import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest';
import { useTimerStore } from '@/store/timerStore';

describe('timerStore', () => {
  beforeEach(() => {
    vi.useFakeTimers();
    useTimerStore.setState({
      currentRate: 50,
      running: false,
      runStartedAt: null,
      accumulatedMs: 0,
      splits: [],
      lastHeartbeat: Date.now(),
      elapsedMs: 0,
      crashRecovery: null,
    });
  });

  afterEach(() => {
    vi.useRealTimers();
  });

  it('starts and tracks elapsed time', () => {
    const s = useTimerStore.getState();
    s.start();
    expect(useTimerStore.getState().running).toBe(true);
    vi.advanceTimersByTime(5000);
    useTimerStore.getState()._tick();
    expect(useTimerStore.getState().elapsedMs).toBeGreaterThanOrEqual(5000);
  });

  it('pause freezes elapsed and stops ticking', () => {
    useTimerStore.getState().start();
    vi.advanceTimersByTime(3000);
    useTimerStore.getState().pause();
    const frozen = useTimerStore.getState().elapsedMs;
    expect(useTimerStore.getState().running).toBe(false);
    vi.advanceTimersByTime(10000);
    expect(useTimerStore.getState().elapsedMs).toBe(frozen);
  });

  it('resume after pause accumulates correctly', () => {
    useTimerStore.getState().start();
    vi.advanceTimersByTime(2000);
    useTimerStore.getState().pause();
    vi.advanceTimersByTime(5000); // paused time doesn't count
    useTimerStore.getState().start();
    vi.advanceTimersByTime(3000);
    useTimerStore.getState()._tick();
    const elapsed = useTimerStore.getState().elapsedMs;
    expect(elapsed).toBeGreaterThanOrEqual(5000);
    expect(elapsed).toBeLessThan(7000); // not 10000
  });

  it('split records current segment and resets clock', () => {
    useTimerStore.getState().start();
    vi.advanceTimersByTime(4000);
    const split = useTimerStore.getState().split('task A');

    expect(split.elapsedMs).toBeGreaterThanOrEqual(4000);
    expect(split.rate).toBe(50);
    expect(split.label).toBe('task A');
    expect(split.recorded).toBe(false);
    expect(useTimerStore.getState().splits).toHaveLength(1);
    // Clock resets but keeps running
    expect(useTimerStore.getState().accumulatedMs).toBe(0);
    expect(useTimerStore.getState().running).toBe(true);
  });

  it('split preserves rate at time of split (rate change after doesn\'t affect)', () => {
    useTimerStore.getState().start();
    vi.advanceTimersByTime(1000);
    const split = useTimerStore.getState().split();
    expect(split.rate).toBe(50);

    useTimerStore.getState().setRate(100);
    expect(useTimerStore.getState().splits[0].rate).toBe(50);
    expect(useTimerStore.getState().currentRate).toBe(100);
  });

  it('setRate only affects live clock, not existing splits', () => {
    useTimerStore.getState().start();
    vi.advanceTimersByTime(1000);
    useTimerStore.getState().split();
    useTimerStore.getState().split();
    useTimerStore.getState().setRate(999);
    expect(useTimerStore.getState().splits.every((s) => s.rate === 50)).toBe(true);
  });

  it('markRecorded sets flag and stores work entry id', () => {
    useTimerStore.getState().start();
    vi.advanceTimersByTime(1000);
    const split = useTimerStore.getState().split();
    useTimerStore.getState().markRecorded(split.id, 'we-123');
    const updated = useTimerStore.getState().splits.find((s) => s.id === split.id)!;
    expect(updated.recorded).toBe(true);
    expect(updated.recordedWorkEntryId).toBe('we-123');
  });

  it('updateSplit modifies fields', () => {
    useTimerStore.getState().start();
    vi.advanceTimersByTime(1000);
    const split = useTimerStore.getState().split();
    useTimerStore.getState().updateSplit(split.id, { label: 'new label', elapsedMs: 9999 });
    const updated = useTimerStore.getState().splits.find((s) => s.id === split.id)!;
    expect(updated.label).toBe('new label');
    expect(updated.elapsedMs).toBe(9999);
  });

  it('deleteSplit removes from table', () => {
    useTimerStore.getState().start();
    vi.advanceTimersByTime(1000);
    const split = useTimerStore.getState().split();
    useTimerStore.getState().deleteSplit(split.id);
    expect(useTimerStore.getState().splits).toHaveLength(0);
  });

  it('reset clears everything', () => {
    useTimerStore.getState().start();
    vi.advanceTimersByTime(1000);
    useTimerStore.getState().split();
    useTimerStore.getState().reset();
    expect(useTimerStore.getState().running).toBe(false);
    expect(useTimerStore.getState().elapsedMs).toBe(0);
    expect(useTimerStore.getState().splits).toHaveLength(0);
  });

