = {}): ColumnDef<T>[] { const price = options.price ?? twoDecimals const pnl = options.pnl ?? wholeSigned const risk = options.risk ?? wholeSigned const px = (value: unknown, row: T) => (typeof value === "number" ? price(value, row) : NULL_TOKEN) // The sign is printed and the side is named, so the color is not the only thing saying which way. const signed = (format: (value: number, row: T) => string) => (value: unknown, row: T) => (typeof value === "number" ? withSign(value, format(value, row)) : NULL_TOKEN) const colored = (format: (value: number, row: T) => string) => ({ value, row }: { value: unknown; row: T }) => <span className={directionClass(typeof value === "number" ? directionOf(0, value) : "flat")}>{signed(format)(value, row)}</span> return [ { key: "book", header: "Book", width: 84, sortable: true, flash: false, accessor: (r) => r.book ?? null }, { key: "instrument", header: "Instrument", width: 140, frozen: "left", sortable: true, flash: false, accessor: (r) => r.instrument, cell: ({ row }) => <span className="font-semibold">{row.instrument}</span> }, { key: "position", header: "Position", width: 96, numeric: true, sortable: true, accessor: (r) => r.position, format: (_, row) => formatPosition(row), cell: ({ row }) => ( <span data-side={positionSide(row.position)} className={directionClass(directionOf(0, row.position))}> {formatPosition(row)} </span> ), }, { key: "average", header: "Average", width: 96, numeric: true, sortable: true, flash: false, accessor: (r) => r.average ?? null, format: px }, { key: "mark", header: "Mark", width: 96, numeric: true, sortable: true, accessor: (r) => r.mark ?? null, format: px }, { key: "dayPnl", header: "Day P&L", width: 96, numeric: true, sortable: true, accessor: (r) => r.dayPnl ?? null, format: signed(pnl), cell: colored(pnl) }, { key: "totalPnl", header: "Total P&L", width: 104, numeric: true, sortable: true, accessor: (r) => r.totalPnl ?? null, format: signed(pnl), cell: colored(pnl) }, { key: "risk", header: options.riskHeader ?? "Risk", width: 88, numeric: true, sortable: true, accessor: (r) => r.risk ?? null, format: signed(risk), cell: colored(risk) }, ] } /** Totals of the day's P&L, the total P&L, and the risk, for the grid's footer; a book's position has no total across instruments. */ export function positionsTotals<T extends PositionRow>(options: PositionsColumnOptions<T> = {}): Record<string, (rows: T[]) => string> { const pnl = options.pnl ?? wholeSigned const risk = options.risk ?? wholeSigned const sum = (rows: T[], read: (row: T) => number | null | undefined, format: (value: number, row: T) => string) => { let total = 0 let any = false for (const row of rows) { const v = read(row) if (typeof v === "number" && Number.isFinite(v)) { total += v any = true } } return any && rows[0] ? withSign(total, format(total, rows[0])) : NULL_TOKEN } return { instrument: (rows) => `${rows.length} ${rows.length === 1 ? "position" : "positions"}`, dayPnl: (rows) => sum(rows, (r) => r.dayPnl, pnl), totalPnl: (rows) => sum(rows, (r) => r.totalPnl, pnl), risk: (rows) => sum(rows, (r) => r.risk, risk), } } export interface PositionsProps<T extends PositionRow = PositionRow> extends Omit<DataGridProps<T>, "columns" | "preset" | "label" | "footer" | "renderContextMenu">, PositionsColumnOptions<T> { /** `positionsColumns(options)` by default. */ columns?: ColumnDef<T>[] label?: string /** The totals row. `positionsTotals(options)` by default; `false` for none; your own record for other sums. */ totals?: false | Record<string, (rows: T[]) => string> /** Your items for the right-click menu. */ renderContextMenu?: (rows: T[], ids: RowId[]) => ReactNode } export function Positions<T extends PositionRow = PositionRow>({ columns, price, pnl, risk, riskHeader, label = "Positions", totals, renderContextMenu, className, store, getRowProps, selectionMode = "single", ...grid }: PositionsProps<T>) { // The grid's rows are memoized, so what it is handed keeps its identity from one render to the next; your callbacks are read through a ref. const latest = useRef({ renderContextMenu, getRowProps }) useEffect(() => { latest.current = { renderContextMenu, getRowProps } }) const options = useMemo<PositionsColumnOptions<T>>(() => ({ price, pnl, risk, riskHeader }), [price, pnl, risk, riskHeader]) const all = useMemo(() => columns ?? positionsColumns<T>(options), [columns, options]) const footer = useMemo(() => (totals === false ? undefined : (totals ?? positionsTotals<T>(options))), [totals, options]) const hasOwnMenu = Boolean(renderContextMenu) const menu = useCallback((rows: T[], ids: RowId[]) => latest.current.renderContextMenu?.(rows, ids), []) // The row says its side in words a screen reader hears, under whatever your own props say. const rowProps = useCallback((row: T, id: RowId) => { const own = latest.current.getRowProps?.(row, id) const side = positionSide(row.position) return { ...own, "data-state": own?.["data-state"] ?? side, "aria-description": own?.["aria-description"] ?? (side === "flat" ? undefined : side) } }, []) return ( <div data-slot="tradecn-positions" className={cn("flex h-full min-h-0 flex-col gap-1 lining-nums tabular-nums", className)}> <div className="min-h-0 flex-1"> <DataGrid<T> {...grid} store={store} preset="blotter" selectionMode={selectionMode} label={label} columns={all} footer={footer} getRowProps={rowProps} renderContextMenu={hasOwnMenu ? menu : undefined} /> </div> </div> ) }components/ui/ data-grid.tsx import { useVirtualizer } from "@tanstack/react-virtual" import { cn } from "cn" import { memo, useCallback, useEffect, useId, useLayoutEffect, useMemo, useRef, useState, useSyncExternalStore, type CSSProperties, type KeyboardEvent, type MouseEvent, type PointerEvent, type ReactNode, type UIEvent, } from "react" import { Checkbox } from "@/components/ui/checkbox" import { ContextMenu, ContextMenuContent, ContextMenuTrigger } from "@/components/ui/context-menu" import { DropdownMenu, DropdownMenuContent, DropdownMenuItem, DropdownMenuSeparator, DropdownMenuTrigger } from "@/components/ui/dropdown-menu" import { createFlashMemory, playFlash, useFlash, type FlashMemory } from "@/hooks/use-flash" import { useRow, useRowIds, useStoreMeta, useView } from "@/hooks/use-row-store" import { MONO_NUMERIC_CLASS, NULL_TOKEN, NUMERIC_CLASS } from "@/lib/format" import { applyRules, compareDirected, compareValues, compileComparator, compileFilter, type AppliedRules, type GridRules, type RuleDecoration } from "@/lib/grid-rules" import type { RowId, RowStore, RowView } from "@/lib/row-store" // A virtualized grid fed by a RowStore one row at a time. // // Rows subscribe to their own store entry, so a delta to one row re-renders one row; header, body, // and every other row stay put. Numeric cells flash by direction through a shared flash memory keyed // by row and column, so a row that scrolls out and back resumes its flash. Rows are positioned by // TanStack Virtual with a fixed height, which makes "keep the viewport pinned while rows arrive // above" exact arithmetic instead of measurement. // // Markup is a div grid with ARIA grid roles rather than a <table>: transform-positioned rows and // per-cell sticky frozen columns do not survive <tbody>. export interface ColumnDef<T> { key: string header: ReactNode width: number minWidth?: number align?: "left" | "right" | "center" frozen?: "left" sortable?: boolean hidden?: boolean /** The value the column shows; also what sorting and flash direction compare. */ accessor: (row: T) => unknown /** Text for the value. Defaults to String(value), NULL_TOKEN for null. */ format?: (value: unknown, row: T) => string /** Custom cell content. The cell still flashes by `accessor` value. `edit` is there when the column is editable and the grid has `onEdit`. */ cell?: (ctx: { row: T; value: unknown; rowId: RowId; edit?: CellEditHandle }) => ReactNode /** Flash on change. Defaults to the preset's variant for numeric columns and off otherwise. */ flash?: false | "fill" | "ring" /** Right-aligned, lining tabular figures in the numeric family, flashes by default. */ numeric?: boolean /** The family a numeric cell sets in: `numeric` (the sans, digits at one width) by default, or `mono` for a column of fraction quotes whose ticks must line up. */ font?: "numeric" | "mono" /** Reads a value typed into a rule in this column's own format (`99-16+` on a 32nds column). Default: a number for a numeric column, the text itself otherwise. */ parse?: (text: string) => unknown /** Lets the cell be edited in place, when the grid has `onEdit`. An edit is a command the server answers, never a local truth. */ edit?: CellEdit<T> } export interface ColumnState { order: string[] widths: Record<string, number> hidden: string[] } /** What stops an edit, in a sentence: what `parse` or `validate` return instead of a value. */ export interface EditProblem { problem: string } export function editProblem(problem: string): EditProblem { return { problem } } export function isEditProblem(value: unknown): value is EditProblem { return typeof value === "object" && value !== null && Object.keys(value).length === 1 && typeof (value as EditProblem).problem === "string" } /** How a column's cells are edited. Every function gets the row, because a step or a check can depend on it. */ export interface CellEdit<T> { /** Reads the typed text as a value, or says what is wrong with it. */ parse: (text: string, row: T) => unknown /** The text the editor opens with. Default: the column's `format`, else the value as text, blank for null. */ format?: (value: unknown, row: T) => string /** A check on the parsed value before it is committed. */ validate?: (value: unknown, row: T) => EditProblem | null | undefined /** Up and Down in the editor: the value one step away, ten with Shift. Left out, the arrows do nothing. */ step?: (value: unknown, dir: 1 | -1, big: boolean, row: T) => unknown /** Enter or Space on the focused cell commits this in place of opening an editor: a checkbox column. */ toggle?: (value: unknown, row: T) => unknown /** False keeps this row's cell read-only. Default: editable. */ canEdit?: (row: T) => boolean } /** What `onEdit` is handed: one cell's committed value, with what it replaces. */ export interface EditChange<T> { rowId: RowId key: string value: unknown previous: unknown row: T } /** * Where an edit stands. `editing` while the editor is open; `pending` from the commit until a later batch * brings the row's value to the committed one or `onEdit`'s promise resolves; `rejected` when that promise * rejects, with the server's message and the value that stands. */ export type EditStatus = | { kind: "editing"; text: string; problem: string | null; selectAll: boolean } | { kind: "pending"; value: unknown; text: string } | { kind: "rejected"; value: unknown; message: string } /** What a `cell` renderer gets for an editable column: the edit's status, and a way to commit a value of its own (a checkbox's). */ export interface CellEditHandle { status: EditStatus | undefined commit: (value: unknown) => void open: () => void } export type SortState = { key: string; dir: "asc" | "desc" } | null export type SelectionMode = "none" | "single" | "multi" export type DataGridPreset = "blotter" | "watchlist" | "rfq" | "option-chain" | "tape" | "parameters" export interface RowEnterBehavior { /** Highlight rows as they arrive. */ highlight: boolean /** Keep the first visible row where it is when rows arrive above it. */ pinViewport: boolean /** * Follow the tail: the viewport goes to the end as rows arrive there, until a key, a pointer, or a * scroll away from the end stops it. A "N new" pill then counts the arrivals and returns to the end. * What the `tape` preset does; off elsewhere. */ followTail?: boolean } export interface DataGridPresetConfig { rowHeight: number fontClass: string reorderHoldMs: number flash: "fill" | "ring" selectionMode: SelectionMode rowEnter: RowEnterBehavior announceRowCount: "off" | "debounced" } export const DATA_GRID_PRESETS: Record<DataGridPreset, DataGridPresetConfig> = { blotter: { rowHeight: 24, fontClass: "text-xs", reorderHoldMs: 750, flash: "fill", selectionMode: "multi", rowEnter: { highlight: true, pinViewport: true }, announceRowCount: "debounced" }, watchlist: { rowHeight: 22, fontClass: "text-xs", reorderHoldMs: 0, flash: "fill", selectionMode: "single", rowEnter: { highlight: false, pinViewport: false }, announceRowCount: "off" }, rfq: { rowHeight: 26, fontClass: "text-xs", reorderHoldMs: 1000, flash: "ring", selectionMode: "single", rowEnter: { highlight: true, pinViewport: true }, announceRowCount: "debounced" }, "option-chain": { rowHeight: 20, fontClass: "text-xs", reorderHoldMs: 0, flash: "ring", selectionMode: "none", rowEnter: { highlight: false, pinViewport: false }, announceRowCount: "off" }, tape: { rowHeight: 22, fontClass: "text-xs", reorderHoldMs: 0, flash: "fill", selectionMode: "single", rowEnter: { highlight: true, pinViewport: false, followTail: true }, announceRowCount: "debounced" }, parameters: { rowHeight: 24, fontClass: "text-xs", reorderHoldMs: 0, flash: "ring", selectionMode: "single", rowEnter: { highlight: false, pinViewport: true }, announceRowCount: "off" }, } export const EMPTY_COLUMN_STATE: ColumnState = { order: [], widths: {}, hidden: [] } export interface DataGridProps<T> { store: RowStore<T> /** A view you own (your comparator, your filter). Without it the grid makes one from `sort` and `filter`. */ view?: RowView<T> columns: ColumnDef<T>[] preset?: DataGridPreset rowHeight?: number overscan?: number /** Only used by the grid's own view. */ filter?: (row: T) => boolean reorderHoldMs?: number columnState?: ColumnState onColumnStateChange?: (state: ColumnState) => void sort?: SortState onSortChange?: (sort: SortState) => void selection?: ReadonlySet<RowId> onSelectionChange?: (selection: ReadonlySet<RowId>) => void selectionMode?: SelectionMode /** Show a checkbox column (multi only). */ selectionColumn?: boolean focusedRowId?: RowId | null onFocusedRowChange?: (id: RowId | null) => void onRowActivate?: (row: T, id: RowId) => void /** Items for the right-click menu, given the rows it applies to (the selection, or the row under the pointer). */ renderContextMenu?: (rows: T[], ids: RowId[]) => ReactNode rowEnter?: Partial<RowEnterBehavior> announceRowCount?: "off" | "debounced" /** Accessible name for the grid. */ label: string emptyState?: ReactNode getRowProps?: (row: T, id: RowId) => RowDecoration | undefined /** * Rules as data: cells and rows to color, rows to show, and the order, from `grid-rules`. The grid * wires them itself; `cell`, `getRowProps`, `filter`, and `sort` stay yours for what code has to do. * With a `view` of your own the grid ignores `rules.filter` and `rules.sort`, as it ignores `filter`. * Keep the object's identity stable between renders, as with `filter`. */ rules?: GridRules /** * Totals: a sticky row under the body with one value per column named here, given the view's rows * (filtered and ordered, what is on screen). Recomputed once per applied batch, never per frame, and * never flashed. Keep the object's identity stable between renders, as with `filter`. */ footer?: Record<string, (rows: T[]) => string> /** * A cell was edited: send the change on. Editing is on only when this is given, for the columns with * `edit`. The cell shows the committed value as pending until a later batch brings the row's value to it * or the promise you return resolves; a rejected promise keeps the previous value and prints the * message in the cell. Multi-cell paste is not part of this. */ onEdit?: (change: EditChange<T>) => void | Promise<unknown> flashWindowMs?: number className?: string /** Viewport size before layout is measured (tests, server rendering). */ initialRect?: { width: number; height: number } } /** What `getRowProps` may put on a row. A rule's decoration from `grid-rules` is one. */ export interface RowDecoration { className?: string "data-state"?: string "data-rule"?: string "data-tone"?: string "aria-description"?: string } type Resolved<T> = ColumnDef<T> & { width: number; minWidth: number } const EMPTY_SET: ReadonlySet<RowId> = new Set() const SELECT_WIDTH = 32 const ENTER_WINDOW_MS = 1500 function useControllable<V>(value: V | undefined, onChange: ((v: V) => void) | undefined, initial: V): [V, (v: V) => void] { const [internal, setInternal] = useState(initial) const controlled = value !== undefined const current = controlled ? value : internal const set = useCallback( (v: V) => { if (!controlled) setInternal(v) onChange?.