feat: table enhancement (#2191)

2026-05-20 16:44:05 +08:00 · 2026-05-14 00:37:44 +01:00
parent 31ed0df3f7
commit cea9be7926
48 changed files with 3330 additions and 1133 deletions
@@ -0,0 +1,186 @@
+// Per-table header-pin controller: native sticky when table fits its wrapper, transform fallback when it doesn't.
+
+import { computePinTop, pinOffsetWatcher } from './offset';
+
+const WRAPPER_NO_OVERFLOW = 'tableWrapperNoOverflow';
+const HEADER_PINNED = 'tableHeaderPinned';
+const PIN_OFFSET_VAR = '--table-pin-offset';
+
+type PinMode = 'off' | 'native' | 'fallback';
+
+function firstRowIsAllHeaders(row: HTMLTableRowElement | null): boolean {
+  if (!row) return false;
+  const cells = Array.from(row.cells);
+  return cells.length > 0 && cells.every((c) => c.tagName === 'TH');
+}
+
+function isNestedTable(wrapper: HTMLElement): boolean {
+  return wrapper.closest('table .tableWrapper') !== null;
+}
+
+function isLayoutInert(rect: DOMRectReadOnly): boolean {
+  return rect.width === 0 && rect.height === 0;
+}
+
+const fallbackControllers = new Set<TablePinController>();
+let fallbackScrollListener: (() => void) | null = null;
+let fallbackRafPending = false;
+
+function ensureFallbackListener() {
+  if (fallbackScrollListener) return;
+  fallbackScrollListener = () => {
+    if (fallbackRafPending) return;
+    fallbackRafPending = true;
+    requestAnimationFrame(() => {
+      fallbackRafPending = false;
+      for (const ctrl of fallbackControllers) ctrl.updateFallbackOffset();
+    });
+  };
+  document.addEventListener('scroll', fallbackScrollListener, {
+    passive: true,
+    capture: true,
+  });
+}
+
+function maybeTeardownFallbackListener() {
+  if (!fallbackScrollListener || fallbackControllers.size > 0) return;
+  document.removeEventListener('scroll', fallbackScrollListener, {
+    capture: true,
+  });
+  fallbackScrollListener = null;
+  fallbackRafPending = false;
+}
+
+export class TablePinController {
+  private wrapper: HTMLElement;
+  private table: HTMLTableElement;
+  private fitsObserver?: IntersectionObserver;
+  private mode: PinMode = 'off';
+  private cachedHeaderRow: HTMLTableRowElement | null = null;
+
+  constructor(wrapper: HTMLElement, table: HTMLTableElement) {
+    this.wrapper = wrapper;
+    this.table = table;
+    pinOffsetWatcher.acquire();
+    this.fitsObserver = new IntersectionObserver(
+      (entries) => {
+        for (const entry of entries) this.evaluateFit(entry);
+      },
+      { root: this.wrapper, threshold: 1 },
+    );
+    this.fitsObserver.observe(this.table);
+  }
+
+  private getHeaderRow(): HTMLTableRowElement | null {
+    if (this.cachedHeaderRow && this.table.contains(this.cachedHeaderRow)) {
+      return this.cachedHeaderRow;
+    }
+    this.cachedHeaderRow = this.table.querySelector('tr');
+    return this.cachedHeaderRow;
+  }
+
+  private evaluateFit(entry: IntersectionObserverEntry) {
+    if (!this.isEligible()) {
+      this.apply('off');
+      return;
+    }
+    if (isLayoutInert(entry.boundingClientRect)) return;
+    this.apply(entry.isIntersecting ? 'native' : 'fallback');
+  }
+
+  private isEligible(): boolean {
+    return (
+      !isNestedTable(this.wrapper) && firstRowIsAllHeaders(this.getHeaderRow())
+    );
+  }
+
+  private apply(next: PinMode) {
+    if (next === this.mode) return;
+
+    if (this.mode === 'fallback' && next !== 'fallback') {
+      fallbackControllers.delete(this);
+      maybeTeardownFallbackListener();
+    }
+
+    this.mode = next;
+    const cls = this.wrapper.classList;
+
+    if (next === 'off') {
+      cls.remove(HEADER_PINNED);
+      cls.remove(WRAPPER_NO_OVERFLOW);
+      this.wrapper.style.removeProperty(PIN_OFFSET_VAR);
+    } else if (next === 'native') {
+      cls.add(HEADER_PINNED);
+      cls.add(WRAPPER_NO_OVERFLOW);
+      // Native mode reads --editor-pin-offset from :root; clear stale per-wrapper var from fallback.
+      this.wrapper.style.removeProperty(PIN_OFFSET_VAR);
+    } else if (next === 'fallback') {
+      cls.add(HEADER_PINNED);
+      cls.remove(WRAPPER_NO_OVERFLOW);
+      fallbackControllers.add(this);
+      ensureFallbackListener();
+      // Avoid one stale-frame paint under translateY.
+      this.updateFallbackOffset();
+    }
+  }
+
+  updateFallbackOffset() {
+    const pinTop = computePinTop();
+    const tableRect = this.table.getBoundingClientRect();
+    const headerRow = this.getHeaderRow();
+    if (!headerRow) return;
+    const rowHeight = headerRow.getBoundingClientRect().height;
+
+    const active = tableRect.top < pinTop && tableRect.bottom > pinTop + rowHeight;
+
+    if (active) {
+      const offset = Math.min(pinTop - tableRect.top, tableRect.height - rowHeight);
+      this.wrapper.style.setProperty(PIN_OFFSET_VAR, `${offset}px`);
+    } else {
+      this.wrapper.style.removeProperty(PIN_OFFSET_VAR);
+    }
+  }
+
+  refresh() {
+    // The header <tr> may have been replaced by a PM transaction; drop
+    // the cached reference before checking eligibility.
+    this.cachedHeaderRow = null;
+    if (!this.isEligible()) {
+      this.apply('off');
+      return;
+    }
+    if (this.mode === 'off') {
+      // Eligibility just flipped back on; re-trigger the observer so it
+      // emits the current intersection state.
+      this.fitsObserver?.unobserve(this.table);
+      this.fitsObserver?.observe(this.table);
+    }
+  }
+
+  destroy() {
+    this.fitsObserver?.disconnect();
+    this.fitsObserver = undefined;
+    this.apply('off');
+    pinOffsetWatcher.release();
+  }
+}
+
+const controllers = new WeakMap<HTMLElement, TablePinController>();
+
+export function attach(wrapper: HTMLElement) {
+  if (controllers.has(wrapper)) return;
+  const table = wrapper.querySelector(':scope > table') as HTMLTableElement | null;
+  if (!table) return;
+  controllers.set(wrapper, new TablePinController(wrapper, table));
+}
+
+export function detach(wrapper: HTMLElement) {
+  const ctrl = controllers.get(wrapper);
+  if (!ctrl) return;
+  ctrl.destroy();
+  controllers.delete(wrapper);
+}
+
+export function getController(wrapper: HTMLElement): TablePinController | undefined {
+  return controllers.get(wrapper);
+}