feat(admin): shift-select multiple sessions in process list

apps/desktop/src/lib/__tests__/database/processListSelection.spec.ts

@@ -0,0 +1,51 @@
+import { describe, expect, it } from "vitest";
+import { processListSelectionAfterClick, type ProcessListSelectionState } from "@/lib/database/processListSelection";
+
+const rows = [{ id: 11 }, { id: 12 }, { id: 13 }, { id: 14 }, { id: 15 }];
+const plain = { shiftKey: false, metaKey: false, ctrlKey: false };
+const shift = { shiftKey: true, metaKey: false, ctrlKey: false };
+const ctrl = { shiftKey: false, metaKey: false, ctrlKey: true };
+
+function state(selected: number[], anchorId: number | null): ProcessListSelectionState {
+  return { selected: new Set(selected), anchorId };
+}
+
+describe("processListSelectionAfterClick", () => {
+  it("toggles one row and moves the anchor on a plain click", () => {
+    expect(processListSelectionAfterClick(rows, state([], null), 12, plain)).toEqual({ selected: new Set([12]), anchorId: 12 });
+    expect(processListSelectionAfterClick(rows, state([12, 14], 12), 14, plain)).toEqual({ selected: new Set([12]), anchorId: 14 });
+  });
+
+  it("selects the whole range on Shift+click in either direction", () => {
+    expect(processListSelectionAfterClick(rows, state([12], 12), 15, shift)).toEqual({ selected: new Set([12, 13, 14, 15]), anchorId: 12 });
+    expect(processListSelectionAfterClick(rows, state([15], 15), 12, shift)).toEqual({ selected: new Set([12, 13, 14, 15]), anchorId: 15 });
+  });
+
+  it("deselects the range when the Shift+clicked row was already selected", () => {
+    expect(processListSelectionAfterClick(rows, state([12, 13, 14, 15], 12), 14, shift)).toEqual({ selected: new Set([15]), anchorId: 12 });
+  });
+
+  it("keeps the anchor so consecutive Shift+clicks re-extend from the same row", () => {
+    const first = processListSelectionAfterClick(rows, state([12], 12), 14, shift);
+    expect(processListSelectionAfterClick(rows, first, 15, shift)).toEqual({ selected: new Set([12, 13, 14, 15]), anchorId: 12 });
+  });
+
+  it("keeps rows outside the range untouched", () => {
+    expect(processListSelectionAfterClick(rows, state([11, 12, 15], 12), 13, shift)).toEqual({ selected: new Set([11, 12, 13, 15]), anchorId: 12 });
+  });
+
+  it("treats Cmd/Ctrl as a single toggle", () => {
+    expect(processListSelectionAfterClick(rows, state([12], 12), 14, ctrl)).toEqual({ selected: new Set([12, 14]), anchorId: 14 });
+  });
+
+  it("falls back to a plain toggle when the Shift anchor is gone", () => {
+    expect(processListSelectionAfterClick(rows, state([12], 99), 13, shift)).toEqual({ selected: new Set([12, 13]), anchorId: 13 });
+    expect(processListSelectionAfterClick(rows, state([12], null), 13, shift)).toEqual({ selected: new Set([12, 13]), anchorId: 13 });
+  });
+
+  it("ignores ids that are not selectable in the current list", () => {
+    const current = state([12], 12);
+    expect(processListSelectionAfterClick(rows, current, 99, plain)).toBe(current);
+    expect(processListSelectionAfterClick(rows, current, 99, shift)).toBe(current);
+  });
+});

apps/desktop/src/lib/__tests__/selection/orderedListSelection.spec.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { orderedListRangeAnchorIndex, orderedListSelectionIntent } from "@/lib/selection/orderedListSelection";
+import { orderedListRangeAnchorIndex, orderedListRangeIndices, orderedListSelectionIntent } from "@/lib/selection/orderedListSelection";
 