(v) }, [controlled, onChange], ) return [current, set] } /** Nulls last, numbers numerically, everything else as text. `compareValues` in `grid-rules`, kept here by name. */ export function compareForSort(a: unknown, b: unknown): number { return compareValues(a, b) } /** The header's sort as a comparator, a null last whichever way it runs. */ export function comparatorFor<T>(columns: ColumnDef<T>[], sort: SortState): ((a: T, b: T) => number) | undefined { if (!sort) return undefined const col = columns.find((c) => c.key === sort.key) if (!col) return undefined return (x, y) => compareDirected(col.accessor(x), col.accessor(y), sort.dir) } /** One comparator after another: the first that tells two rows apart decides. Undefined when there is none. */ function chainComparators<T>(...comparators: (((a: T, b: T) => number) | undefined)[]): ((a: T, b: T) => number) | undefined { const list = comparators.filter((c): c is (a: T, b: T) => number => c !== undefined) if (!list.length) return undefined if (list.length === 1) return list[0] return (a, b) => { for (const compare of list) { const c = compare(a, b) if (c !== 0) return c } return 0 } } /** Order, hide, and size columns by state; frozen columns lead. */ export function resolveColumns<T>(columns: ColumnDef<T>[], state: ColumnState): Resolved<T>[] { const rank = new Map(state.order.map((k, i) => [k, i])) const hidden = new Set(state.hidden) const ordered = columns .map((c, i) => ({ c, r: rank.get(c.key) ?? 1e6 + i })) .sort((a, b) => a.r - b.r) .map(({ c }) => c) .filter((c) => !c.hidden && !hidden.has(c.key)) const frozen = ordered.filter((c) => c.frozen === "left") const rest = ordered.filter((c) => c.frozen !== "left") return [...frozen, ...rest].map((c) => { const minWidth = c.minWidth ?? 48 return { ...c, minWidth, width: Math.max(minWidth, state.widths[c.key] ?? c.width) } }) } /** CSV of the given rows and visible columns, RFC 4180 quoting. */ export function exportCsv<T>(store: RowStore<T>, columns: ColumnDef<T>[], ids: readonly RowId[]): string { const cols = columns.filter((c) => !c.hidden) const esc = (s: string) => (/[",\r\n]/.test(s) ? `"${s.replace(/"/g, '""')}"` : s) const header = cols.map((c) => esc(typeof c.header === "string" ? c.header : c.key)).join(",") const lines: string[] = [] for (const id of ids) { const row = store.getRow(id) if (row === undefined) continue lines.push( cols .map((c) => { const v = c.accessor(row) return esc(c.format ? c.format(v, row) : v === null || v === undefined ? "" : String(v)) }) .join(","), ) } return [header, ...lines].join("\r\n") + "\r\n" } // Editing. One editor at a time, its status kept in a tracker the cells subscribe to one key at a time, // so opening, typing in, or settling one cell re-renders that cell and nothing else. The controller is // one object for the grid's life; its callbacks read the latest props through a ref. const cellKey = (rowId: RowId, key: string) => `${rowId}\u0000${key}` interface EditTracker { get(key: string): EditStatus | undefined set(key: string, status: EditStatus | undefined): void subscribe(key: string, cb: () => void): () => void /** The cell whose editor is open. */ editing(): string | null } function createEditTracker(): EditTracker { const statuses = new Map<string, EditStatus>() const listeners = new Map<string, Set<() => void>>() let open: string | null = null return { get: (key) => statuses.get(key), set(key, status) { if (status) statuses.set(key, status) else statuses.delete(key) if (status?.kind === "editing") open = key else if (open === key) open = null const set = listeners.get(key) if (set) for (const cb of set) cb() }, subscribe(key, cb) { let set = listeners.get(key) if (!set) listeners.set(key, (set = new Set())) set.add(cb) return () => { set!.delete(cb) if (!set!.size) listeners.delete(key) } }, editing: () => open, } } interface EditController { tracker: EditTracker open(rowId: RowId, key: string, typed?: string): void type(rowId: RowId, key: string, text: string): void /** Parse, check, and send. `move` opens the next (1) or previous (-1) editable cell of the row after. */ commit(rowId: RowId, key: string, move?: 1 | -1): void /** A value a cell renderer settled itself (a checkbox): sent as it is. */ commitValue(rowId: RowId, key: string, value: unknown): void cancel(rowId: RowId, key: string): void step(rowId: RowId, key: string, dir: 1 | -1, big: boolean): void /** Focus left the editor: commit what parses, drop what does not. */ blur(rowId: RowId, key: string): void /** A later batch brought the row's value to the committed one. */ settle(rowId: RowId, key: string): void } function editText<T>(col: ColumnDef<T>, value: unknown, row: T): string { if (col.edit?.format) return col.edit.format(value, row) if (value === null || value === undefined) return "" return col.format ? col.format(value, row) : String(value) } function messageOf(error: unknown): string { if (error instanceof Error) return error.message if (typeof error === "string") return error return "Rejected" } function canEditCell<T>(col: ColumnDef<T> | undefined, row: T | undefined): col is ColumnDef<T> & { edit: CellEdit<T> } { return Boolean(col?.edit) && row !== undefined && (col!.edit!.canEdit?.(row) ?? true) } const noopSubscribe = () => () => {} const undefinedStatus = () => undefined const FILL_CLASSES = "data-[direction=up]:bg-up-soft data-[direction=down]:bg-down-soft data-[direction=flat]:bg-flat-soft" const RING_CLASSES = "data-[direction=up]:shadow-[inset_0_0_0_1px_var(--up)] data-[direction=down]:shadow-[inset_0_0_0_1px_var(--down)] data-[direction=flat]:shadow-[inset_0_0_0_1px_var(--flat)]" function alignClass(col: { align?: "left" | "right" | "center"; numeric?: boolean }) { const a = col.align ?? (col.numeric ? "right" : "left") return a === "right" ? "text-right" : a === "center" ? "text-center" : "text-left" } interface CellProps<T> { col: Resolved<T> row: T rowId: RowId colIndex: number left: number | undefined memory: FlashMemory flashVariant: "fill" | "ring" flashWindowMs: number focusedCol: boolean rules: AppliedRules<T> | null /** The row's own rule, for a frozen cell to paint: its opaque background would otherwise cut a gap in the row's tint. */ rowRule: RuleDecoration | undefined /** The grid's editing, or null when it has no `onEdit`. */ edits: EditController | null } interface CellEditorProps { rowId: RowId colKey: string label: string status: Extract<EditStatus, { kind: "editing" }> numeric: boolean className: string edits: EditController } // The editor: a bare input the size of the cell. Enter commits, Escape reverts, Tab and Shift+Tab commit // and move along the row, bare Up and Down step. With a modifier held the arrows are not its business: // they belong to whoever listens above it, the way a ticket's mod+up reaches its registry from a field. function CellEditor({ rowId, colKey, label, status, numeric, className, edits }: CellEditorProps) { const ref = useRef<HTMLInputElement>(null) const selectAll = status.selectAll useEffect(() => { const el = ref.current if (!el) return el.focus({ preventScroll: true }) if (selectAll) el.select() else el.setSelectionRange(el.value.length, el.value.length) // On mount only: a keystroke must not reselect the text under the hand. // eslint-disable-next-line react-hooks/exhaustive-deps }, []) const onKeyDown = (e: KeyboardEvent<HTMLInputElement>) => { const mod = e.metaKey || e.ctrlKey || e.altKey switch (e.key) { case "Enter": e.preventDefault() edits.commit(rowId, colKey) return case "Escape": e.preventDefault() edits.cancel(rowId, colKey) return case "Tab": e.preventDefault() edits.commit(rowId, colKey, e.shiftKey ? -1 : 1) return case "ArrowUp": case "ArrowDown": if (mod) return e.preventDefault() edits.step(rowId, colKey, e.key === "ArrowUp" ? 1 : -1, e.shiftKey) return } } return ( <input ref={ref} data-cell-editor="" data-numeric={numeric ? "" : undefined} aria-label={label} aria-invalid={status.problem ? true : undefined} aria-description={status.problem ?? undefined} title={status.problem ?? undefined} value={status.text} autoComplete="off" spellCheck={false} inputMode={numeric ? "decimal" : undefined} className={cn("h-full w-full min-w-0 bg-background px-2 text-inherit outline-none ring-1 ring-inset ring-ring aria-invalid:ring-destructive", numeric && "text-right", className)} onChange={(e) => edits.type(rowId, colKey, e.target.value)} onKeyDown={onKeyDown} onBlur={() => edits.blur(rowId, colKey)} /> ) } function Cell<T>({ col, row, rowId, colIndex, left, memory, flashVariant, flashWindowMs, focusedCol, rules, rowRule, edits }: CellProps<T>) { const value = col.accessor(row) const ref = useRef<HTMLDivElement>(null) const flash = col.flash ?? (col.numeric ? flashVariant : false) const key = cellKey(rowId, col.key) useFlash(ref, value, { memory, cellKey: key, variant: flash || "fill", windowMs: flashWindowMs, disabled: !flash }) // Editable cells follow their own entry in the tracker; the rest subscribe to nothing. const editable = edits !== null && Boolean(col.edit) const tracker = editable ? edits.tracker : null const subscribe = useCallback((cb: () => void) => (tracker ? tracker.subscribe(key, cb) : noopSubscribe()), [tracker, key]) const get = useCallback(() => (tracker ? tracker.get(key) : undefined), [tracker, key]) const status = useSyncExternalStore(subscribe, get, undefinedStatus) // A later batch brought the row's value to the committed one: the edit is settled, and the cell reads the store again. const settled = status?.kind === "pending" && Object.is(status.value, value) useEffect(() => { if (settled) edits?.settle(rowId, col.key) }, [settled, edits, rowId, col.key]) const handle = useMemo<CellEditHandle | undefined>( () => (editable ? { status, commit: (next) => edits!.commitValue(rowId, col.key, next), open: () => edits!.open(rowId, col.key) } : undefined), [editable, status, edits, rowId, col.key], ) const numericClass = col.numeric ? (col.font === "mono" ? MONO_NUMERIC_CLASS : NUMERIC_CLASS) : "" const header = typeof col.header === "string" ? col.header : col.key const editing = status?.kind === "editing" const pendingText = status?.kind === "pending" && !col.cell ? status.text : null const content = editing ? null : pendingText !== null ? pendingText : col.cell ? col.cell({ row, value, rowId, edit: handle }) : col.format ? col.format(value, row) : value === null || value === undefined ? NULL_TOKEN : String(value) // A matched rule names itself on the cell and says its words to a screen reader; the color is the hint. const rule = rules?.cell(col.key, row) const rejected = status?.kind === "rejected" ? status.message : null return ( <div ref={ref} role="gridcell" aria-colindex={colIndex + 1} aria-description={rejected ?? rule?.["aria-description"]} aria-readonly={editable ? !canEditCell(col, row) : undefined} data-col={col.key} data-numeric={col.numeric ? "" : undefined} data-focused-col={focusedCol || undefined} data-rule={rule?.["data-rule"]} data-tone={rule?.["data-tone"]} data-editable={editable && canEditCell(col, row) ? "" : undefined} data-editing={editing || undefined} data-pending={status?.kind === "pending" || undefined} data-rejected={rejected ?? undefined} title={rejected ?? (typeof content === "string" ? content : undefined)} className={cn( "flex h-full min-w-0 items-center truncate", !editing && "px-2", alignClass(col), col.numeric && cn("justify-end", numericClass), col.align === "center" && "justify-center", flash === "ring" ? RING_CLASSES : flash === "fill" ? FILL_CLASSES : undefined, left !== undefined && "sticky z-10 bg-background", focusedCol && "bg-muted/50", status?.kind === "pending" && "text-muted-foreground italic", rejected !== null && "text-destructive", rule?.className ?? (left !== undefined ? rowRule?.className : undefined), )} style={left !== undefined ? { left } : undefined} > {editing ? ( <CellEditor rowId={rowId} colKey={col.key} label={header} status={status} numeric={Boolean(col.numeric)} className={numericClass} edits={edits!} /> ) : ( // Beside a refusal the value keeps its digits and the message is what gives way. <span className={cn("truncate", rejected !== null && "shrink-0")}>{content}</span> )} {rejected !== null && <span data-edit-message="" className="ml-1 truncate">{rejected}</span>} </div> ) } interface RowProps<T> { store: RowStore<T> id: RowId index: number domId: string columns: Resolved<T>[] template: string lefts: (number | undefined)[] width: number height: number start: number selected: boolean focused: boolean focusedColKey: string | null selectionColumn: boolean onToggle: (id: RowId) => void memory: FlashMemory flashVariant: "fill" | "ring" flashWindowMs: number entered: Set<RowId> highlightEnter: boolean getRowProps?: (row: T, id: RowId) => RowDecoration | undefined rules: AppliedRules<T> | null edits: EditController | null } function RowInner<T>(p: RowProps<T>) { const row = useRow(p.store, p.id) const ref = useRef<HTMLDivElement>(null) useLayoutEffect(() => { if (p.highlightEnter && p.entered.has(p.id) && ref.current) { p.entered.delete(p.id) playFlash(ref.current, "flat", { windowMs: ENTER_WINDOW_MS, variant: "fill" }) } // eslint-disable-next-line react-hooks/exhaustive-deps }, []) if (row === undefined) return null const extra = p.getRowProps?.(row, p.id) // A row rule paints under whatever your own props say: yours are read last, so they win a class. const rule = p.rules?.getRowProps(row) return ( <div ref={ref} role="row" id={p.domId} data-row-id={p.id} data-state={extra?.["data-state"]} data-rule={extra?.["data-rule"] ?? rule?.["data-rule"]} data-tone={extra?.["data-tone"] ?? rule?.["data-tone"]} aria-description={extra?.["aria-description"] ?? rule?.["aria-description"]} data-focused={p.focused || undefined} aria-rowindex={p.index + 2} aria-selected={p.selected || undefined} className={cn( "absolute top-0 left-0 grid items-stretch border-b border-border/60", FILL_CLASSES, p.selected && "bg-accent", p.focused && "outline-1 -outline-offset-1 outline-ring", rule?.className, extra?.className, )} style={{ gridTemplateColumns: p.template, width: p.width, height: p.height, transform: `translateY(${p.start}px)` }} > {p.selectionColumn && ( <div role="gridcell" aria-colindex={1} className="sticky left-0 z-10 flex items-center justify-center bg-background"> <Checkbox checked={p.selected} onCheckedChange={() => p.onToggle(p.id)} aria-label="Select row" /> </div> )} {p.columns.map((col, i) => ( <Cell key={col.key} col={col} row={row} rowId={p.id} colIndex={i + (p.selectionColumn ? 1 : 0)} left={p.lefts[i]} memory={p.memory} flashVariant={p.flashVariant} flashWindowMs={p.flashWindowMs} focusedCol={p.focusedColKey === col.key} rules={p.rules} rowRule={rule} edits={p.edits} /> ))} </div> ) } const Row = memo(RowInner) as typeof RowInner interface FooterProps<T> { store: RowStore<T> ids: readonly RowId[] columns: Resolved<T>[] template: string lefts: (number | undefined)[] width: number height: number footer: Record<string, (rows: T[]) => string> selectionColumn: boolean rowIndex: number } // The totals row. Its own component on the store's meta, which changes once per applied batch: the // view's rows are read once and each column's function runs once, at the feed's pace and never per // frame or per row. Nothing here flashes. function FooterInner<T>(p: FooterProps<T>) { const meta = useStoreMeta(p.store) const values = useMemo(() => { void meta.version const rows: T[] = [] for (const id of p.ids) { const row = p.store.getRow(id) if (row !== undefined) rows.push(row) } const out = new Map<string, string>() for (const col of p.columns) { const total = p.footer[col.key] if (total) out.set(col.key, total(rows)) } return out }, [meta.version, p.ids, p.columns, p.footer, p.store]) return ( <div role="row" aria-rowindex={p.rowIndex} data-grid-footer="" className="sticky bottom-0 z-20 mt-auto grid border-t border-border bg-background font-medium" style={{ gridTemplateColumns: p.template, width: p.width, height: p.height }}> {p.selectionColumn && <div role="gridcell" aria-colindex={1} className="sticky left-0 z-10 bg-background" />} {p.columns.map((col, i) => { const left = p.lefts[i] const text = values.get(col.key) return ( <div key={col.key} role="gridcell" aria-colindex={i + (p.selectionColumn ? 1 : 0) + 1} data-col={col.key} data-numeric={col.numeric ? "" : undefined} title={text} className={cn("flex h-full min-w-0 items-center truncate px-2", alignClass(col), col.numeric && cn("justify-end", col.font === "mono" ? MONO_NUMERIC_CLASS : NUMERIC_CLASS), col.align === "center" && "justify-center", left !== undefined && "sticky z-10 bg-background")} style={left !== undefined ? { left } : undefined} > <span className="truncate">{text}</span> </div> ) })} </div> ) } const FooterRow = memo(FooterInner) as typeof FooterInner export function DataGrid<T>(props: DataGridProps<T>) { const { store, columns, label, className, emptyState, getRowProps, onRowActivate, renderContextMenu, footer, onEdit, initialRect, overscan = 8, } = props const preset = DATA_GRID_PRESETS[props.preset ?? "blotter"] const rowHeight = props.rowHeight ?? preset.rowHeight const selectionMode = props.selectionMode ?? preset.selectionMode const selectionColumn = Boolean(props.selectionColumn) && selectionMode === "multi" const rowEnter = { ...preset.rowEnter, ...props.rowEnter } const announceRowCount = props.announceRowCount ?? preset.announceRowCount const flashWindowMs = props.flashWindowMs ?? 