Keep search, facets, and sort in the page URL.

CONTENT-WP-0002-T04 writes q, facet values, and sort into history so back and forward restore the table.

Assistant: grok
Assistant-Session: 01a1346c-fdff-7741-b1af-b7283661554b

ui/lib/table-view.ts

@@ -0,0 +1,113 @@
+/*
+ * URL shape adapted from OnCo viewParams: `q` for search, repeated facet keys,
+ * and `sort` with a leading "-" for descending.
+ * https://github.com/judegomila/OnCo @ b594d7433bf4e408b44215e25e5304696d6f840e
+ * Copyright (c) 2026 OnCo. MIT License. See ui/NOTICE.
+ *
+ * The compact `v` parameter, table scopes, and domain value normalisers are not included.
+ */
+
+import { cellSortValue, type BrowserRow } from "./browser-row";
+import { sortRows } from "./sort-rows";
+import type { SortState } from "./types";
+
+export type TableView = {
+  q: string;
+  facets: Record<string, string[]>;
+  sort?: SortState;
+};
+
+export type ViewHistory = {
+  read: () => string;
+  push: (search: string) => void;
+  subscribe: (listener: () => void) => () => void;
+};
+
+export function browserViewHistory(): ViewHistory {
+  return {
+    read: () => (typeof window === "undefined" ? "" : window.location.search),
+    push: (search) => {
+      const path = window.location.pathname;
+      window.history.pushState(null, "", search ? `${path}?${search}` : path);
+    },
+    subscribe: (listener) => {
+      window.addEventListener("popstate", listener);
+      return () => window.removeEventListener("popstate", listener);
+    },
+  };
+}
+
+export function facetKeysOf(rows: readonly BrowserRow[]): string[] {
+  const keys = new Set<string>();
+  for (const row of rows) {
+    for (const key of Object.keys(row.facets)) keys.add(key);
+  }
+  return [...keys].sort();
+}
+
+export function facetValues(rows: readonly BrowserRow[], key: string): string[] {
+  const values = new Set<string>();
+  for (const row of rows) {
+    for (const value of row.facets[key] ?? []) values.add(value);
+  }
+  return [...values].sort((a, b) => a.localeCompare(b));
+}
+
+function splitValues(params: URLSearchParams, key: string): string[] {
+  const values: string[] = [];
+  for (const raw of params.getAll(key)) {
+    for (const part of raw.split(",")) {
+      const trimmed = part.trim();
+      if (trimmed && !values.includes(trimmed)) values.push(trimmed);
+    }
+  }
+  return values;
+}
+
+export function parseTableView(
+  search: string,
+  facetKeys: readonly string[],
+  sortable: (key: string) => boolean,
+): TableView {
+  const params = new URLSearchParams(search.startsWith("?") ? search.slice(1) : search);
+  const facets: Record<string, string[]> = {};
+  for (const key of facetKeys) {
+    const values = splitValues(params, key);
+    if (values.length > 0) facets[key] = values;
+  }
+  const rawSort = params.get("sort");
+  let sort: SortState | undefined;
+  if (rawSort) {
+    const key = rawSort.replace(/^-/, "");
+    if (sortable(key)) sort = { key, dir: rawSort.startsWith("-") ? -1 : 1 };
+  }
+  return { q: params.get("q") ?? "", facets, sort };
+}
+
+export function serializeTableView(view: TableView, baseSort: SortState): string {
+  const params = new URLSearchParams();
+  for (const key of Object.keys(view.facets).sort()) {
+    for (const value of view.facets[key] ?? []) params.append(key, value);
+  }
+  const q = view.q.trim();
+  if (q) params.set("q", q);
+  if (view.sort && (view.sort.key !== baseSort.key || view.sort.dir !== baseSort.dir)) {
+    params.set("sort", `${view.sort.dir === -1 ? "-" : ""}${view.sort.key}`);
+  }
+  return params.toString();
+}
+
+export function applyTableView(rows: readonly BrowserRow[], view: TableView): BrowserRow[] {
+  const q = view.q.trim().toLowerCase();
+  const filtered = rows.filter((row) => {
+    for (const [key, selected] of Object.entries(view.facets)) {
+      if (selected.length === 0) continue;
+      const have = new Set(row.facets[key] ?? []);
+      if (!selected.some((value) => have.has(value))) return false;
+    }
+    if (!q) return true;
+    const haystack = [row.name, row.tldr, ...Object.values(row.facets).flat()].join("\n").toLowerCase();
+    return haystack.includes(q);
+  });
+  return sortRows(filtered, view.sort, cellSortValue);
+}