  it('persists state to cookie on tick', () => {
    useTimerStore.getState().start();
    vi.advanceTimersByTime(1500);
    useTimerStore.getState()._tick();
    expect(document.cookie).toContain('t99_timer');
  });
});

describe('timerStore crash recovery', () => {
  beforeEach(() => {
    vi.useRealTimers();
  });

  it('detects crash when heartbeat stale + running', () => {
    const now = Date.now();
    const staleSnapshot = {
      currentRate: 75,
      running: true,
      runStartedAt: now - 60000, // started 1 min ago
      accumulatedMs: 0,
      splits: [],
      lastHeartbeat: now - 30000, // last seen 30s ago (> 5s threshold)
    };
    document.cookie = `t99_timer=${encodeURIComponent(JSON.stringify(staleSnapshot))}; path=/`;

    useTimerStore.setState({ crashRecovery: null });
    useTimerStore.getState()._restoreFromCookie();

    const cr = useTimerStore.getState().crashRecovery;
    expect(cr).not.toBeNull();
    expect(cr!.gapMs).toBeGreaterThan(25000);
    expect(cr!.crashTime).toBe(now - 30000);
  });

  it('does NOT flag crash when paused', () => {
    const now = Date.now();
    const snapshot = {
      currentRate: 50,
      running: false,
      runStartedAt: null,
      accumulatedMs: 120000,
      splits: [],
      lastHeartbeat: now - 60000,
    };
    document.cookie = `t99_timer=${encodeURIComponent(JSON.stringify(snapshot))}; path=/`;

    useTimerStore.setState({ crashRecovery: null });
    useTimerStore.getState()._restoreFromCookie();
    expect(useTimerStore.getState().crashRecovery).toBeNull();
  });

  it('restores elapsed time from original start (includes gap)', () => {
    const now = Date.now();
    const snapshot = {
      currentRate: 50,
      running: true,
      runStartedAt: now - 120000, // 2 min ago
      accumulatedMs: 0,
      splits: [],
      lastHeartbeat: now - 60000,
    };
    document.cookie = `t99_timer=${encodeURIComponent(JSON.stringify(snapshot))}; path=/`;

    useTimerStore.getState()._restoreFromCookie();
    // Clock should show ~2 minutes (original start was preserved)
    expect(useTimerStore.getState().elapsedMs).toBeGreaterThanOrEqual(120000);
  });

  it('subtractCrashGap removes gap from accumulated time', () => {
    useTimerStore.setState({
      running: false,
      runStartedAt: null,
      accumulatedMs: 100000,
      crashRecovery: { crashTime: 0, reloadTime: 30000, gapMs: 30000 },
      elapsedMs: 100000,
    });
    useTimerStore.getState().subtractCrashGap();
    expect(useTimerStore.getState().accumulatedMs).toBe(70000);
    expect(useTimerStore.getState().crashRecovery).toBeNull();
  });

  it('subtractCrashGap clamps to zero', () => {
    useTimerStore.setState({
      accumulatedMs: 5000,
      crashRecovery: { crashTime: 0, reloadTime: 0, gapMs: 99999 },
    });
    useTimerStore.getState().subtractCrashGap();
    expect(useTimerStore.getState().accumulatedMs).toBe(0);
  });

  it('dismissCrashBanner keeps time but removes banner', () => {
    useTimerStore.setState({
      accumulatedMs: 100000,
      crashRecovery: { crashTime: 0, reloadTime: 0, gapMs: 30000 },
    });
    useTimerStore.getState().dismissCrashBanner();
    expect(useTimerStore.getState().crashRecovery).toBeNull();
    expect(useTimerStore.getState().accumulatedMs).toBe(100000); // unchanged
  });

  it('restores splits from cookie', () => {
    const snapshot = {
      currentRate: 50,
      running: false,
      runStartedAt: null,
      accumulatedMs: 0,
      splits: [
        { id: 's1', startedAt: 0, elapsedMs: 60000, rate: 50, recorded: false },
        { id: 's2', startedAt: 0, elapsedMs: 30000, rate: 75, recorded: true, recordedWorkEntryId: 'we-1' },
      ],
      lastHeartbeat: Date.now(),
    };
    document.cookie = `t99_timer=${encodeURIComponent(JSON.stringify(snapshot))}; path=/`;
    useTimerStore.getState()._restoreFromCookie();
    expect(useTimerStore.getState().splits).toHaveLength(2);
    expect(useTimerStore.getState().splits[1].recorded).toBe(true);
  });
});