900 const reorderHoldMs = props.reorderHoldMs ?? preset.reorderHoldMs const [sort, setSort] = useControllable(props.sort, props.onSortChange, null as SortState) const [columnState, setColumnState] = useControllable(props.columnState, props.onColumnStateChange, EMPTY_COLUMN_STATE) const [selection, setSelection] = useControllable(props.selection, props.onSelectionChange, EMPTY_SET) const [focusedRowId, setFocusedRowId] = useControllable<RowId | null>(props.focusedRowId, props.onFocusedRowChange, null) const [focusedColKey, setFocusedColKey] = useState<string | null>(null) const anchorRef = useRef<RowId | null>(null) // The view: yours, or one made from sort, filter, and the rules. A header sort comes first and the // rules' order breaks its ties; every filter rule has to hold, along with your own filter. const ruleSort = props.rules?.sort const ruleFilter = props.rules?.filter const ruleColumns = props.rules?.columns const comparator = useMemo(() => chainComparators(comparatorFor(columns, sort), ruleSort?.length ? compileComparator(ruleSort, columns) : undefined), [columns, sort, ruleSort]) const ownFilter = props.filter const filter = useMemo(() => { const byRules = ruleFilter?.length ? compileFilter(ruleFilter, columns) : undefined if (!byRules) return ownFilter if (!ownFilter) return byRules return (row: T) => ownFilter(row) && byRules(row) }, [ownFilter, ruleFilter, columns]) const rules = useMemo(() => (ruleColumns?.length ? applyRules(ruleColumns, columns) : null), [ruleColumns, columns]) const ownOptions = useMemo(() => (props.view ? null : { comparator, filter, reorderHoldMs }), [props.view, comparator, filter, reorderHoldMs]) const ownView = useView(store, ownOptions) const view = props.view ?? ownView! const ids = useRowIds(view) const indexOf = useMemo(() => new Map(ids.map((id, i) => [id, i] as const)), [ids]) const resolved = useMemo(() => resolveColumns(columns, columnState), [columns, columnState]) const lefts = useMemo(() => { let x = selectionColumn ? SELECT_WIDTH : 0 return resolved.map((c) => { if (c.frozen !== "left") return undefined const left = x x += c.width return left }) }, [resolved, selectionColumn]) const template = useMemo(() => (selectionColumn ? `${SELECT_WIDTH}px ` : "") + resolved.map((c) => `${c.width}px`).join(" "), [resolved, selectionColumn]) const totalWidth = useMemo(() => resolved.reduce((s, c) => s + c.width, selectionColumn ? SELECT_WIDTH : 0), [resolved, selectionColumn]) const memory = useMemo(() => createFlashMemory(), []) const scrollRef = useRef<HTMLDivElement>(null) const rootRef = useRef<HTMLDivElement>(null) // Editing: one controller for the grid's life, reading the latest columns and onEdit through a ref, so the // memoized rows are handed one object and never re-render for it. Null without `onEdit`: nothing opens. const editLatest = useRef({ columns, resolved, onEdit }) useEffect(() => { editLatest.current = { columns, resolved, onEdit } }) const editable = Boolean(onEdit) const edits = useMemo<EditController | null>(() => { if (!editable) return null const tracker = createEditTracker() const column = (key: string) => editLatest.current.columns.find((c) => c.key === key) const focusGrid = () => rootRef.current?.focus({ preventScroll: true }) const send = (rowId: RowId, col: ColumnDef<T> & { edit: CellEdit<T> }, row: T, value: unknown) => { const previous = col.accessor(row) const k = cellKey(rowId, col.key) if (Object.is(value, previous)) { tracker.set(k, undefined) return } tracker.set(k, { kind: "pending", value, text: editText(col, value, row) }) let result: void | Promise<unknown> try { result = editLatest.current.onEdit?.({ rowId, key: col.key, value, previous, row }) } catch (error) { tracker.set(k, { kind: "rejected", value: previous, message: messageOf(error) }) return } if (result && typeof (result as Promise<unknown>).then === "function") { ;(result as Promise<unknown>).then( () => { const now = tracker.get(k) if (now?.kind === "pending" && Object.is(now.value, value)) tracker.set(k, undefined) }, (error: unknown) => { const now = tracker.get(k) if (now?.kind === "pending" && Object.is(now.value, value)) tracker.set(k, { kind: "rejected", value: previous, message: messageOf(error) }) }, ) } } const moveOn = (rowId: RowId, key: string, move: 1 | -1 | undefined) => { if (!move) return focusGrid() const row = store.getRow(rowId) const list = editLatest.current.resolved let i = list.findIndex((c) => c.key === key) + move for (; i >= 0 && i < list.length; i += move) { const next = list[i]! if (canEditCell(next, row) && !next.edit.toggle) { setFocusedColKey(next.key) return open(rowId, next.key) } } focusGrid() } function open(rowId: RowId, key: string, typed?: string) { const col = column(key) const row = store.getRow(rowId) if (!canEditCell(col, row) || col.edit.toggle) return const k = cellKey(rowId, key) const before = tracker.editing() if (before && before !== k) tracker.set(before, undefined) // A pending cell reopens on what it shows, the committed value, not on the value the store still holds. const now = tracker.get(k) const text = now?.kind === "pending" ? now.text : editText(col, col.accessor(row!), row!) tracker.set(k, { kind: "editing", text: typed ?? text, problem: null, selectAll: typed === undefined }) } const controller: EditController = { tracker, open, type(rowId, key, text) { const k = cellKey(rowId, key) const now = tracker.get(k) if (now?.kind === "editing") tracker.set(k, { ...now, text, problem: null }) }, commit(rowId, key, move) { const k = cellKey(rowId, key) const now = tracker.get(k) if (now?.kind !== "editing") return const col = column(key) const row = store.getRow(rowId) if (!canEditCell(col, row)) { tracker.set(k, undefined) return focusGrid() } const parsed = col.edit.parse(now.text, row!) const problem = isEditProblem(parsed) ? parsed : col.edit.validate?.(parsed, row!) if (problem) { tracker.set(k, { ...now, problem: problem.problem }) return } send(rowId, col, row!, parsed) moveOn(rowId, key, move) }, commitValue(rowId, key, value) { const col = column(key) const row = store.getRow(rowId) if (!canEditCell(col, row)) return const problem = col.edit.validate?.(value, row!) if (problem) { tracker.set(cellKey(rowId, key), { kind: "rejected", value: col.accessor(row!), message: problem.problem }) return } send(rowId, col, row!, value) }, cancel(rowId, key) { const k = cellKey(rowId, key) if (tracker.get(k)?.kind === "editing") tracker.set(k, undefined) focusGrid() }, step(rowId, key, dir, big) { const k = cellKey(rowId, key) const now = tracker.get(k) const col = column(key) const row = store.getRow(rowId) if (now?.kind !== "editing" || !canEditCell(col, row) || !col.edit.step) return const typed = col.edit.parse(now.text, row!) const from = isEditProblem(typed) ? col.accessor(row!) : typed const next = col.edit.step(from, dir, big, row!) tracker.set(k, { ...now, text: editText(col, next, row!), problem: null }) }, blur(rowId, key) { const k = cellKey(rowId, key) const now = tracker.get(k) if (now?.kind !== "editing") return const col = column(key) const row = store.getRow(rowId) if (!canEditCell(col, row)) return tracker.set(k, undefined) const parsed = col.edit.parse(now.text, row!) if (isEditProblem(parsed) || col.edit.validate?.(parsed, row!)) return tracker.set(k, undefined) send(rowId, col, row!, parsed) }, settle(rowId, key) { const k = cellKey(rowId, key) if (tracker.get(k)?.kind === "pending") tracker.set(k, undefined) }, } return controller }, [editable, store]) const virtualizer = useVirtualizer({ count: ids.length, getScrollElement: () => scrollRef.current, estimateSize: () => rowHeight, overscan, getItemKey: (i) => ids[i]!, initialRect, }) const items = virtualizer.getVirtualItems() const uid = useId() const domId = (id: RowId) => `${uid}-${id}` // A tape follows its tail: new rows land at the end and the viewport goes there after every commit, // until a key, a pointer, or a scroll away from the end stops it. Then the arrivals count up on a // pill, and pressing it, or scrolling back to the end, follows again. Both are state set from // handlers, so the effect below only reads them. const followTail = Boolean(rowEnter.followTail) const [following, setFollowing] = useState(true) const [anchor, setAnchor] = useState(0) const behind = followTail && !following ? Math.max(0, ids.length - anchor) : 0 useLayoutEffect(() => { if (followTail && scrollRef.current) scrollRef.current.scrollTop = scrollRef.current.scrollHeight }, [followTail]) // Rows arriving: highlight, pin the viewport or follow the tail, announce. Rows leaving: forget their flashes. const entered = useRef(new Set<RowId>()).current const prevIdsRef = useRef<readonly RowId[]>(ids) const newSinceAnnounce = useRef(0) useLayoutEffect(() => { const prev = prevIdsRef.current if (prev === ids) return const prevSet = new Set(prev) const nowSet = new Set(ids) const arrived: RowId[] = [] for (const id of ids) if (!prevSet.has(id)) arrived.push(id) let departed = 0 for (const id of prev) { if (!nowSet.has(id)) { departed++ memory.forget(`${id}\u0000`) } } if ((arrived.length || departed) && rowEnter.pinViewport && scrollRef.current) { const el = scrollRef.current const firstIndex = Math.floor(el.scrollTop / rowHeight) const firstId = prev[firstIndex] const nextIndex = firstId !== undefined ? indexOf.get(firstId) : undefined if (nextIndex !== undefined && nextIndex !== firstIndex) el.scrollTop += (nextIndex - firstIndex) * rowHeight } if (arrived.length && followTail && following && scrollRef.current) scrollRef.current.scrollTop = scrollRef.current.scrollHeight if (arrived.length && rowEnter.highlight) for (const id of arrived) entered.add(id) newSinceAnnounce.current += arrived.length prevIdsRef.current = ids }, [ids, indexOf, rowHeight, rowEnter.pinViewport, rowEnter.highlight, followTail, following, entered, memory]) const stopFollowing = () => { if (!followTail || !following) return setFollowing(false) setAnchor(ids.length) } const toTail = () => { const el = scrollRef.current if (el) el.scrollTop = el.scrollHeight setFollowing(true) } const onScroll = followTail ? (e: UIEvent<HTMLDivElement>) => { const el = e.currentTarget const atTail = el.scrollTop + el.clientHeight >= el.scrollHeight - 1 if (atTail === following) return if (atTail) setFollowing(true) else stopFollowing() } : undefined const [announcement, setAnnouncement] = useState("") useEffect(() => { if (announceRowCount === "off") return const t = setTimeout(() => { const fresh = newSinceAnnounce.current newSinceAnnounce.current = 0 setAnnouncement(`${ids.length.toLocaleString()} rows${fresh ? `, ${fresh.toLocaleString()} new` : ""}`) }, 1000) return () => clearTimeout(t) }, [ids.length, announceRowCount]) // Selection and focus, by id. const select = useCallback( (targets: RowId[], mode: "replace" | "toggle" | "range") => { if (selectionMode === "none") return if (selectionMode === "single" || mode === "replace") { setSelection(new Set(targets.slice(-1))) anchorRef.current = targets[targets.length - 1] ?? null return } const next = new Set(selection) if (mode === "toggle") { for (const id of targets) if (next.has(id)) next.delete(id) else next.add(id) anchorRef.current = targets[targets.length - 1] ?? anchorRef.current } else { const to = targets[targets.length - 1]! const from = anchorRef.current ?? to const a = indexOf.get(from) ?? 0 const b = indexOf.get(to) ?? 0 for (let i = Math.min(a, b); i <= Math.max(a, b); i++) next.add(ids[i]!) } setSelection(next) }, [ids, indexOf, selection, selectionMode, setSelection], ) const focusIndex = useCallback( (index: number, extend = false) => { if (!ids.length) return const i = Math.max(0, Math.min(ids.length - 1, index)) const id = ids[i]! setFocusedRowId(id) virtualizer.scrollToIndex(i, { align: "auto" }) if (extend && selectionMode === "multi") select([id], "range") else if (selectionMode === "single") select([id], "replace") }, [ids, select, selectionMode, setFocusedRowId, virtualizer], ) const cycleSort = useCallback( (key: string) => { const col = columns.find((c) => c.key === key) if (!col?.sortable) return setSort(!sort || sort.key !== key ? { key, dir: "asc" } : sort.dir === "asc" ? { key, dir: "desc" } : null) }, [columns, sort, setSort], ) const updateColumns = useCallback( (fn: (s: ColumnState) => ColumnState) => setColumnState(fn(columnState)), [columnState, setColumnState], ) const moveColumn = useCallback( (key: string, delta: -1 | 1) => { const order = resolved.map((c) => c.key) const i = order.indexOf(key) const j = i + delta if (i < 0 || j < 0 || j >= order.length) return ;[order[i], order[j]] = [order[j]!, order[i]!] updateColumns((s) => ({ ...s, order })) }, [resolved, updateColumns], ) const resizeColumn = useCallback( (key: string, width: number) => { const col = resolved.find((c) => c.key === key) if (!col) return updateColumns((s) => ({ ...s, widths: { ...s.widths, [key]: Math.max(col.minWidth, Math.round(width)) } })) }, [resolved, updateColumns], ) const hideColumn = useCallback((key: string) => updateColumns((s) => ({ ...s, hidden: [...new Set([...s.hidden, key])] })), [updateColumns]) const resetColumns = useCallback(() => setColumnState(EMPTY_COLUMN_STATE), [setColumnState]) const visibleCount = Math.max(1, Math.floor((scrollRef.current?.clientHeight ?? initialRect?.height ?? rowHeight * 10) / rowHeight)) // The focused cell's column when it can be edited now, else undefined. const editableFocus = () => { if (!edits || focusedRowId === null || focusedColKey === null) return undefined const col = resolved.find((c) => c.key === focusedColKey) return canEditCell(col, store.getRow(focusedRowId)) ? col : undefined } const onKeyDown = (e: KeyboardEvent<HTMLDivElement>) => { // The editor owns its keys; what it lets through (a modifier-held arrow) is for the listeners above the grid. if ((e.target as HTMLElement).closest?.("[data-cell-editor]")) return view.touch() stopFollowing() const fi = focusedRowId !== null ? (indexOf.get(focusedRowId) ?? -1) : -1 const ci = focusedColKey !== null ? resolved.findIndex((c) => c.key === focusedColKey) : -1 const mod = e.metaKey || e.ctrlKey // Typing on an editable cell opens its editor with the character typed. if (e.key.length === 1 && e.key !== " " && !mod && !e.altKey) { const col = editableFocus() if (col && !col.edit.toggle) { e.preventDefault() edits!.open(focusedRowId!, col.key, e.key) return } } switch (e.key) { case "ArrowDown": e.preventDefault() focusIndex(fi + 1, e.shiftKey) return case "ArrowUp": e.preventDefault() focusIndex(fi <= 0 ? 0 : fi - 1, e.shiftKey) return case "PageDown": e.preventDefault() focusIndex(fi + visibleCount, e.shiftKey) return case "PageUp": e.preventDefault() focusIndex(fi - visibleCount, e.shiftKey) return case "Home": e.preventDefault() focusIndex(0, e.shiftKey) return case "End": e.preventDefault() focusIndex(ids.length - 1, e.shiftKey) return case "ArrowLeft": case "ArrowRight": { e.preventDefault() const delta = e.key === "ArrowLeft" ? -1 : 1 if (e.altKey && focusedColKey) { if (e.shiftKey) resizeColumn(focusedColKey, (resolved[ci]?.width ?? 0) + delta * 8) else moveColumn(focusedColKey, delta) return } const next = resolved[Math.max(0, Math.min(resolved.length - 1, ci < 0 ? (delta > 0 ? 0 : resolved.length - 1) : ci + delta))] setFocusedColKey(next?.key ?? null) return } case " ": { e.preventDefault() const col = editableFocus() if (col?.edit.toggle) { const row = store.getRow(focusedRowId!)! edits!.commitValue(focusedRowId!, col.key, col.edit.toggle(col.accessor(row), row)) return } if (focusedRowId !== null) select([focusedRowId], selectionMode === "multi" ? "toggle" : "replace") return } case "Enter": case "F2": { const col = editableFocus() if (col) { e.preventDefault() const row = store.getRow(focusedRowId!)! if (col.edit.toggle) edits!.commitValue(focusedRowId!, col.key, col.edit.toggle(col.accessor(row), row)) else edits!.open(focusedRowId!, col.key) return } if (e.key === "F2") return if (focusedRowId !== null) { const row = store.getRow(focusedRowId) if (row !== undefined) onRowActivate?.