 describe("orderedListSelectionIntent", () => {
   it("uses Shift for range selection even when another modifier is also reported", () => {
@@ -38,3 +38,21 @@ describe("orderedListRangeAnchorIndex", () => {
     expect(orderedListRangeAnchorIndex(items, null, { type: "file", id: "missing" })).toBeNull();
   });
 });
+
+describe("orderedListRangeIndices", () => {
+  it("covers both directions inclusively", () => {
+    expect(orderedListRangeIndices(5, 1, 3)).toEqual([1, 2, 3]);
+    expect(orderedListRangeIndices(5, 3, 1)).toEqual([1, 2, 3]);
+    expect(orderedListRangeIndices(5, 2, 2)).toEqual([2]);
+  });
+
+  it("clamps to the list bounds", () => {
+    expect(orderedListRangeIndices(3, 0, 2)).toEqual([0, 1, 2]);
+  });
+
+  it("returns nothing for an empty list or an out-of-range position", () => {
+    expect(orderedListRangeIndices(0, 0, 0)).toEqual([]);
+    expect(orderedListRangeIndices(3, -1, 1)).toEqual([]);
+    expect(orderedListRangeIndices(3, 1, 3)).toEqual([]);
+  });
+});

apps/desktop/src/lib/database/processListSelection.ts

@@ -0,0 +1,44 @@
+import { orderedListRangeIndices, orderedListSelectionIntent } from "../selection/orderedListSelection";
+
+/** Rows are identified by the server session id, matching the process list grid. */
+export interface ProcessListSelectionRow {
+  id: number;
+}
+
+export interface ProcessListSelectionState {
+  selected: Set<number>;
+  anchorId: number | null;
+}
+
+/**
+ * Applies a row checkbox click to the current selection.
+ *
+ * A plain click toggles the clicked row and moves the anchor; Shift+click applies
+ * the clicked row's next state to every selectable row between the anchor and the
+ * clicked row, so long session lists can be selected in one gesture. Rows outside
+ * the range keep their current state, and an unknown/stale anchor degrades to a
+ * plain toggle instead of selecting an unexpected range.
+ *
+ * The next state is derived from the current selection because the grid binds
+ * `:checked` without cancelling the native checkbox activation.
+ */
+export function processListSelectionAfterClick(rows: ProcessListSelectionRow[], state: ProcessListSelectionState, id: number, event: Pick<MouseEvent, "shiftKey" | "metaKey" | "ctrlKey">): ProcessListSelectionState {
+  const targetIndex = rows.findIndex((row) => row.id === id);
+  if (targetIndex < 0) return state;
+  const checked = !state.selected.has(id);
+  const anchorIndex = state.anchorId === null ? -1 : rows.findIndex((row) => row.id === state.anchorId);
+  if (orderedListSelectionIntent(event) === "range" && anchorIndex >= 0) {
+    const selected = new Set(state.selected);
+    for (const index of orderedListRangeIndices(rows.length, anchorIndex, targetIndex)) {
+      const row = rows[index];
+      if (!row) continue;
+      if (checked) selected.add(row.id);
+      else selected.delete(row.id);
+    }
+    return { selected, anchorId: state.anchorId };
+  }
+  const selected = new Set(state.selected);
+  if (checked) selected.add(id);
+  else selected.delete(id);
+  return { selected, anchorId: id };
+}

apps/desktop/src/lib/selection/orderedListSelection.ts

@@ -17,3 +17,12 @@ export function orderedListRangeAnchorIndex(items: OrderedListSelectionItem[], a
   const index = items.findIndex((item) => item.type === activeItem.type && item.id === activeItem.id);
   return index >= 0 ? index : null;
 }
+
+/** Inclusive, clamped index range between two positions in an ordered list. */
+export function orderedListRangeIndices(length: number, anchorIndex: number, focusIndex: number): number[] {
+  if (length <= 0) return [];
+  if (anchorIndex < 0 || anchorIndex >= length || focusIndex < 0 || focusIndex >= length) return [];
+  const start = Math.min(anchorIndex, focusIndex);
+  const end = Math.max(anchorIndex, focusIndex);
+  return Array.from({ length: end - start + 1 }, (_, offset) => start + offset);
+}