import { describe, expect, it } from 'vitest';
import {
  buildInitialState,
  buildPickerTree,
  canToggle,
  clearExpiredTransientHint,
  filterTree,
  flattenSelection,
  moveCursor,
  reducer,
  selectAllVisible,
  selectNone,
  toggleChecked,
  TRANSIENT_HINT_DURATION_MS,
  visibleNodeIds,
  type NotionPickerPageInput,
} from './connection-notion-tree.js';

const IDS = {
  engineering: '11111111-1111-1111-1111-111111111111',
  architecture: '22222222-2222-2222-2222-222222222222',
  onboarding: '33333333-3333-3333-3333-333333333333',
  marketing: '44444444-4444-4444-4444-444444444444',
  journal: '55555555-5555-5555-5555-555555555555',
  orphan: '66666666-6666-6666-6666-666666666666',
  duplicate: '77777777-7777-7777-7777-777777777777',
  cycleA: '88888888-8888-8888-8888-888888888888',
  cycleB: '99999999-9999-9999-9999-999999999999',
};

function pages(): NotionPickerPageInput[] {
  return [
    { id: IDS.marketing, title: 'Marketing', archived: false, parentId: null },
    { id: IDS.onboarding, title: 'Onboarding', archived: false, parentId: IDS.engineering },
    { id: IDS.engineering, title: 'Engineering Docs', archived: false, parentId: null },
    { id: IDS.architecture, title: 'Architecture', archived: false, parentId: IDS.engineering },
    { id: IDS.journal, title: 'Daily journal', archived: true, parentId: IDS.marketing },
    { id: IDS.orphan, title: '', archived: false, parentId: 'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa' },
    { id: IDS.duplicate, title: 'Original duplicate', archived: false, parentId: null },
    { id: IDS.duplicate, title: 'Ignored duplicate', archived: true, parentId: IDS.marketing },
    { id: IDS.cycleA, title: 'Cycle A', archived: false, parentId: IDS.cycleB },
    { id: IDS.cycleB, title: 'Cycle B', archived: false, parentId: IDS.cycleA },
  ];
}

describe('buildPickerTree', () => {
  it('deduplicates pages, sorts siblings, preserves archived flags, roots orphans, and breaks cycles', () => {
    const tree = buildPickerTree(pages());
    const byId = new Map(tree.map((node) => [node.id, node]));

    expect(tree.map((node) => node.title)).toEqual([
      'Cycle A',
      'Cycle B',
      'Engineering Docs',
      'Architecture',
      'Onboarding',
      'Marketing',
      'Daily journal',
      'Original duplicate',
      'Untitled',
    ]);
    expect(byId.get(IDS.engineering)?.childIds).toEqual([IDS.architecture, IDS.onboarding]);
    expect(byId.get(IDS.architecture)).toMatchObject({
      depth: 1,
      parentId: IDS.engineering,
      path: 'Engineering Docs / Architecture',
    });
    expect(byId.get(IDS.journal)).toMatchObject({
      archived: true,
      depth: 1,
      path: 'Marketing / Daily journal',
    });
    expect(byId.get(IDS.orphan)).toMatchObject({
      title: 'Untitled',
      parentId: null,
      depth: 0,
      path: 'Untitled',
    });
    expect(byId.get(IDS.duplicate)).toMatchObject({
      title: 'Original duplicate',
      archived: false,
      parentId: null,
    });
    expect(byId.get(IDS.cycleA)?.parentId).toBeNull();
    expect(byId.get(IDS.cycleB)?.parentId).toBe(IDS.cycleA);
  });
});

describe('selection invariants', () => {
  it('checking a parent locks descendants and keeps checked ids minimal', () => {
    const state = buildInitialState({
      tree: buildPickerTree(pages()),
      existingRootPageIds: [],
      currentCrawlMode: 'selected_roots',
    });

    const checkedParent = toggleChecked(state, IDS.engineering, 1000);
    expect([...checkedParent.checked]).toEqual([IDS.engineering]);
    expect(canToggle(IDS.architecture, checkedParent)).toEqual({
      ok: false,
      reason: "Locked by 'Engineering Docs' - uncheck parent first",
    });

    const lockedChildAttempt = toggleChecked(checkedParent, IDS.architecture, 2000);
    expect([...lockedChildAttempt.checked]).toEqual([IDS.engineering]);
    expect(lockedChildAttempt.transientHint).toEqual({
      text: "Locked by 'Engineering Docs' - uncheck parent first",
      expiresAt: 4500,
    });

    const uncheckedParent = toggleChecked(lockedChildAttempt, IDS.engineering, 3000);
    expect([...uncheckedParent.checked]).toEqual([]);
    expect(canToggle(IDS.architecture, uncheckedParent)).toEqual({ ok: true });
  });

  it('normalizes stored roots, reports stale roots, expands checked ancestors, and flattens descendants', () => {
    const state = buildInitialState({
      tree: buildPickerTree(pages()),
      existingRootPageIds: [
        IDS.engineering.replaceAll('-', ''),
        IDS.architecture,
        'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa',
      ],
      currentCrawlMode: 'selected_roots',
    });