(row, focusedRowId) } return } case "Escape": setSelection(EMPTY_SET) return case "a": case "A": if (mod && selectionMode === "multi") { e.preventDefault() setSelection(new Set(ids)) } return case "s": case "S": if (e.altKey && focusedColKey) { e.preventDefault() cycleSort(focusedColKey) } return case "h": case "H": if (e.altKey && focusedColKey) { e.preventDefault() hideColumn(focusedColKey) } return case "ContextMenu": case "F10": if (e.key === "F10" && !e.shiftKey) return e.preventDefault() openContextMenuAtFocus() return } } const openContextMenuAtFocus = () => { if (focusedRowId === null) return const el = scrollRef.current?.querySelector<HTMLElement>(`[data-row-id="${cssEscape(focusedRowId)}"]`) if (!el) return const r = el.getBoundingClientRect() el.dispatchEvent(new window.MouseEvent("contextmenu", { bubbles: true, cancelable: true, clientX: r.left + 8, clientY: r.top + r.height / 2, button: 2 })) } // Right-click targets the row under the pointer: focus it, and make it the selection unless it is already selected. const onContextMenuCapture = (e: MouseEvent<HTMLDivElement>) => { const rowEl = (e.target as HTMLElement).closest<HTMLElement>("[data-row-id]") const id = rowEl?.dataset.rowId if (!id) return setFocusedRowId(id) if (!selection.has(id)) select([id], "replace") } const onRowPointerDown = (e: PointerEvent<HTMLDivElement>) => { view.touch() stopFollowing() const rowEl = (e.target as HTMLElement).closest<HTMLElement>("[data-row-id]") const id = rowEl?.dataset.rowId if (!id) return if ((e.target as HTMLElement).closest('[data-slot="checkbox"]')) return setFocusedRowId(id) if (e.button !== 0) return if (e.shiftKey) select([id], "range") else if (e.metaKey || e.ctrlKey) select([id], "toggle") else select([id], "replace") } // A double click on an editable cell opens it; anywhere else on the row it activates the row. const onRowDoubleClick = (e: MouseEvent<HTMLDivElement>) => { const target = e.target as HTMLElement const id = target.closest<HTMLElement>("[data-row-id]")?.dataset.rowId const row = id !== undefined ? store.getRow(id) : undefined if (id === undefined || row === undefined) return const key = target.closest<HTMLElement>("[data-col]")?.dataset.col const col = key !== undefined ? resolved.find((c) => c.key === key) : undefined if (edits && canEditCell(col, row) && !col.edit.toggle) { setFocusedRowId(id) setFocusedColKey(col.key) edits.open(id, col.key) return } onRowActivate?.(row, id) } const toggle = useCallback((id: RowId) => select([id], "toggle"), [select]) const contextRows = useMemo(() => { const targets = selection.size ? [...selection] : focusedRowId !== null ? [focusedRowId] : [] return { ids: targets, rows: targets.map((id) => store.getRow(id)).filter((r): r is T => r !== undefined) } }, [selection, focusedRowId, store]) const body = ( <div ref={scrollRef} className="relative h-full min-h-0 flex-1 overflow-auto" onPointerDownCapture={onRowPointerDown} onDoubleClick={onRowDoubleClick} onContextMenuCapture={renderContextMenu ? onContextMenuCapture : undefined} onScroll={onScroll} > {/* At least the viewport tall, so a footer sits at the bottom edge when the rows do not reach it. */} <div className="flex min-h-full flex-col"> <div role="row" aria-rowindex={1} className="sticky top-0 z-20 grid border-b border-border bg-background text-muted-foreground" style={{ gridTemplateColumns: template, width: totalWidth, height: rowHeight }} > {selectionColumn && <div role="columnheader" aria-colindex={1} className="sticky left-0 z-30 bg-background" />} {resolved.map((col, i) => ( <HeaderCell key={col.key} col={col} colIndex={i + (selectionColumn ? 1 : 0)} left={lefts[i]} sort={sort?.key === col.key ? sort.dir : null} focused={focusedColKey === col.key} canMoveLeft={i > 0} canMoveRight={i < resolved.length - 1} onSort={() => cycleSort(col.key)} onFocus={() => setFocusedColKey(col.key)} onHide={() => hideColumn(col.key)} onMove={(d) => moveColumn(col.key, d)} onReset={resetColumns} onResize={(w) => resizeColumn(col.key, w)} hiddenCount={columnState.hidden.length} /> ))} </div> {ids.length === 0 ? ( <div className="p-4 text-muted-foreground">{emptyState ?? "No rows"}</div> ) : ( <div role="rowgroup" className="relative shrink-0" style={{ height: virtualizer.getTotalSize(), width: totalWidth }}> {items.map((v) => { const id = ids[v.index]! return ( <Row key={v.key} store={store} id={id} index={v.index} domId={domId(id)} columns={resolved} template={template} lefts={lefts} width={totalWidth} height={rowHeight} start={v.start} selected={selection.has(id)} focused={focusedRowId === id} focusedColKey={focusedColKey} selectionColumn={selectionColumn} onToggle={toggle} memory={memory} flashVariant={preset.flash} flashWindowMs={flashWindowMs} entered={entered} highlightEnter={rowEnter.highlight} getRowProps={getRowProps} rules={rules} edits={edits} /> ) })} </div> )} {footer && <FooterRow store={store} ids={ids} columns={resolved} template={template} lefts={lefts} width={totalWidth} height={rowHeight} footer={footer} selectionColumn={selectionColumn} rowIndex={ids.length + 2} />} </div> </div> ) return ( <div ref={rootRef} role="grid" data-slot="tradecn-data-grid" data-preset={props.preset ?? "blotter"} data-editable={edits ? "" : undefined} tabIndex={0} aria-label={label} aria-rowcount={ids.length + (footer ? 2 : 1)} aria-colcount={resolved.length + (selectionColumn ? 1 : 0)} aria-multiselectable={selectionMode === "multi" || undefined} aria-activedescendant={focusedRowId !== null && indexOf.has(focusedRowId) ? domId(focusedRowId) : undefined} onKeyDown={onKeyDown} className={cn("relative flex h-full min-h-0 flex-col overflow-hidden rounded-md border border-border bg-background text-foreground outline-none focus-visible:ring-2 focus-visible:ring-ring/40 lining-nums tabular-nums", preset.fontClass, className)} style={{ lineHeight: `${rowHeight}px` } as CSSProperties} > {renderContextMenu ? ( <ContextMenu> <ContextMenuTrigger className="contents">{body}</ContextMenuTrigger> <ContextMenuContent>{renderContextMenu(contextRows.rows, contextRows.ids)}</ContextMenuContent> </ContextMenu> ) : ( body )} {behind > 0 && ( <button type="button" data-grid-behind={behind} onClick={toTail} className="absolute left-1/2 z-30 -translate-x-1/2 rounded-full bg-primary px-2.5 py-0.5 text-primary-foreground shadow-sm hover:bg-primary/90" style={{ bottom: (footer ? rowHeight : 0) + 8 }} > {behind.toLocaleString()} new </button> )} {announceRowCount !== "off" && ( <div aria-live="polite" className="sr-only"> {announcement} </div> )} </div> ) } interface HeaderCellProps<T> { col: Resolved<T> colIndex: number left: number | undefined sort: "asc" | "desc" | null focused: boolean canMoveLeft: boolean canMoveRight: boolean hiddenCount: number onSort: () => void onFocus: () => void onHide: () => void onMove: (delta: -1 | 1) => void onReset: () => void onResize: (width: number) => void } function HeaderCell<T>(p: HeaderCellProps<T>) { const { col } = p const startResize = (e: PointerEvent<HTMLDivElement>) => { e.preventDefault() e.stopPropagation() const startX = e.clientX const startW = col.width const move = (ev: globalThis.PointerEvent) => p.onResize(startW + ev.clientX - startX) const up = () => { window.removeEventListener("pointermove", move) window.removeEventListener("pointerup", up) } window.addEventListener("pointermove", move) window.addEventListener("pointerup", up) } const title = typeof col.header === "string" ? col.header : undefined return ( <div role="columnheader" aria-colindex={p.colIndex + 1} aria-sort={p.sort === "asc" ? "ascending" : p.sort === "desc" ? "descending" : col.sortable ? "none" : undefined} data-col={col.key} data-focused-col={p.focused || undefined} className={cn("group relative flex h-full min-w-0 items-center gap-1 px-2 font-medium select-none", alignClass(col), p.left !== undefined && "sticky z-30 bg-background", p.focused && "text-foreground")} style={p.left !== undefined ? { left: p.left } : undefined} onPointerDown={p.onFocus} > <span className={cn("min-w-0 flex-1 truncate", col.sortable && "cursor-pointer hover:text-foreground")} title={title} onClick={col.sortable ? p.onSort : undefined} > {col.header} {p.sort && <span aria-hidden className="ml-1">{p.sort === "asc" ? "\u25B2" : "\u25BC"}</span>} </span> <DropdownMenu> <DropdownMenuTrigger aria-label={`${title ?? col.key} column menu`} className="rounded px-1 text-muted-foreground opacity-0 hover:bg-muted hover:text-foreground focus-visible:opacity-100 group-hover:opacity-100 data-[popup-open]:opacity-100 data-[state=open]:opacity-100" > <svg aria-hidden width="10" height="10" viewBox="0 0 10 10" fill="currentColor"> <circle cx="5" cy="1.5" r="1.2" /> <circle cx="5" cy="5" r="1.2" /> <circle cx="5" cy="8.5" r="1.2" /> </svg> </DropdownMenuTrigger> <DropdownMenuContent align="end"> {col.sortable && <DropdownMenuItem onClick={p.onSort}>{p.sort === "asc" ? "Sort descending" : p.sort === "desc" ? "Clear sort" : "Sort ascending"}</DropdownMenuItem>} <DropdownMenuItem disabled={!p.canMoveLeft} onClick={() => p.onMove(-1)}> Move left </DropdownMenuItem> <DropdownMenuItem disabled={!p.canMoveRight} onClick={() => p.onMove(1)}> Move right </DropdownMenuItem> <DropdownMenuItem onClick={p.onHide}>Hide column</DropdownMenuItem> <DropdownMenuSeparator /> <DropdownMenuItem onClick={p.onReset}>Reset columns{p.hiddenCount ? ` (${p.hiddenCount} hidden)` : ""}</DropdownMenuItem> </DropdownMenuContent> </DropdownMenu> <div role="separator" aria-orientation="vertical" aria-label={`Resize ${title ?? col.key}`} onPointerDown={startResize} className="absolute top-0 right-0 h-full w-1.5 cursor-col-resize hover:bg-ring/40" /> </div> ) } function cssEscape(s: string): string { return typeof CSS !== "undefined" && typeof CSS.escape === "function" ? CSS.escape(s) : s.replace(/["\\]/g, "\\$&") }hooks/use-flash.ts import { useLayoutEffect, useRef, type RefObject } from "react" // Flash a cell when its value changes, colored by direction, without a React re-render per tick. // // The previous value lives outside React (per cell, or in a shared FlashMemory keyed by cell so a // virtualized row that scrolls back within the window resumes its flash instead of losing it). // The flash itself is a Web Animations API animation on the existing element: retriggering cancels // the previous one for free, and nothing is remounted. export type Direction = "up" | "down" | "flat" export interface FlashRecord { value: unknown /** Clock time of the last flash, or -Infinity when the cell has never flashed. */ at: number dir: Direction } export interface FlashMemory { get(key: string): FlashRecord | undefined set(key: string, record: FlashRecord): void /** Drop every record whose key starts with `prefix` (a grid calls it with the row id on remove). */ forget(prefix: string): void readonly size: number } /** Bounded, least-recently-set memory. `max` records; oldest are evicted first. */ export function createFlashMemory(max = 50_000): FlashMemory { const map = new Map<string, FlashRecord>() return { get: (key) => map.get(key), set(key, record) { if (map.has(key)) map.delete(key) map.set(key, record) if (map.size > max) map.delete(map.keys().next().value!) }, forget(prefix) { for (const key of map.keys()) if (key.startsWith(prefix)) map.delete(key) }, get size() { return map.size }, } } export type Compare = (prev: unknown, next: unknown) => number | null /** Numeric difference when both sides are finite numbers; 0 when identical; null for any other change. */ export const compareValues: Compare = (prev, next) => { if (typeof prev === "number" && typeof next === "number" && Number.isFinite(prev) && Number.isFinite(next)) return next - prev return Object.is(prev, next) ? 0 : null } /** Direction of a change. Zero is flat, never up. A non-numeric change is flat. */ export function directionOf(prev: unknown, next: unknown, compare: Compare = compareValues): Direction { const d = compare(prev, next) if (d === null || d === 0) return "flat" return d > 0 ? "up" : "down" } export interface FlashOptions { /** How long a flash lasts, and how long a scrolled-away cell remembers it. Default 900. */ windowMs?: number /** `fill` tints the background; `ring` draws an inset outline, for cells that already carry a bar. */ variant?: "fill" | "ring" /** Paint with this instead of the direction's token: `var(--primary)` for an acknowledgement that has no direction. */ color?: string compare?: Compare /** * Flash flat when the same value arrives again. Needs `revision` to know it arrived: pass the row object * or the batch version, since an equal `value` alone looks unchanged to React. Default false. */ flashOnEqual?: boolean /** Anything that changes identity when a new reading arrives (the row object, a store version). */ revision?: unknown /** Shared memory across mounts; requires `cellKey`. */ memory?: FlashMemory cellKey?: string disabled?: boolean /** Injectable clock in ms; defaults to performance.now. */ now?: () => number } export const FILL_COLORS: Record<Direction, string> = { up: "var(--up-soft)", down: "var(--down-soft)", flat: "var(--flat-soft)", } export const RING_COLORS: Record<Direction, string> = { up: "var(--up)", down: "var(--down)", flat: "var(--flat)", } /** Tailwind classes for coloring a value by direction: text-up, text-down, text-flat. */ export function directionClass(dir: Direction | null | undefined): string { return dir === "up" ? "text-up" : dir === "down" ? "text-down" : "text-flat" } const animations = new WeakMap<Element, Animation>() const clearTimers = new WeakMap<Element, ReturnType<typeof setTimeout>>() let reducedMotion: boolean | null = null function prefersReducedMotion(): boolean { if (reducedMotion === null) { reducedMotion = typeof matchMedia === "function" ? matchMedia("(prefers-reduced-motion: reduce)").matches : false } return reducedMotion } /** Test hook: forget the cached media query. */ export function resetReducedMotionCache() { reducedMotion = null } function keyframes(dir: Direction, variant: "fill" | "ring", color?: string): Keyframe[] { if (variant === "ring") return [{ boxShadow: `inset 0 0 0 1px ${color ?? RING_COLORS[dir]}` }, { boxShadow: "inset 0 0 0 1px transparent" }] return [{ backgroundColor: color ?? FILL_COLORS[dir] }, { backgroundColor: "transparent" }] } /** Start (or resume, `elapsed` ms in) a flash on an element. */ export function playFlash(el: HTMLElement, dir: Direction, opts: { windowMs: number; variant: "fill" | "ring"; color?: string; elapsed?: number }) { const elapsed = Math.max(0, Math.min(opts.elapsed ?? 0, opts.windowMs)) animations.get(el)?.cancel() const pending = clearTimers.get(el) if (pending) clearTimeout(pending) el.dataset.direction = dir const done = () => { if (el.dataset.direction === dir) delete el.dataset.direction } if (prefersReducedMotion() || typeof el.animate !== "function") { // Static color from the data-direction styles, cleared when the window ends. clearTimers.set(el, setTimeout(done, opts.windowMs - elapsed)) return } const anim = el.animate(keyframes(dir, opts.variant, opts.color), { duration: opts.windowMs, easing: "ease-out", fill: "none" }) anim.currentTime = elapsed anim.onfinish = () => { if (animations.get(el) === anim) animations.delete(el) done() } animations.set(el, anim) } const NEVER: FlashRecord = { value: undefined, at: -Infinity, dir: "flat" } export function useFlash<E extends HTMLElement>(ref: RefObject<E | null>, value: unknown, opts: FlashOptions = {}): void { const { windowMs = 900, variant = "fill", color, compare = compareValues, flashOnEqual = false, memory, cellKey, disabled = false, revision } = opts const now = opts.now ?? (() => performance.now()) const local = useRef<FlashRecord | undefined>(undefined) const key = memory ? cellKey : undefined if (memory && !cellKey) throw new Error("useFlash: a shared memory needs a cellKey") const read = (): FlashRecord | undefined => (key !== undefined ? memory!.get(key) : local.current) const write = (record: FlashRecord) => { if (key !