import { describe, expect, it } from "vite-plus/test"; import {  createComposerScrollGestureState,  recordComposerScrollGestureEvent,  resetComposerScrollGesture,  shouldCollapseComposerForScrollKey,  suppressActiveComposerScrollGesture,} from "./composerScrollGesture"; const RESET_MS = 120;const THRESHOLD_PX = 24; describe("composer keyboard scroll collapse", () => {  const middle = {    scrollTop: 500,    scrollHeight: 1500,    clientHeight: 500,    isAtLogicalEnd: false,  };   it.each(["PageUp", "PageDown", "Home", "End"])("collapses on %s in the timeline", (key) => {    expect(shouldCollapseComposerForScrollKey({ ...middle, key })).toBe(true);  });   it.each(["PageUp", "Home"])("does not collapse on %s at the top", (key) => {    expect(shouldCollapseComposerForScrollKey({ ...middle, key, scrollTop: 0 })).toBe(false);  });   it.each(["PageDown", "End"])("does not collapse on %s at the logical end", (key) => {    expect(shouldCollapseComposerForScrollKey({ ...middle, key, isAtLogicalEnd: true })).toBe(      false,    );    expect(shouldCollapseComposerForScrollKey({ ...middle, key, scrollTop: 1000 })).toBe(false);  });   it("ignores unrelated keys", () => {    expect(shouldCollapseComposerForScrollKey({ ...middle, key: "Enter" })).toBe(false);  });}); function record(  state: ReturnType<typeof createComposerScrollGestureState>,  now: number,  options: Partial<{    deltaPx: number;    collapseEligible: boolean;    canScrollInGestureDirection: boolean;    scrollsTowardLogicalEnd: boolean;  }> = {},) {  return recordComposerScrollGestureEvent(state, {    now,    deltaPx: options.deltaPx ?? 30,    collapseThresholdPx: THRESHOLD_PX,    collapseEligible: options.collapseEligible ?? true,    canScrollInGestureDirection: options.canScrollInGestureDirection ?? true,    scrollsTowardLogicalEnd: options.scrollsTowardLogicalEnd ?? false,  });} describe("composer scroll gesture", () => {  it("lets an editor change win over the rest of the active gesture", () => {    const state = createComposerScrollGestureState();     expect(record(state, 0)).toBe(true);    suppressActiveComposerScrollGesture(state, 20, RESET_MS);     expect(record(state, 40)).toBe(false);    expect(record(state, 80)).toBe(false);    expect(record(state, 160)).toBe(false);  });   it("preserves suppression while collapse is temporarily ineligible", () => {    const state = createComposerScrollGestureState();     record(state, 0);    suppressActiveComposerScrollGesture(state, 20, RESET_MS);     expect(record(state, 40, { collapseEligible: false })).toBe(false);    expect(record(state, 80, { collapseEligible: true })).toBe(false);  });   it("keeps a boundary momentum tail in the same suppressed gesture", () => {    const state = createComposerScrollGestureState();     record(state, 0);    suppressActiveComposerScrollGesture(state, 20, RESET_MS);     expect(record(state, 80, { canScrollInGestureDirection: false })).toBe(false);    expect(state.lastEventAt).toBe(80);    expect(record(state, 160)).toBe(false);  });   it("does not carry gesture state into a new thread after reset", () => {    const state = createComposerScrollGestureState();     record(state, 0);    suppressActiveComposerScrollGesture(state, 20, RESET_MS);    record(state, 80);    resetComposerScrollGesture(state);     expect(record(state, 240)).toBe(true);  });   it("accumulates small deltas only while collapse remains eligible and scrollable", () => {    const state = createComposerScrollGestureState();     expect(record(state, 0, { deltaPx: 10 })).toBe(false);    expect(record(state, 20, { deltaPx: 10 })).toBe(false);    expect(record(state, 40, { deltaPx: 4 })).toBe(true);    expect(record(state, 60, { deltaPx: 10, collapseEligible: false })).toBe(false);    expect(record(state, 80, { deltaPx: 14 })).toBe(false);  });   it("does not collapse while scrolling down through composer footer space", () => {    const state = createComposerScrollGestureState();     expect(record(state, 0, { deltaPx: 20 })).toBe(false);    expect(record(state, 20, { scrollsTowardLogicalEnd: true })).toBe(false);    expect(record(state, 40, { deltaPx: 10 })).toBe(false);  });});