import assert from "node:assert/strict";
import { readFile } from "node:fs/promises";

const helperUrl = new URL("../src/utils/discoveryPanelScroll.js", import.meta.url);
const chatMainListUrl = new URL("../src/pages/ChatMain/ChatMainList/index.vue", import.meta.url);
const helperSource = await readFile(helperUrl, "utf8");
const chatMainListSource = await readFile(chatMainListUrl, "utf8");
const helperModule = await import(
  `data:text/javascript;charset=utf-8,${encodeURIComponent(helperSource)}`
);

const {
  canExpandDiscoveryPanelFromScroll,
  getDiscoveryPanelCollapseState,
} = helperModule;

assert.equal(
  getDiscoveryPanelCollapseState({
    currentScrollTop: 24,
    lastScrollTop: 0,
    isCollapsed: false,
    threshold: 16,
  }),
  true,
  "scrolling up into discovery content should collapse the welcome panel"
);

assert.equal(
  getDiscoveryPanelCollapseState({
    currentScrollTop: 18,
    lastScrollTop: 15,
    isCollapsed: false,
    threshold: 16,
  }),
  true,
  "slow upward scrolling past the threshold should collapse the welcome panel"
);

assert.equal(
  getDiscoveryPanelCollapseState({
    currentScrollTop: 40,
    lastScrollTop: 64,
    isCollapsed: true,
    threshold: 16,
    allowExpand: true,
  }),
  false,
  "scrolling down should reveal the welcome panel"
);

assert.equal(
  getDiscoveryPanelCollapseState({
    currentScrollTop: 40,
    lastScrollTop: 64,
    isCollapsed: true,
    threshold: 16,
    allowExpand: false,
  }),
  true,
  "layout-driven reverse scroll after release should not reveal the welcome panel"
);

assert.equal(
  getDiscoveryPanelCollapseState({
    currentScrollTop: 63,
    lastScrollTop: 64,
    isCollapsed: true,
    threshold: 16,
  }),
  true,
  "small scroll jitter should keep the current panel state"
);

assert.match(
  chatMainListSource,
  /@touchmove\.capture="handleDiscoveryPanelTouchMove"/,
  "discovery shell should capture touchmove before nested scroll-view consumes the gesture"
);

assert.equal(
  canExpandDiscoveryPanelFromScroll({
    isTouching: false,
    touchDirection: "",
    lastDownGestureAt: 1000,
    now: 1400,
    gestureRetainMs: 800,
  }),
  true,
  "momentum scroll after a down gesture should still be allowed to reveal the welcome panel"
);

assert.equal(
  canExpandDiscoveryPanelFromScroll({
    isTouching: false,
    touchDirection: "",
    lastDownGestureAt: 1000,
    now: 1901,
    gestureRetainMs: 800,
  }),
  false,
  "old reverse scroll should not be treated as an active down gesture"
);

assert.equal(
  canExpandDiscoveryPanelFromScroll({
    isTouching: true,
    touchDirection: "up",
    lastDownGestureAt: 1000,
    now: 1200,
    gestureRetainMs: 800,
  }),
  false,
  "an active upward gesture should block reveal even if a down gesture happened earlier"
);