== undefined) memory!.set(key, record) else local.current = record } useLayoutEffect(() => { const el = ref.current if (!el || disabled) return const t = now() const prev = read() if (!prev) { // First sight of this cell: remember, do not flash. write({ ...NEVER, value }) return } const changed = !Object.is(prev.value, value) if (changed || flashOnEqual) { const dir = changed ? directionOf(prev.value, value, compare) : "flat" write({ value, at: t, dir }) playFlash(el, dir, { windowMs, variant, color }) return } // Same value on a fresh mount (a virtualized row scrolled back): resume a flash still in its window. const elapsed = t - prev.at if (elapsed < windowMs) playFlash(el, prev.dir, { windowMs, variant, color, elapsed }) // eslint-disable-next-line react-hooks/exhaustive-deps }, [value, revision, ref, disabled, windowMs, variant, color, flashOnEqual, compare, memory, key]) useLayoutEffect(() => { const el = ref.current return () => { if (!el) return animations.get(el)?.cancel() animations.delete(el) const pending = clearTimers.get(el) if (pending) clearTimeout(pending) } }, [ref]) }hooks/use-row-store.ts import { useCallback, useEffect, useRef, useState, useSyncExternalStore } from "react" import type { RowId, RowStore, RowView, StoreMeta, ViewOptions } from "@/lib/row-store" /** One row. The component re-renders when this row is replaced or patched, and for nothing else. */ export function useRow<T>(store: RowStore<T>, id: RowId): T | undefined { const subscribe = useCallback((cb: () => void) => store.subscribeRow(id, cb), [store, id]) const get = useCallback(() => store.getRow(id), [store, id]) return useSyncExternalStore(subscribe, get, get) } /** The ids of a store (insertion or authoritative order) or of a view (filtered, sorted, held). */ export function useRowIds<T>(source: RowStore<T> | RowView<T>): readonly RowId[] { const subscribe = useCallback((cb: () => void) => ("subscribeOrder" in source ? source.subscribeOrder(cb) : source.subscribe(cb)), [source]) const get = useCallback(() => source.getIds(), [source]) return useSyncExternalStore(subscribe, get, get) } /** Version, size, lane, drop count, sequence, gap, and timestamps. Changes once per batch. */ export function useStoreMeta<T>(store: RowStore<T>): StoreMeta { const subscribe = useCallback((cb: () => void) => store.subscribeMeta(cb), [store]) const get = useCallback(() => store.getMeta(), [store]) return useSyncExternalStore(subscribe, get, get) } /** * A view this component owns: made for the options given, disposed on the way out, and made again for * new options. Keep the options object's identity stable (a `useMemo`), since a new object is a new view. * Null options give null, for a component that takes a view from its props instead. * * Why a hook and not a memo with a dispose effect: React's StrictMode mounts, unmounts, and mounts a * component again in development, and the cleanup of that rehearsal disposes the memo's view while the * memo keeps handing it out, so the grid stopped following its store until something remade the view. * The effect here notices a disposed view and makes another. */ export function useView<T>(store: RowStore<T>, options: ViewOptions<T> | null): RowView<T> | null { const [view, setView] = useState<RowView<T> | null>(() => (options ? store.createView(options) : null)) const made = useRef({ store, options, view }) useEffect(() => { let current = made.current.view if (made.current.store !== store || made.current.options !== options || (current !== null && current.isDisposed())) { current = options ? store.createView(options) : null made.current = { store, options, view: current } // A view the rehearsal disposed, or new options: the replacement is state so the render that reads it re-runs. setView(current) } return () => current?.dispose() }, [store, options]) return view }lib/row-store.ts // A row store that React components subscribe to one row at a time. // // The consumer owns the feed. It calls `applyDeltas` once per frame with everything that changed // (a Tauri consumer straight from its event listener; a WebSocket consumer through `createFrameBatcher`). // A delta to one row wakes that row's subscribers and nobody else, and React batches every // notification fired inside one `applyDeltas` into one commit, so a batch of two thousand row // changes is one render pass over the rows that changed. // // Views sit on top: a filtered, sorted list of ids with an optional reorder hold so rows do not // move under a trader's cursor while they work. export type RowId = string /** How the lane loses data. `coalesced` drops stale ticks and counts them; `ordered` never drops. */ export type Lane = "coalesced" | "ordered" export interface DeltaBatch<T> { /** Whole rows. Replaces the row object, so every subscriber of that row wakes. */ upsert?: readonly T[] /** Partial rows merged into a new object. Unknown ids are ignored. */ patch?: readonly { id: RowId; fields: Partial<T> }[] remove?: readonly RowId[] /** Authoritative order for an ordered lane. Ids not present keep their previous relative order at the end. */ order?: readonly RowId[] meta?: { lane?: Lane /** Messages the producer dropped since the last batch (coalesced lane). Accumulated. */ dropped?: number /** Last sequence number applied (ordered lane). */ seq?: number /** A gap was detected and replay is in progress. */ gap?: boolean /** Producer timestamp of the newest message in the batch, ms since epoch. */ producedAt?: number } } export interface StoreMeta { /** Increments once per applied batch. */ version: number size: number lane: Lane dropped: number seq: number | null gap: boolean /** Wall clock of the last applied batch, ms since epoch. */ lastBatchAt: number | null producedAt: number | null } export interface ViewOptions<T> { comparator?: (a: T, b: T) => number filter?: (row: T) => boolean /** * After `touch()` (the grid calls it on every key and pointer interaction) the order is frozen for this * long: new rows append, removed rows vanish, nothing moves. 0 disables the hold. */ reorderHoldMs?: number /** Injectable clock, ms. Defaults to Date.now. */ now?: () => number } export interface RowView<T> { /** The store this view reads from. */ readonly store: RowStore<T> /** Stable array reference until the order actually changes. */ getIds(): readonly RowId[] subscribe(cb: () => void): () => void /** The user interacted; start or extend the reorder hold. */ touch(): void /** True while a hold is in force. */ isHeld(): boolean dispose(): void /** True after `dispose`: the view no longer follows the store. */ isDisposed(): boolean } export interface RowStore<T> { /** Stable object reference until the row is replaced or patched. */ getRow(id: RowId): T | undefined /** Stable array reference until the order changes. Insertion order unless a batch carries `order`. */ getIds(): readonly RowId[] /** Stable object reference until the next batch. */ getMeta(): StoreMeta subscribeRow(id: RowId, cb: () => void): () => void subscribeOrder(cb: () => void): () => void subscribeMeta(cb: () => void): () => void /** Apply one batch synchronously. Call it once per frame. */ applyDeltas(batch: DeltaBatch<T>): void createView(opts?: ViewOptions<T>): RowView<T> /** Drop every row (a re-snapshot is coming). Wakes every subscriber. */ clear(): void readonly getRowId: (row: T) => RowId } export interface RowStoreOptions<T> { getRowId: (row: T) => RowId lane?: Lane now?: () => number } type Listener = () => void export function createRowStore<T>(options: RowStoreOptions<T>): RowStore<T> { const { getRowId } = options const now = options.now ?? Date.now const rows = new Map<RowId, T>() let ids: RowId[] = [] let idsSnapshot: readonly RowId[] = ids let meta: StoreMeta = { version: 0, size: 0, lane: options.lane ?? "coalesced", dropped: 0, seq: null, gap: false, lastBatchAt: null, producedAt: null } const rowListeners = new Map<RowId, Set<Listener>>() const orderListeners = new Set<Listener>() const metaListeners = new Set<Listener>() const views = new Set<ViewImpl<T>>() function notifyRow(id: RowId) { const set = rowListeners.get(id) if (set) for (const cb of set) cb() } function applyDeltas(batch: DeltaBatch<T>) { const touched = new Set<RowId>() const removed = new Set<RowId>() let orderChanged = false if (batch.upsert) { for (const row of batch.upsert) { const id = getRowId(row) if (!rows.has(id)) { ids.push(id) orderChanged = true } rows.set(id, row) touched.add(id) } } if (batch.patch) { for (const { id, fields } of batch.patch) { const existing = rows.get(id) if (existing === undefined) continue rows.set(id, { ...existing, ...fields }) touched.add(id) } } if (batch.remove?.length) { const drop = new Set<RowId>() for (const id of batch.remove) { if (rows.delete(id)) { drop.add(id) removed.add(id) touched.add(id) } } if (drop.size) { ids = ids.filter((id) => !drop.has(id)) orderChanged = true } } if (batch.order) { const next: RowId[] = [] const seen = new Set<RowId>() for (const id of batch.order) { if (rows.has(id) && !seen.has(id)) { next.push(id) seen.add(id) } } for (const id of ids) if (!seen.has(id)) next.push(id) if (!sameOrder(ids, next)) { ids = next orderChanged = true } } const m = batch.meta meta = { version: meta.version + 1, size: rows.size, lane: m?.lane ?? meta.lane, dropped: meta.dropped + (m?.dropped ?? 0), seq: m?.seq ?? meta.seq, gap: m?.gap ?? meta.gap, lastBatchAt: now(), producedAt: m?.producedAt ?? meta.producedAt, } if (orderChanged) idsSnapshot = ids.slice() for (const view of views) view.onBatch(touched, removed, orderChanged) for (const id of touched) notifyRow(id) if (orderChanged) for (const cb of orderListeners) cb() for (const cb of metaListeners) cb() } const store: RowStore<T> = { getRowId, getRow: (id) => rows.get(id), getIds: () => idsSnapshot, getMeta: () => meta, subscribeRow(id, cb) { let set = rowListeners.get(id) if (!set) rowListeners.set(id, (set = new Set())) set.add(cb) return () => { set!.delete(cb) if (!set!.size) rowListeners.delete(id) } }, subscribeOrder(cb) { orderListeners.add(cb) return () => orderListeners.delete(cb) }, subscribeMeta(cb) { metaListeners.add(cb) return () => metaListeners.delete(cb) }, applyDeltas, createView(opts = {}) { const view = new ViewImpl<T>(store, opts, () => views.delete(view)) views.add(view) return view }, clear() { const all = ids rows.clear() ids = [] idsSnapshot = ids meta = { ...meta, version: meta.version + 1, size: 0, lastBatchAt: now() } for (const view of views) view.onBatch(new Set(all), new Set(all), true) for (const id of all) notifyRow(id) for (const cb of orderListeners) cb() for (const cb of metaListeners) cb() }, } return store } function sameOrder(a: readonly RowId[], b: readonly RowId[]): boolean { if (a.length !== b.length) return false for (let i = 0; i < a.length; i++) if (a[i] !== b[i]) return false return true } class ViewImpl<T> implements RowView<T> { private ids: readonly RowId[] = [] private readonly listeners = new Set<Listener>() private holdUntil = 0 private timer: ReturnType<typeof setTimeout> | null = null private disposed = false private readonly now: () => number readonly store: RowStore<T> private readonly opts: ViewOptions<T> private readonly onDispose: () => void constructor(store: RowStore<T>, opts: ViewOptions<T>, onDispose: () => void) { this.store = store this.opts = opts this.onDispose = onDispose this.now = opts.now ?? Date.now this.ids = this.compute() } getIds() { return this.ids } subscribe(cb: Listener) { this.listeners.add(cb) return () => { this.listeners.delete(cb) } } isHeld() { return this.now() < this.holdUntil } touch() { const hold = this.opts.reorderHoldMs ?? 0 if (hold <= 0) return this.holdUntil = this.now() + hold if (this.timer) clearTimeout(this.timer) // A quiet feed still settles: recompute when the hold lapses. this.timer = setTimeout(() => { this.timer = null this.set(this.compute()) }, hold) } dispose() { if (this.disposed) return this.disposed = true if (this.timer) clearTimeout(this.timer) this.listeners.clear() this.onDispose() } isDisposed() { return this.disposed } /** Called by the store inside applyDeltas, before row listeners fire. */ onBatch(touched: Set<RowId>, removed: Set<RowId>, orderChanged: boolean) { if (!touched.size && !orderChanged) return if (this.isHeld()) { // Frozen order: keep what is there, drop removals and rows that no longer pass the filter, append newcomers. const present = new Set(this.ids) const kept = this.ids.filter((id) => !removed.has(id) && this.passes(id)) const newcomers = this.store.getIds().filter((id) => !present.has(id) && this.passes(id)) if (this.opts.comparator) newcomers.sort(this.compare) const next = kept.length === this.ids.length && !newcomers.length ? this.ids : [...kept, ...newcomers] this.set(next) return } // Only recompute when the batch could have changed this view. let relevant = orderChanged if (!relevant) for (const id of touched) if (this.passes(id) || this.ids.includes(id)) { relevant = true; break } if (relevant) this.set(this.compute()) } private passes(id: RowId): boolean { const row = this.store.getRow(id) if (row === undefined) return false return this.opts.filter ? this.opts.filter(row) : true } private readonly compare = (a: RowId, b: RowId) => this.opts.comparator!(this.store.getRow(a)!, this.store.getRow(b)!) private compute(): readonly RowId[] { const all = this.store.getIds() const list = this.opts.filter ? all.filter((id) => this.passes(id)) : all.slice() if (this.opts.comparator) list.sort(this.compare) return list } private set(next: readonly RowId[]) { if (sameOrder(this.ids, next)) return this.ids = next for (const cb of this.listeners) cb() } } export interface FrameBatcher<T> { /** Queue a delta; the merged batch applies on the next animation frame. */ push(delta: DeltaBatch<T>): void /** Apply now, without waiting for the frame. */ flush(): void /** Drop everything queued. */ cancel(): void pending(): boolean } /** * Coalesce many small deltas into one batch per frame, last write wins per row. For consumers whose * feed delivers messages one at a time. A consumer whose core already batches per frame calls * `applyDeltas` directly and skips this: another frame of latency buys nothing. */ export function createFrameBatcher<T>( apply: (batch: DeltaBatch<T>) => void, options: { getRowId: (row: T) => RowId; raf?: (cb: () => void) => number; caf?: (handle: number) => void }, ): FrameBatcher<T> { const raf = options.raf ?? ((cb) => requestAnimationFrame(cb)) const caf = options.caf ?? ((h) => (typeof cancelAnimationFrame === "function" ? cancelAnimationFrame(h) : undefined)) const upserts = new Map<RowId, T>() const patches = new Map<RowId, Partial<T>>() const removes = new Set<RowId>() let order: readonly RowId[] | undefined let meta: NonNullable<DeltaBatch<T>["meta"]> | undefined let handle: number | null = null function reset() { upserts.clear() patches.clear() removes.clear() order = undefined meta = undefined } function flush() { if (handle !== null) { caf(handle) handle = null } if (!upserts.size && !patches.size && !removes.size && !order && !meta) return const batch: DeltaBatch<T> = {} if (upserts.size) batch.upsert = [...upserts.values()] if (patches.size) batch.patch = [...patches].map(([id, fields]) => ({ id, fields })) if (removes.size) batch.remove = [...removes] if (order) batch.order = order if (meta) batch.meta = meta reset() apply(batch) } return { push(delta) { for (const row of delta.upsert ?? []) { const id = options.getRowId(row) removes.delete(id) patches.delete(id) upserts.set(id, row) } for (const { id, fields } of delta.patch ?? []) { if (removes.has(id)) continue const pendingUpsert = upserts.get(id) if (pendingUpsert !== undefined) upserts.set(id, { ...pendingUpsert, ...fields }) else patches.set(id, { ...(patches.get(id) ?? {}), ...fields }) } for (const id of delta.remove ?? []) { upserts.delete(id) patches.delete(id) removes.add(id) } if (delta.order) order = delta.order if (delta.meta) { meta = { ...meta, ...delta.meta, dropped: (meta?.dropped ?? 0) + (delta.meta.dropped ?? 0), gap: Boolean(meta?.gap) || Boolean(delta.meta.gap), } } if (handle === null) { handle = raf(() => { handle = null flush() }) } }, flush, cancel() { if (handle !== null) caf(handle) handle = null reset() }, pending: () => handle !