    expect([...state.checked]).toEqual([IDS.engineering]);
    expect([...state.expanded]).toEqual([]);
    expect(state.cursorId).toBe(IDS.cycleA);
    expect(state.preLoadWarnings).toEqual(['1 stored root_page_ids no longer visible']);
    expect(flattenSelection(new Set([IDS.engineering, IDS.architecture]), state.byId)).toEqual([IDS.engineering]);
  });
});

describe('search and cursor movement', () => {
  it('filters by title and path while deriving auto-expanded ancestors', () => {
    const state = buildInitialState({
      tree: buildPickerTree(pages()),
      existingRootPageIds: [],
      currentCrawlMode: 'selected_roots',
    });
    const searching = {
      ...state,
      search: { editing: false, query: 'architecture' },
    };

    expect(filterTree(searching)).toEqual({
      visibleIds: new Set([IDS.engineering, IDS.architecture]),
      autoExpand: new Set([IDS.engineering]),
    });
    expect(visibleNodeIds(searching)).toEqual([IDS.engineering, IDS.architecture]);
  });

  it('moves the cursor through visible nodes and implements left/right tree semantics', () => {
    const state = buildInitialState({
      tree: buildPickerTree(pages()),
      existingRootPageIds: [],
      currentCrawlMode: 'selected_roots',
    });

    const atEngineering = {
      ...state,
      cursorId: IDS.engineering,
      expanded: new Set([IDS.engineering]),
    };
    expect(moveCursor(atEngineering, 'down').cursorId).toBe(IDS.architecture);
    expect(moveCursor({ ...atEngineering, cursorId: IDS.architecture }, 'up').cursorId).toBe(IDS.engineering);
    expect(moveCursor(atEngineering, 'right').cursorId).toBe(IDS.architecture);
    expect(moveCursor({ ...atEngineering, cursorId: IDS.architecture }, 'left').cursorId).toBe(IDS.engineering);
    expect([...moveCursor(atEngineering, 'left').expanded]).toEqual([]);
    expect([...moveCursor({ ...state, cursorId: IDS.marketing }, 'right').expanded]).toContain(IDS.marketing);
  });
});

describe('bulk actions and reducer effects', () => {
  it('selects only matching visible roots under search and clears selection', () => {
    const state = buildInitialState({
      tree: buildPickerTree(pages()),
      existingRootPageIds: [IDS.marketing],
      currentCrawlMode: 'selected_roots',
    });
    const searching = {
      ...state,
      search: { editing: false, query: 'architecture' },
    };

    const selected = selectAllVisible(searching);
    expect(flattenSelection(selected.checked, selected.byId)).toEqual([IDS.architecture, IDS.marketing]);
    expect([...selectNone(selected).checked]).toEqual([]);
  });

  it('returns save immediately for selected_roots and requires confirmation for all_accessible', () => {
    const selectedRoots = toggleChecked(
      buildInitialState({
        tree: buildPickerTree(pages()),
        existingRootPageIds: [],
        currentCrawlMode: 'selected_roots',
      }),
      IDS.marketing,
      1000,
    );
    expect(reducer(selectedRoots, 'save-request')).toEqual({
      next: selectedRoots,
      effect: 'save',
    });

    const allAccessible = {
      ...selectedRoots,
      currentCrawlMode: 'all_accessible' as const,
    };
    const confirm = reducer(allAccessible, 'save-request');
    expect(confirm).toEqual({
      next: { ...allAccessible, pendingConfirm: 'mode-switch' },
      effect: null,
    });
    expect(reducer(confirm.next, 'save-cancel')).toEqual({
      next: { ...allAccessible, pendingConfirm: null },
      effect: null,
    });
    expect(reducer(confirm.next, 'save-confirm')).toEqual({
      next: { ...allAccessible, pendingConfirm: null },
      effect: 'save',
    });
  });

  it('blocks empty saves, updates search state, and quits without saving', () => {
    const state = buildInitialState({
      tree: buildPickerTree(pages()),
      existingRootPageIds: [],
      currentCrawlMode: 'selected_roots',
    });

    const blockedSave = reducer(state, 'save-request', 9000);
    expect(blockedSave).toEqual({
      next: {
        ...state,
        transientHint: {
          text: 'Select at least one page or press q to quit',
          expiresAt: 9000 + TRANSIENT_HINT_DURATION_MS,
        },
      },
      effect: null,
    });
    expect(
      reducer(
        reducer(reducer(state, 'search-start').next, { type: 'search-input', value: 'a' }).next,
        'search-submit',
      ).next.search,
    ).toEqual({ editing: false, query: 'a' });
    expect(reducer(state, 'quit')).toEqual({
      next: state,
      effect: 'quit-without-save',
    });
  });

  it('clears transient hints only when their expiry time has passed', () => {
    const state = buildInitialState({
      tree: buildPickerTree(pages()),
      existingRootPageIds: [],
      currentCrawlMode: 'selected_roots',
    });
    const withHint = {
      ...state,
      transientHint: {
        text: 'Select at least one page or press q to quit',
        expiresAt: 11500,
      },
    };

    expect(clearExpiredTransientHint(withHint, 11499)).toBe(withHint);
    expect(clearExpiredTransientHint(withHint, 11500)).toEqual({
      ...withHint,
      transientHint: null,
    });
    expect(reducer(withHint, 'clear-transient-hint', 11501)).toEqual({
      next: {
        ...withHint,
        transientHint: null,
      },
      effect: null,
    });
  });
});