== null, } }lib/format.ts // Number formatting for trading screens. Pure functions, no React, no dependencies. // Every formatter returns NULL_TOKEN for null, undefined, NaN, and infinities, so a grid // never prints "NaN" or "undefined" while a feed is warming up. export const NULL_TOKEN = "–" const MINUS = "−" export type Nullable = number | null | undefined export interface Locale { /** BCP 47 tag; defaults to en-US. */ locale?: string } export type PriceConvention = /** Fixed decimals, e.g. equities at 2. */ | { kind: "decimal"; decimals: number } /** Decimals derived from the instrument's tick size, e.g. 0.001 gives 3. */ | { kind: "tick"; tick: number } /** * Fractional quoting. `denominator` 32 or 64; `half` renders a half tick as "+" (99-16+) or "5" (99-165); * `eighths` renders eighths of a tick as a trailing digit (99-162 is 99 and 16 2/8 thirty-seconds). */ | { kind: "fraction"; denominator: 32 | 64; half: "+" | "5"; eighths?: boolean } /** What a quote is typed and read in. Bills quote on discount, most bonds on price, some on yield, credit often on a spread in basis points. */ export type QuoteBasis = "price" | "yield" | "discount" | "spread" export interface InstrumentConvention { price: PriceConvention /** Smallest price increment, used for stepping and rounding. */ tick: number yieldDecimals?: number quantityUnit?: "notional" | "contracts" /** Default price. */ quoteBasis?: QuoteBasis /** What a quote steps by in its basis. Default: the tick for price, 0.001 for yield and discount, 0.1 for spread. */ quoteStep?: number /** Decimals for a yield, discount, or spread quote. Default 3, 3, and 1. Price quotes follow their convention. */ quoteDecimals?: number } function isNil(v: Nullable): v is null | undefined { return v === null || v === undefined || !Number.isFinite(v) } // One Intl.NumberFormat per locale and option set; construction is the expensive part. const formatters = new Map<string, Intl.NumberFormat>() export function numberFormat(locale: string | undefined, options: Intl.NumberFormatOptions): Intl.NumberFormat { const key = `${locale ?? "en-US"}|${JSON.stringify(options)}` let nf = formatters.get(key) if (!nf) { nf = new Intl.NumberFormat(locale ?? "en-US", options) formatters.set(key, nf) } return nf } function fixed(v: number, decimals: number, locale?: string, extra: Intl.NumberFormatOptions = {}): string { return numberFormat(locale, { minimumFractionDigits: decimals, maximumFractionDigits: decimals, ...extra }).format(v) } function typographicMinus(s: string): string { return s.replace(/-/g, MINUS) } /** Decimal places needed to show a price on this tick grid. 0.001 gives 3, 1/32 gives 5, 1 gives 0. Capped at `max`. */ export function decimalsFromTick(tick: number, max = 8): number { if (!Number.isFinite(tick) || tick <= 0) return 0 for (let d = 0; d <= max; d++) { const scaled = tick * 10 ** d if (Math.abs(scaled - Math.round(scaled)) < 1e-9 * Math.max(1, scaled)) return d } return max } /** Nearest price on the tick grid, cleaned of float noise. */ export function roundToTick(v: number, tick: number): number { if (!Number.isFinite(v) || !Number.isFinite(tick) || tick <= 0) return v return Number((Math.round(v / tick) * tick).toFixed(decimalsFromTick(tick))) } /** Move `steps` ticks (negative allowed) from the nearest grid price. */ export function stepByTick(v: number, tick: number, steps: number): number { return roundToTick(roundToTick(v, tick) + steps * tick, tick) } /** Whole-number and sub-tick decomposition on an integer grid so 32nds never drift. */ function decomposeFraction(v: number, c: Extract<PriceConvention, { kind: "fraction" }>) { const sub = c.eighths ? 8 : 2 const unitsPerWhole = c.denominator * sub const total = Math.round(Math.abs(v) * unitsPerWhole) const whole = Math.floor(total / unitsPerWhole) const rem = total - whole * unitsPerWhole const ticks = Math.floor(rem / sub) const subticks = rem - ticks * sub return { negative: v < 0 && total > 0, whole, ticks, subticks, sub } } /** 99.515625 as "99-16+" (32nds, half "+"), "99-165" (half "5"), or "99-164" with eighths. */ export function formatFraction(v: Nullable, c: Extract<PriceConvention, { kind: "fraction" }>): string { if (isNil(v)) return NULL_TOKEN const { negative, whole, ticks, subticks, sub } = decomposeFraction(v, c) let tail = "" if (subticks !== 0) { if (c.eighths) tail = String(subticks) else tail = c.half } void sub return `${negative ? MINUS : ""}${whole}-${String(ticks).padStart(2, "0")}${tail}` } export function formatPrice(v: Nullable, c: PriceConvention, l?: Locale): string { if (isNil(v)) return NULL_TOKEN switch (c.kind) { case "decimal": return typographicMinus(fixed(v, c.decimals, l?.locale)) case "tick": return typographicMinus(fixed(roundToTick(v, c.tick), decimalsFromTick(c.tick), l?.locale)) case "fraction": return formatFraction(v, c) } } /** * Inverse of formatPrice for ticket entry. Accepts the convention's own notation and a plain decimal. * Returns null when the text is not a price. Fraction input: "99-16+", "99-165", "99-162", "99-16", "99". */ export function parsePrice(s: string, c: PriceConvention): number | null { const text = s.trim().replace(/−/g, "-").replace(/,/g, "") if (!text) return null if (c.kind === "fraction") { const m = /^([+-]?)(\d+)(?:-(\d{1,2})([+0-9])?)?$/.exec(text) if (m) { const [, sign, wholeText, ticksText, tail] = m const ticks = ticksText ? Number(ticksText) : 0 if (ticks >= c.denominator) return null let subFraction = 0 if (tail === "+") subFraction = 0.5 else if (tail !== undefined) { const digit = Number(tail) if (c.eighths) { if (digit > 7) return null subFraction = digit / 8 } else if (c.half === "5" && digit === 5) subFraction = 0.5 else if (digit === 0) subFraction = 0 else return null } const value = Number(wholeText) + (ticks + subFraction) / c.denominator return sign === "-" ? -value : value } } if (!/^[+-]?(\d+\.?\d*|\.\d+)$/.test(text)) return null const n = Number(text) if (!Number.isFinite(n)) return null if (c.kind === "tick") return roundToTick(n, c.tick) if (c.kind === "decimal") return Number(n.toFixed(c.decimals)) return n } /** 4.2531 as "4.253%". */ export function formatYield(v: Nullable, o: { decimals?: number; suffix?: "%" | "" } & Locale = {}): string { if (isNil(v)) return NULL_TOKEN return typographicMinus(fixed(v, o.decimals ?? 3, o.locale)) + (o.suffix ?? "%") } /** 12.5 as "12.5 bp"; signed gives "+12.5 bp". */ export function formatBps(v: Nullable, o: { decimals?: number; signed?: boolean; unit?: "bp" | "bps" | "" } & Locale = {}): string { if (isNil(v)) return NULL_TOKEN const unit = o.unit ?? "bp" const body = o.signed ? formatSigned(v, { decimals: o.decimals ?? 1, locale: o.locale }) : typographicMinus(fixed(v, o.decimals ?? 1, o.locale)) return unit ? `${body} ${unit}` : body } /** Dollar value of a basis point as whole currency; compact gives "$1.23K". */ export function formatDv01(v: Nullable, o: { currency?: string; compact?: boolean } & Locale = {}): string { if (isNil(v)) return NULL_TOKEN const currency = o.currency ?? "USD" if (o.compact) { const symbol = numberFormat(o.locale, { style: "currency", currency, currencyDisplay: "narrowSymbol", maximumFractionDigits: 0 }) .formatToParts(0) .find((p) => p.type === "currency")?.value ?? "" return `${v < 0 ? MINUS : ""}${symbol}${formatNotional(Math.abs(v), { compact: true, locale: o.locale })}` } return typographicMinus(numberFormat(o.locale, { style: "currency", currency, currencyDisplay: "narrowSymbol", maximumFractionDigits: 0 }).format(v)) } /** 1250000 as "1.25M" (compact), "1.25mm" (unit "mm", the desk's word for millions, never scaled further), or "1,250,000.00". Compact suffixes K, M, B, T. */ export function formatNotional(v: Nullable, o: { compact?: boolean; decimals?: number; unit?: "mm" } & Locale = {}): string { if (isNil(v)) return NULL_TOKEN const decimals = o.decimals ?? 2 if (o.unit === "mm") return typographicMinus(numberFormat(o.locale, { minimumFractionDigits: 0, maximumFractionDigits: decimals }).format(v / 1e6)) + "mm" if (!o.compact) return typographicMinus(fixed(v, decimals, o.locale)) const abs = Math.abs(v) const [divisor, suffix] = abs >= 1e12 ? [1e12, "T"] : abs >= 1e9 ? [1e9, "B"] : abs >= 1e6 ? [1e6, "M"] : abs >= 1e3 ? [1e3, "K"] : [1, ""] return typographicMinus(fixed(v / divisor, suffix ? decimals : 0, o.locale)) + suffix } /** "+0.12", "−0.12" (U+2212), and "0.00" for zero: flat carries no sign. */ export function formatSigned(v: Nullable, o: { decimals?: number } & Locale = {}): string { if (isNil(v)) return NULL_TOKEN return typographicMinus(fixed(v, o.decimals ?? 2, o.locale, { signDisplay: "exceptZero" })) } /** 1.234 as "1.23%"; signed gives "+1.23%". */ export function formatPercent(v: Nullable, o: { decimals?: number; signed?: boolean } & Locale = {}): string { if (isNil(v)) return NULL_TOKEN const decimals = o.decimals ?? 2 return (o.signed ? formatSigned(v, { decimals, locale: o.locale }) : typographicMinus(fixed(v, decimals, o.locale))) + "%" } /** Whole quantities with grouping: 1000000 as "1,000,000". */ export function formatQuantity(v: Nullable, l?: Locale): string { if (isNil(v)) return NULL_TOKEN return typographicMinus(fixed(Math.round(v), 0, l?.locale)) } /** * A coupon the way a run prints it: 4.125 as "4 1/8", 4.5 as "4 1/2", 4 as "4", 0 as "0" (coupons step in eighths). * One off the eighths grid prints as a plain decimal, "4.1". `style: "decimal"` prints "4.125%". */ export function formatCoupon(v: Nullable, o: { style?: "fraction" | "decimal"; decimals?: number } & Locale = {}): string { if (isNil(v)) return NULL_TOKEN if (o.style === "decimal") return typographicMinus(fixed(v, o.decimals ?? 3, o.locale)) + "%" const eighths = Math.round(Math.abs(v) * 8) if (Math.abs(eighths / 8 - Math.abs(v)) > 1e-9) return typographicMinus(numberFormat(o.locale, { minimumFractionDigits: 0, maximumFractionDigits: o.decimals ?? 3 }).format(v)) const whole = Math.floor(eighths / 8) const rem = eighths % 8 const fraction = rem === 0 ? "" : rem % 4 === 0 ? "1/2" : rem % 2 === 0 ? `${rem / 2}/4` : `${rem}/8` const body = fraction ? (whole ? `${whole} ${fraction}` : fraction) : String(whole) return `${v < 0 && eighths > 0 ? MINUS : ""}${body}` } /** A date as an instant, a millisecond count, or a string `Date` can read. A date-only string ("2034-05-15") is that day in UTC. */ export type DateLike = Date | number | string function toDate(d: DateLike | null | undefined): Date | null { if (d === null || d === undefined) return null const date = d instanceof Date ? d : new Date(d) return Number.isNaN(date.getTime()) ? null : date } const dateFormatters = new Map<string, Intl.DateTimeFormat>() /** * A maturity as a run prints it: "05/15/34", or "05/15/2034" with `year: "numeric"`. Read in UTC, so a * date-only string prints as that day wherever the screen is. */ export function formatMaturity(d: DateLike | null | undefined, o: { year?: "2-digit" | "numeric" } & Locale = {}): string { const date = toDate(d) if (!date) return NULL_TOKEN const key = `${o.locale ?? "en-US"}|${o.year ?? "2-digit"}` let f = dateFormatters.get(key) if (!f) { f = new Intl.DateTimeFormat(o.locale ?? "en-US", { month: "2-digit", day: "2-digit", year: o.year ?? "2-digit", timeZone: "UTC" }) dateFormatters.set(key, f) } return f.format(date) } /** Whole UTC days from `now` (the moment, by default) to a maturity. Negative once it has passed; null when the date does not read. */ export function daysToMaturity(d: DateLike | null | undefined, now: DateLike = Date.now()): number | null { const maturity = toDate(d) const from = toDate(now) if (!maturity || !from) return null const day = (x: Date) => Date.UTC(x.getUTCFullYear(), x.getUTCMonth(), x.getUTCDate()) return Math.round((day(maturity) - day(from)) / 86_400_000) } /** How many ticks `a` is from `b`, signed, to the nearest eighth of a tick: 99-17 against 99-16+ on a 1/64 tick is 1. NaN when a side is not a number or the tick is not positive. */ export function ticksBetween(a: number, b: number, tick: number): number { if (!Number.isFinite(a) || !Number.isFinite(b) || !(tick > 0)) return NaN return Math.round(((a - b) / tick) * 8) / 8 } /** A count of ticks: "+1", "−0.5", "0", up to three decimals and no trailing zeros. Signed unless told otherwise; `unit` adds a word. */ export function formatTicks(v: Nullable, o: { signed?: boolean; unit?: string } & Locale = {}): string { if (isNil(v)) return NULL_TOKEN const body = typographicMinus(numberFormat(o.locale, { minimumFractionDigits: 0, maximumFractionDigits: 3, signDisplay: o.signed === false ? "auto" : "exceptZero" }).format(v)) return o.unit ? `${body} ${o.unit}` : body } /** * The class a number wears (contract rule 14): lining, tabular figures whatever the font, in the numeric family. * `--tradecn-font-numeric` is the sans by default, so letters stay proportional and only the digits take one * width, which is what a column of prices wants. docs/typography.md has the reasoning and the tokens. */ export const NUMERIC_CLASS = "font-(family-name:--tradecn-font-numeric) lining-nums tabular-nums" /** The same figures in the mono stack, `--tradecn-font-mono`: for a fraction quote, whose dash, ticks, and tail must line up down a column. */ export const MONO_NUMERIC_CLASS = "font-(family-name:--tradecn-font-mono) lining-nums tabular-nums" /** * The class for a number printed under a convention: a fraction price (99-16+) sets in the mono stack, so * 99-16+ over 99-17 keeps its dash and its tail in the same place; every other price, and every quote in * another basis, keeps the numeric family. */ export function numericFontClass(c?: PriceConvention | InstrumentConvention | null): string { const price = c && "price" in c ? (quoteBasisOf(c) === "price" ? c.price : null) : c return price?.kind === "fraction" ? MONO_NUMERIC_CLASS : NUMERIC_CLASS } /** The word for a quote field's label, per basis. */ export const QUOTE_BASIS_LABELS: Record<QuoteBasis, string> = { price: "Price", yield: "Yield", discount: "Discount", spread: "Spread" } const QUOTE_DEFAULTS: Record<Exclude<QuoteBasis, "price">, { step: number; decimals: number }> = { yield: { step: 0.001, decimals: 3 }, discount: { step: 0.001, decimals: 3 }, spread: { step: 0.1, decimals: 1 }, } export function quoteBasisOf(c: InstrumentConvention): QuoteBasis { return c.quoteBasis ?? "price" } /** What a quote steps by in its basis: the tick for a price, else `quoteStep` or the basis default. */ export function quoteStepOf(c: InstrumentConvention): number { const basis = quoteBasisOf(c) return basis === "price" ? c.tick : (c.quoteStep ?? QUOTE_DEFAULTS[basis].step) } function quoteDecimalsOf(c: InstrumentConvention): number { const basis = quoteBasisOf(c) return basis === "price" ? 0 : (c.quoteDecimals ?? QUOTE_DEFAULTS[basis].decimals) } /** A quote in the instrument's basis: a price by its convention, else a fixed decimal with the basis's decimals and no unit, since the field's label says the basis. */ export function formatQuote(v: Nullable, c: InstrumentConvention, l?: Locale): string { if (isNil(v)) return NULL_TOKEN if (quoteBasisOf(c) === "price") return formatPrice(v, c.price, l) return typographicMinus(fixed(roundToTick(v, quoteStepOf(c)), quoteDecimalsOf(c), l?.locale)) } /** Inverse of formatQuote for a quote field. A price takes its notation or a decimal; the others take a decimal and snap to the quote step. Null when the text is not a quote. */ export function parseQuote(s: string, c: InstrumentConvention): number | null { if (quoteBasisOf(c) === "price") return parsePrice(s, c.price) const text = s.trim().replace(/−/g, "-").replace(/,/g, "") if (!/^[+-]?(\d+\.?\d*|\.\d+)$/.test(text)) return null const n = Number(text) return Number.isFinite(n) ? roundToTick(n, quoteStepOf(c)) : null } /** Move a quote by `steps` of its step, from the nearest grid value. */ export function stepQuote(v: number, c: InstrumentConvention, steps: number): number { return stepByTick(v, quoteStepOf(c), steps) } /** Bind a convention once per instrument; a grid column calls `formatters[row.instrumentId].price(v)`, a quote field its `quote`, `parseQuote`, and `stepQuote`. */ export function createInstrumentFormatter(c: InstrumentConvention, l?: Locale) { return { tick: c.tick, basis: quoteBasisOf(c), quoteStep: quoteStepOf(c), price: (v: Nullable) => formatPrice(v, c.price, l), yield: (v: Nullable) => formatYield(v, { decimals: c.yieldDecimals ?? 3, locale: l?.locale }), step: (v: number, steps: number) => stepByTick(v, c.tick, steps), parsePrice: (s: string) => parsePrice(s, c.price), quantity: (v: Nullable) => formatQuantity(v, l), quote: (v: Nullable) => formatQuote(v, c, l), parseQuote: (s: string) => parseQuote(s, c), stepQuote: (v: number, steps: number) => stepQuote(v, c, steps), } }lib/grid-rules.ts // Rules as data for a grid: which cells to color, which rows to show, and the order, as plain objects // a desk's support staff can write without a build, compiled here into the functions the grid runs. // // A rule names a column by its key and reads a row through that column's own accessor. A value typed // into a rule is read in the column's own format through its `parse`, so a price rule on a 32nds // column is written the way the column prints, "99-16+". Tones are token names, never a literal // color, and an applied rule carries its meaning in a channel besides the color: `data-rule` names // the rule on the element and the rule's words go in the element's accessible description (contract // rule 15). Nothing here decides a value; it only compares what the row says with what the rule says. export type RuleOp = "eq" | "ne" | "gt" | "gte" | "lt" | "lte" | "between" | "in" | "contains" | "startsWith" | "isNull" | "notNull" /** What a rule compares against, as typed. A string is read in the column's format; a number or boolean is used as it is. */ export type RuleValue = string | number | boolean | null /** A token name. The soft variant tints the background; the token itself colors the text. */ export type RuleTone = "up" | "down" | "flat" | "stale" | "expiring" | "primary" | "destructive" export interface RuleCondition { op: RuleOp /** For eq, ne, gt, gte, lt, lte, contains, and startsWith. */ value?: RuleValue /** For between (two: low, then high, both inclusive) and in (any number). Each is read as `value` is. */ values?: RuleValue[] } export interface ColumnRule { id: string /** The column whose value the rule reads, by key. */ column: string when: RuleCondition tone: RuleTone /** The rule in words: the accessible description of what it paints. `describeRule` writes one when it is left out. */ label?: string /** What the tone paints: the cell in `column` (default), or the whole row. */ target?: "cell" | "row" } export interface FilterRule extends RuleCondition { column: string } export interface SortRule { key: string dir: "asc" | "desc" } export interface GridRules { /** Cells and rows to color. The first rule in the list that matches a cell decides it. */ columns?: ColumnRule[] /** Every rule has to hold for a row to show. */ filter?: FilterRule[] /** The first rule that tells two rows apart decides their order. */ sort?: SortRule[] } /** What a rule needs of a column. The grid's `ColumnDef` satisfies it. */ export interface RuleColumn<T> { key: string /** Named in a rule's words when it is a string; the key otherwise. */ header?: unknown accessor: (row: T) => unknown numeric?: boolean /** Reads a value typed into a rule in this column's own format. Default: a number for a numeric column, the text itself for the rest. */ parse?: (text: string) => unknown } export const RULE_OPS: readonly RuleOp[] = ["eq", "ne", "gt", "gte", "lt", "lte", "between", "in", "contains", "startsWith", "isNull", "notNull"] export const NUMBER_OPS: readonly RuleOp[] = ["eq", "ne", "gt", "gte", "lt", "lte", "between", "in", "isNull", "notNull"] export const TEXT_OPS: readonly RuleOp[] = ["eq", "ne", "contains", "startsWith", "in", "isNull", "notNull"] /** The word for each op, as a rule reads aloud: "Price above 99-16+". */ export const RULE_OP_LABELS: Record<RuleOp, string> = { eq: "is", ne: "is not", gt: "above", gte: "at or above", lt: "below", lte: "at or below", between: "between", in: "one of", contains: "contains", startsWith: "starts with", isNull: "is empty", notNull: "is not empty", } export const RULE_TONES: readonly RuleTone[] = ["up", "down", "flat", "stale", "expiring", "primary", "destructive"] // The text takes the token and the background a tint of its soft variant, painted as a background // image rather than a background color so it layers over whatever color the element already has: a // frozen cell keeps its opaque `bg-background` under the tint and stays opaque as rows scroll beneath // it, and a selected row's `bg-accent` shows through. Literal strings, so Tailwind finds them. export const RULE_TONE_CLASS: Record<RuleTone, string> = { up: "text-up bg-[linear-gradient(var(--up-soft),var(--up-soft))]", down: "text-down bg-[linear-gradient(var(--down-soft),var(--down-soft))]", flat: "text-flat bg-[linear-gradient(var(--flat-soft),var(--flat-soft))]", stale: "text-stale bg-[linear-gradient(var(--stale-soft),var(--stale-soft))]", expiring: "text-expiring bg-[linear-gradient(var(--expiring-soft),var(--expiring-soft))]", primary: "text-primary bg-[linear-gradient(color-mix(in_oklab,var(--primary)_12%,transparent),color-mix(in_oklab,var(--primary)_12%,transparent))]", destructive: "text-destructive bg-[linear-gradient(color-mix(in_oklab,var(--destructive)_12%,transparent),color-mix(in_oklab,var(--destructive)_12%,transparent))]", } /** What an applied rule puts on a cell or a row. */ export interface RuleDecoration { "data-rule": string "data-tone": RuleTone "aria-description": string className: string } /** The ops a column offers: comparisons and ranges for a numeric column, text matching for the rest. */ export function opsFor(column: { numeric?: boolean } | undefined): readonly RuleOp[] { return column?.numeric ? NUMBER_OPS : TEXT_OPS } /** The column's name in words: its header when that is a string, else its key. */ export function columnName<T>(column: RuleColumn<T> | undefined, key?: string): string { if (column && typeof column.header === "string" && column.header.trim()) return column.header return column?.key ?? key ?? "" } /** Null for null, undefined, NaN, and the infinities; the value otherwise. */ export function normalizeValue(value: unknown): unknown { if (value === null || value === undefined) return null if (typeof value === "number" && !Number.isFinite(value)) return null return value } /** Nulls last, numbers numerically, everything else as text. */ export function compareValues(a: unknown, b: unknown): number { const an = normalizeValue(a) === null const bn = normalizeValue(b) === null if (an && bn) return 0 if (an) return 1 if (bn) return -1 if (typeof a === "number" && typeof b === "number") return a - b return String(a).localeCompare(String(b)) } /** `compareValues` in a direction, with a null last whichever way the list runs: a missing price never leads a list sorted high to low. */ export function compareDirected(a: unknown, b: unknown, dir: "asc" | "desc"): number { const an = normalizeValue(a) === null const bn = normalizeValue(b) === null if (an || bn) return compareValues(a, b) const c = compareValues(a, b) return dir === "desc" ? -c : c } /** * A value as typed into a rule, read for a column: a string goes through the column's `parse`, or * `Number` for a numeric column, and stays text otherwise; a number or boolean is used as it is. * Null when there is nothing to read, and null never matches anything but `isNull`. */ export function readRuleValue<T>(column: RuleColumn<T> | undefined, raw: RuleValue | undefined): unknown { if (raw === undefined || raw === null) return null if (typeof raw !== "string") return normalizeValue(raw) if (column?.parse) return normalizeValue(column.parse(raw)) if (column?.numeric) { const text = raw.trim().replace(/−/g, "-").replace(/,/g, "") return text === "" ? null : normalizeValue(Number(text)) } return raw } function same(a: unknown, b: unknown): boolean { if (typeof a === "string" && typeof b === "string") return a.toLowerCase() === b.toLowerCase() if (typeof a === "number" && typeof b === "string") return a === Number(b) if (typeof a === "string" && typeof b === "number") return Number(a) === b return a === b } const needsValue = new Set<RuleOp>(["eq", "ne", "gt", "gte", "lt", "lte", "contains", "startsWith"]) /** * One condition compiled against one column: the typed values are read once, and the function that * comes back only compares. A row whose value is null answers only `isNull` and `notNull`. */ export function compileCondition<T>(condition: RuleCondition, column: RuleColumn<T>): (row: T) => boolean { const { op } = condition const want = readRuleValue(column, condition.value) const list = (condition.values ?? []).map((v) => readRuleValue(column, v)).filter((v) => v !== null) const read = (row: T) => normalizeValue(column.accessor(row)) switch (op) { case "isNull": return (row) => read(row) === null case "notNull": return (row) => read(row) !== null case "eq": return want === null ? () => false : (row) => same(read(row), want) case "ne": return want === null ? () => false : (row) => { const v = read(row) return v !== null && !same(v, want) } case "gt": case "gte": case "lt": case "lte": { if (want === null) return () => false return (row) => { const v = read(row) if (v === null) return false const c = compareValues(v, want) return op === "gt" ? c > 0 : op === "gte" ? c >= 0 : op === "lt" ? c < 0 : c <= 0 } } case "between": { const [lo, hi] = list if (lo === undefined || hi === undefined) return () => false return (row) => { const v = read(row) return v !== null && compareValues(v, lo) >= 0 && compareValues(v, hi) <= 0 } } case "in": return list.length === 0 ? () => false : (row) => list.some((item) => same(read(row), item)) case "contains": case "startsWith": { if (want === null) return () => false const needle = String(want).toLowerCase() return (row) => { const v = read(row) if (v === null) return false const text = String(v).toLowerCase() return op === "contains" ? text.includes(needle) : text.startsWith(needle) } } } } function findColumn<T>(columns: readonly RuleColumn<T>[], key: string): RuleColumn<T> | undefined { return columns.find((column) => column.key === key) } /** * Why a rule cannot apply, in a sentence, or null when it can: a column the grid does not have, a * value the column cannot read, a range without its two ends, a set with nothing in it. */ export function ruleProblem<T>(rule: { column: string; when?: RuleCondition } & Partial<RuleCondition>, columns: readonly RuleColumn<T>[]): string | null { const column = findColumn(columns, rule.column) if (!column) return `No column is named "${rule.column}".` const condition: RuleCondition = rule.when ?? { op: rule.op!, value: rule.value, values: rule.values } const name = columnName(column) const unreadable = (raw: RuleValue | undefined) => raw !== undefined && raw !== null && raw !== "" && readRuleValue(column, raw) === null if (needsValue.has(condition.op)) { if (condition.value === undefined || condition.value === null || condition.value === "") return `${RULE_OP_LABELS[condition.op]} needs a value.` if (unreadable(condition.value)) return `"${condition.value}" is not a value ${name} reads.` } if (condition.op === "between") { const values = condition.values ?? [] if (values.length !== 2) return "between needs a low value and a high value." for (const raw of values) if (unreadable(raw) || raw === "" || raw === null) return `"${raw ?? ""}" is not a value ${name} reads.` } if (condition.op === "in") { const values = (condition.values ?? []).filter((raw) => raw !== null && raw !== "") if (!values.length) return "one of needs at least one value." for (const raw of values) if (unreadable(raw)) return `"${raw}" is not a value ${name} reads.` } return null } /** The rule in words: "Price above 99-16+", "Client one of ALPHA, BETA", "Status is empty". */ export function describeRule<T>(rule: { column: string; when?: RuleCondition } & Partial<RuleCondition>, columns: readonly RuleColumn<T>[]): string { const column = findColumn(columns, rule.column) const condition: RuleCondition = rule.when ?? { op: rule.op!, value: rule.value, values: rule.values } const name = columnName(column, rule.column) const word = RULE_OP_LABELS[condition.op] const text = (raw: RuleValue | undefined) => (raw === undefined || raw === null ? "" : String(raw)) if (condition.op === "isNull" || condition.op === "notNull") return `${name} ${word}` if (condition.op === "between") { const [lo, hi] = condition.values ?? [] return `${name} ${word} ${text(lo)} and ${text(hi)}` } if (condition.op === "in") return `${name} ${word} ${(condition.values ?? []).map(text).join(", ")}` return `${name} ${word} ${text(condition.value)}` } /** Every rule has to hold. A rule on a column the grid does not have is skipped, so a stale rule hides nothing. */ export function compileFilter<T>(rules: readonly FilterRule[], columns: readonly RuleColumn<T>[]): (row: T) => boolean { const tests: ((row: T) => boolean)[] = [] for (const rule of rules) { const column = findColumn(columns, rule.column) if (column) tests.push(compileCondition(rule, column)) } if (!tests.length) return () => true if (tests.length === 1) return tests[0]! return (row) => tests.every((test) => test(row)) } /** The first rule that tells two rows apart decides, nulls last either way. Undefined when no rule names a column the grid has. */ export function compileComparator<T>(rules: readonly SortRule[], columns: readonly RuleColumn<T>[]): ((a: T, b: T) => number) | undefined { const keys: { accessor: (row: T) => unknown; dir: "asc" | "desc" }[] = [] for (const rule of rules) { const column = findColumn(columns, rule.key) if (column) keys.push({ accessor: column.accessor, dir: rule.dir }) } if (!keys.length) return undefined return (a, b) => { for (const { accessor, dir } of keys) { const c = compareDirected(accessor(a), accessor(b), dir) if (c !== 0) return c } return 0 } } /** The decoration a matched rule puts on its cell or row. */ export function ruleDecoration<T>(rule: ColumnRule, columns: readonly RuleColumn<T>[]): RuleDecoration { return { "data-rule": rule.id, "data-tone": rule.tone, "aria-description": rule.label?.trim() || describeRule(rule, columns), className: RULE_TONE_CLASS[rule.tone], } } export interface AppliedRules<T> { /** The first cell rule on this column that the row matches, or undefined. */ cell: (columnKey: string, row: T) => RuleDecoration | undefined /** The first row rule the row matches, or undefined. Shaped for the grid's `getRowProps`. */ getRowProps: (row: T) => RuleDecoration | undefined /** The rules that name a column the grid has, by column key, in the order they apply. */ byColumn: ReadonlyMap<string, readonly ColumnRule[]> } /** * Column rules compiled once: each against its column, its decoration made ahead of time, and the * grid's two hooks, `cell` and `getRowProps`, answering per row with a matched rule's decoration. A * rule naming a column the grid does not have is skipped. */ export function applyRules<T>(rules: readonly ColumnRule[], columns: readonly RuleColumn<T>[]): AppliedRules<T> { const cells = new Map<string, { test: (row: T) => boolean; decoration: RuleDecoration }[]>() const rows: { test: (row: T) => boolean; decoration: RuleDecoration }[] = [] const byColumn = new Map<string, ColumnRule[]>() for (const rule of rules) { const column = findColumn(columns, rule.column) if (!column) continue const compiled = { test: compileCondition(rule.when, column), decoration: ruleDecoration(rule, columns) } byColumn.set(rule.column, [...(byColumn.get(rule.column) ?? []), rule]) if (rule.target === "row") rows.push(compiled) else cells.set(rule.column, [...(cells.get(rule.column) ?? []), compiled]) } return { cell(columnKey, row) { const list = cells.get(columnKey) if (!list) return undefined for (const { test, decoration } of list) if (test(row)) return decoration return undefined }, getRowProps(row) { for (const { test, decoration } of rows) if (test(row)) return decoration return undefined }, byColumn, } } -
Add the tokens to your stylesheet:
:root { --down: oklch(0.46 0.19 40); --down-soft: oklch(0.46 0.19 40 / 18%); --expiring: oklch(0.53 0.2 350); --expiring-soft: oklch(0.53 0.2 350 / 18%); --flat: var(--color-muted-foreground); --flat-soft: oklch(0.55 0 0 / 14%); --stale: oklch(0.52 0.13 75); --stale-soft: oklch(0.52 0.13 75 / 16%); --tradecn-font-accessible: 'Atkinson Hyperlegible Next', 'Atkinson Hyperlegible', ui-sans-serif, system-ui, sans-serif; --tradecn-font-accessible-mono: 'Atkinson Hyperlegible Mono', ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; --tradecn-font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; --tradecn-font-numeric: var(--tradecn-font-sans); --tradecn-font-sans: 'Inter', ui-sans-serif, system-ui, sans-serif; --up: oklch(0.52 0.13 165); --up-soft: oklch(0.52 0.13 165 / 18%); } .dark { --down: oklch(0.66 0.19 40); --down-soft: oklch(0.66 0.19 40 / 18%); --expiring: oklch(0.74 0.17 350); --expiring-soft: oklch(0.74 0.17 350 / 18%); --flat: var(--color-muted-foreground); --flat-soft: oklch(0.7 0 0 / 14%); --stale: oklch(0.8 0.15 80); --stale-soft: oklch(0.8 0.15 80 / 16%); --tradecn-font-accessible: 'Atkinson Hyperlegible Next', 'Atkinson Hyperlegible', ui-sans-serif, system-ui, sans-serif; --tradecn-font-accessible-mono: 'Atkinson Hyperlegible Mono', ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; --tradecn-font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; --tradecn-font-numeric: var(--tradecn-font-sans); --tradecn-font-sans: 'Inter', ui-sans-serif, system-ui, sans-serif; --up: oklch(0.74 0.15 165); --up-soft: oklch(0.74 0.15 165 / 18%); } -
Append this to your stylesheet:
:root[data-accessibility="hyperlegible"], [data-accessibility="hyperlegible"] { --tradecn-font-sans: var(--tradecn-font-accessible); --tradecn-font-mono: var(--tradecn-font-accessible-mono); }
Usage
import { useState } from "react"
import { createRowStore } from "@/lib/row-store"
import { Positions, type PositionRow } from "@/components/ui/positions"
const rows: PositionRow[] = [
{ id: "T2", book: "Cash", instrument: "T 2Y", position: 50_000_000, average: 100.25, mark: 100.28125, dayPnl: 15_625, totalPnl: 62_000, risk: 21_500 },
{ id: "T10", book: "Cash", instrument: "T 10Y", position: -25_000_000, average: 99.5, mark: 99.515625, dayPnl: -3_906, totalPnl: -12_000, risk: -21_000 },
{ id: "T30", book: "Cash", instrument: "T 30Y", position: 0, average: null, mark: 98.75, dayPnl: 0, totalPnl: null, risk: null },
]
function CashPositions() {
const [store] = useState(() => {
const store = createRowStore<PositionRow>({ getRowId: (row) => row.id })
store.applyDeltas({ upsert: rows })
return store
})
return <div className="h-48 w-fit max-w-full"><Positions store={store} label="Cash positions" riskHeader="DV01" /></div>
}
The three rows show long, short and flat positions in one book. Without quantityUnit, quantities print as notional amounts in millions. Missing optional values use –. The footer counts the positions and sums their supplied P&L and risk, omitting missing values; it does not sum quantities across instruments.
Every value is a fixed server snapshot. The grid displays these numbers and totals them; it does not calculate P&L from average prices, marks or quantities.
Formats and units
Set quantityUnit="contracts" for a contract count and leave it omitted for notional amounts. This example prints TY as +120 and the cash position as −25mm. A stable price callback chooses fractional prices for T 10Y and three decimal places for TY. The shared money formatter prints compact P&L and DV01 for both cells and totals; it retains negative signs.
import { useState } from "react"
import { createInstrumentFormatter, formatDv01 } from "@/lib/format"
import { createRowStore } from "@/lib/row-store"
import { Positions, type PositionRow } from "@/components/ui/positions"
const note = createInstrumentFormatter({ price: { kind: "fraction", denominator: 32, half: "+" }, tick: 1 / 64 })
const price = (value: number, row: PositionRow) => row.instrument === "T 10Y" ? note.price(value) : value.toFixed(3)
const money = (value: number) => formatDv01(value, { compact: true })
export default function PositionsFormatsDemo() {
const [store] = useState(() => {
const store = createRowStore<PositionRow>({ getRowId: (row) => row.id })
store.applyDeltas({ upsert: [
{ id: "TY", book: "Rates", instrument: "TY", position: 120, quantityUnit: "contracts", average: 110.281, mark: 110.5, dayPnl: 26_250, totalPnl: 41_000, risk: 8_400 },
{ id: "T10", book: "Rates", instrument: "T 10Y", position: -25_000_000, average: 99.5, mark: 99.515625, dayPnl: -3_906, totalPnl: -12_000, risk: -21_000 },
] })
return store
})
return <div className="h-40 w-fit max-w-full"><Positions store={store} label="Formatted rates positions" riskHeader="DV01" price={price} pnl={money} risk={money} /></div>
}
Separate books
Give each book its own store and named grid to keep selection, sorting and totals separate. These two books each contain one position, so each footer belongs only to that book. Book seeds its store once from its initial rows; subsequent data belongs in store batches.
import { useState } from "react"
import { createRowStore } from "@/lib/row-store"
import { Positions, type PositionRow } from "@/components/ui/positions"
const futures: PositionRow[] = [
{ id: "TY", book: "Futures", instrument: "TY", position: 120, quantityUnit: "contracts", average: 110.25, mark: 110.5, dayPnl: 26_250, totalPnl: 41_000, risk: 8_400 },
]
const cash: PositionRow[] = [
{ id: "T10", book: "Cash", instrument: "T 10Y", position: -25_000_000, average: 99.5, mark: 99.515625, dayPnl: -3_906, totalPnl: -12_000, risk: -21_000 },
]
function Book({ name, rows }: { name: string; rows: PositionRow[] }) {
const [store] = useState(() => {
const store = createRowStore<PositionRow>({ getRowId: (row) => row.id })
store.applyDeltas({ upsert: rows })
return store
})
return (
<section aria-label={`${name} book`} className="space-y-1">
<h3 className="text-xs font-semibold">{name}</h3>
<div className="h-32"><Positions store={store} label={`${name} positions`} riskHeader="DV01" /></div>
</section>
)
}
export default function PositionsBooksDemo() {
return <div className="w-fit max-w-full space-y-4"><Book name="Futures" rows={futures} /><Book name="Cash" rows={cash} /></div>
}
Server updates
The Apply next server batch button first changes only the cash note's mark. P&L and risk stay unchanged. The second batch supplies new P&L and risk values; those cells and their totals update. Changed cells flash, while totals do not. The sample values are explicit server outputs, not a valuation model.
The final state stays visible until Restore book replaces the original rows. Selection, sorting and column settings stay as you left them. There is no background publisher. Scroll the grid horizontally on a narrow screen to inspect the mark, P&L and risk columns.
import { useState } from "react"
import { createRowStore, type DeltaBatch } from "@/lib/row-store"
import { Positions, type PositionRow } from "@/components/ui/positions"
const rows: PositionRow[] = [
{ id: "T2", book: "Cash", instrument: "T 2Y", position: 50_000_000, average: 100.25, mark: 100.28125, dayPnl: 15_625, totalPnl: 62_000, risk: 21_500 },
{ id: "T10", book: "Cash", instrument: "T 10Y", position: -25_000_000, average: 99.5, mark: 99.515625, dayPnl: -3_906, totalPnl: -12_000, risk: -21_000 },
]
const updates: { message: string; batch: DeltaBatch<PositionRow> }[] = [
{ message: "Mark updated; P&L and risk unchanged.", batch: { patch: [{ id: "T10", fields: { mark: 99.53125 } }] } },
{ message: "Server P&L and risk applied.", batch: { patch: [{ id: "T10", fields: { dayPnl: -3_000, totalPnl: -11_000, risk: -20_500 } }] } },
]
export default function PositionsUpdatesDemo() {
const [store] = useState(() => {
const store = createRowStore<PositionRow>({ getRowId: (row) => row.id })
store.applyDeltas({ upsert: rows })
return store
})
const [step, setStep] = useState(0)
const advance = () => {
const update = updates[step]
if (!update) return
store.applyDeltas(update.batch)
setStep(step + 1)
}
const restore = () => {
store.applyDeltas({ upsert: rows })
setStep(0)
}
return (
<>
<div data-demo-controls className="flex flex-wrap gap-2 text-xs">
<button type="button" className="rounded border px-2 py-1 disabled:opacity-50" disabled={step === updates.length} onClick={advance}>Apply next server batch</button>
<button type="button" className="rounded border px-2 py-1" onClick={restore}>Restore book</button>
</div>
<div className="w-fit max-w-full space-y-2 text-xs lining-nums tabular-nums">
<div className="h-40"><Positions store={store} label="Updated cash positions" riskHeader="DV01" /></div>
<p role="status" className="text-muted-foreground">{updates[step - 1]?.message ?? "Initial book."}</p>
</div>
</>
)
}
API Reference
Positions uses data-grid's blotter preset: 24 px rows, fill flashes, arrival highlights, and viewport pinning when rows arrive above the visible area. Selection defaults to single with no checkboxes. Shared files are byte-identical to those installed by data-grid, watchlist, and blotter.
Props
PositionsProps<T> accepts rows extending PositionRow. Give the grid a container with a height.
| Prop | Type | Default | Purpose |
|---|---|---|---|
store |
RowStore<T> |
Required | Position rows. |
columns |
ColumnDef<T>[] |
positionsColumns(options) |
Replace or extend the book's columns. |
price |
(value: number, row: T) => string |
Two decimals | Format average and mark prices by instrument. |
pnl |
(value: number, row: T) => string |
Signed whole number with separators | Format both P&L columns and their default totals. |
risk |
(value: number, row: T) => string |
Signed whole number with separators | Format risk cells and the default risk total. |
riskHeader |
string |
"Risk" |
Name the default risk column, such as DV01 or Delta. |
totals |
false | Record<string, (rows: T[]) => string> |
positionsTotals(options) |
Replace the footer values by column key, or hide the footer. |
label |
string |
"Positions" |
Accessible name of the grid. |
selectionMode |
"none" | "single" | "multi" |
"single" |
Choose selection behavior. |
selectionColumn |
boolean |
false |
Show checkboxes when selection is "multi". |
renderContextMenu |
(rows: T[], ids: RowId[]) => ReactNode |
None | Menu items for the selection or targeted row. |
getRowProps |
(row: T, id: RowId) => RowDecoration | undefined |
Side decorations | Add row classes or override the side's state and accessible description. |
className |
string |
None | Classes on the outer Positions container. |
Sorting, filtering, a supplied view, column state, row callbacks, and keyboard behavior follow DataGrid. preset and footer are excluded; use totals for the footer. PositionsColumnOptions<T> is the shared options type for price, pnl, risk, and riskHeader.
Every number is the server's
The server supplies positions, prices, P&L, and risk. The grid displays them and adds totals; it does not calculate P&L from positions and marks. Fills, funding, and corrections belong to the server.
PositionRow field |
Type | Meaning |
|---|---|---|
id |
string |
Position ID; the example uses it as the store's row key. |
instrument |
string |
Instrument name or identifier. |
position |
number |
Signed notional amount or contract count: positive is long, negative is short, zero is flat. |
quantityUnit |
"notional" | "contracts", optional |
Defaults to notional, displayed in millions: -25_000_000 becomes −25mm. Contracts display as a whole count, such as +120. |
book |
string, optional |
Book name. |
average, mark |
number | null, optional |
Average price and current mark, printed through price. |
dayPnl, totalPnl |
number | null, optional |
P&L in the account's currency, printed through pnl. |
risk |
number | null, optional |
The desk's risk measure, such as DV01, delta, or beta-weighted exposure. |
Missing optional cell values print the null token. formatPosition also returns it for a non-finite position.
The sign says which way
Default position, P&L, and risk cells use up for positive finite values, down for negative finite values, and flat for zero. Position text uses signed quantities such as +120 and −25mm.
P&L and risk round to whole numbers by default. A small negative value such as -0.1 prints 0, while 0.1 prints +0; the color still follows the unrounded value. Supply a formatter with enough precision when those small values need to remain distinguishable without color. Zero itself prints without a sign.
The position span carries data-side="long", "short", or "flat". The row defaults to the same data-state, with an aria-description of long or short; flat rows have no default description. Your getRowProps can override either row attribute.
| Helper | Behavior |
|---|---|
formatPosition(row) |
Format a signed notional amount in millions or a whole contract count. |
positionSide(position) |
Return "long", "short", or "flat" from the position's sign. |
withSign(value, text) |
Prefix positive values with + unless the text already starts with +, −, or -. Used for P&L and risk cells and default totals. |
Custom pnl and risk formatters must retain negative signs themselves; withSign only adds a missing positive sign.
Columns
positionsColumns({ price, pnl, risk, riskHeader }) returns definitions in this order: book, instrument, position, average, mark, day P&L, total P&L, and risk. Instrument is frozen on the left; the grid places frozen columns before the others. Spread the list to add, remove, or reorder columns.
Position, mark, both P&Ls, and risk flash on value changes. Book, instrument, and average have flashing disabled. Override a column's flash setting in a custom list to change that behavior.
Keep columns and the formatters stable with module constants or memoization. Formatters receive the current row for cells; totals use the calling convention below. Supplying columns replaces the default definitions, so their cell formatting and riskHeader are then yours to set.
Totals
positionsTotals(options) produces the default footer values:
| Column key | Total |
|---|---|
instrument |
Row count, such as 3 positions. |
dayPnl, totalPnl |
Sum of finite numeric values, through pnl. |
risk |
Sum of finite numeric values, through risk. |
Totals read all rows in the grid's current view, including those outside the viewport. They update on store batches and when the view or footer inputs change. Null, missing, and non-finite values are omitted from sums; a sum with no finite values prints the null token. Totals do not flash. There is no position total because instruments can have different units.
The default total formatters receive (sum, rows[0]): the second argument is the first row in the current view, even if that row has no value for the summed field. It does not describe the aggregate. Use formatters appropriate to the whole book, or supply totals when aggregation needs more context.
Custom totals replaces the default map. Each function receives the view's rows in order and returns display text for its column key; only visible columns render totals. totals={false} hides the footer.
One grid per book
For several books, render one Positions per book with a separate store or filtered view and its own totals, as the separate-books example does. The grid has fixed-height rows for viewport pinning and does not group or nest positions.
What it does not do
It does not fetch, price, or net positions, or derive a position from fills. Use renderContextMenu or onRowActivate to open your ticket for a hedge, close, or transfer.
Tokens
The install adds the grid's up, down, flat, stale, and expiring tokens and their soft variants where missing. Positive, negative, and flat cells use the first three.
Built on shadcn's checkbox, context-menu, and dropdown-menu.
This page is docs/positions.md at v1.4.13.