/**
 * Unit tests for todoService — TODO-SVC-001 through TODO-SVC-020.
 * Uses a real in-memory SQLite DB so SQL logic is exercised faithfully.
 */
import { describe, it, expect, vi, beforeAll, beforeEach, afterAll } from 'vitest';

// ── DB setup ──────────────────────────────────────────────────────────────────

const { testDb, dbMock } = vi.hoisted(() => {
  const Database = require('better-sqlite3');
  const db = new Database(':memory:');
  db.exec('PRAGMA journal_mode = WAL');
  db.exec('PRAGMA foreign_keys = ON');
  db.exec('PRAGMA busy_timeout = 5000');
  const mock = {
    db,
    closeDb: () => {},
    reinitialize: () => {},
    getPlaceWithTags: () => null,
    canAccessTrip: (tripId: any, userId: number) =>
      db.prepare(`
        SELECT t.id, t.user_id FROM trips t
        LEFT JOIN trip_members m ON m.trip_id = t.id AND m.user_id = ?
        WHERE t.id = ? AND (t.user_id = ? OR m.user_id IS NOT NULL)
      `).get(userId, tripId, userId),
    isOwner: (tripId: any, userId: number) =>
      !!db.prepare('SELECT id FROM trips WHERE id = ? AND user_id = ?').get(tripId, userId),
  };
  return { testDb: db, dbMock: mock };
});

vi.mock('../../../src/db/database', () => dbMock);
vi.mock('../../../src/config', () => ({
  JWT_SECRET: 'test-secret',
  ENCRYPTION_KEY: 'a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6a7b8c9d0e1f2a3b4c5d6a7b8c9d0e1f2',
  updateJwtSecret: () => {},
}));

import { createTables } from '../../../src/db/schema';
import { runMigrations } from '../../../src/db/migrations';
import { resetTestDb } from '../../helpers/test-db';
import { createUser, createTrip, addTripMember } from '../../helpers/factories';
import {
  verifyTripAccess,
  listItems,
  createItem,
  updateItem,
  deleteItem,
  getCategoryAssignees,
  updateCategoryAssignees,
  reorderItems,
} from '../../../src/services/todoService';

beforeAll(() => {
  createTables(testDb);
  runMigrations(testDb);
});

beforeEach(() => {
  resetTestDb(testDb);
});

afterAll(() => {
  testDb.close();
});

// ── verifyTripAccess ──────────────────────────────────────────────────────────

describe('verifyTripAccess', () => {
  it('TODO-SVC-001: returns trip for owner', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    const result = verifyTripAccess(trip.id, user.id);
    expect(result).toBeDefined();
    expect((result as any).id).toBe(trip.id);
  });

  it('TODO-SVC-002: returns null for non-member', () => {
    const { user: owner } = createUser(testDb);
    const { user: stranger } = createUser(testDb);
    const trip = createTrip(testDb, owner.id);
    expect(verifyTripAccess(trip.id, stranger.id)).toBeFalsy();
  });

  it('TODO-SVC-003: returns trip for member', () => {
    const { user: owner } = createUser(testDb);
    const { user: member } = createUser(testDb);
    const trip = createTrip(testDb, owner.id);
    addTripMember(testDb, trip.id, member.id);
    const result = verifyTripAccess(trip.id, member.id);
    expect(result).toBeDefined();
  });
});

// ── listItems / createItem ────────────────────────────────────────────────────

describe('listItems and createItem', () => {
  it('TODO-SVC-004: listItems returns empty array for new trip', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    expect(listItems(trip.id)).toEqual([]);
  });

  it('TODO-SVC-005: createItem inserts a todo with name only', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    const item = createItem(trip.id, { name: 'Buy snacks' }) as any;
    expect(item).toBeDefined();
    expect(item.name).toBe('Buy snacks');
    expect(item.checked).toBe(0);
    expect(item.trip_id).toBe(trip.id);
    expect(item.sort_order).toBe(0);
  });

  it('TODO-SVC-006: createItem assigns incrementing sort_order', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    const a = createItem(trip.id, { name: 'A' }) as any;
    const b = createItem(trip.id, { name: 'B' }) as any;
    expect(b.sort_order).toBe(a.sort_order + 1);
  });

  it('TODO-SVC-007: createItem stores optional fields', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    const item = createItem(trip.id, {
      name: 'Pack bag',
      category: 'Prep',
      description: 'All the gear',
      priority: 3,
    }) as any;
    expect(item.category).toBe('Prep');
    expect(item.description).toBe('All the gear');
    expect(item.priority).toBe(3);
  });

  it('TODO-SVC-008: listItems returns items ordered by sort_order', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    createItem(trip.id, { name: 'First' });
    createItem(trip.id, { name: 'Second' });
    createItem(trip.id, { name: 'Third' });
    const items = listItems(trip.id) as any[];
    expect(items).toHaveLength(3);
    expect(items[0].sort_order).toBeLessThanOrEqual(items[1].sort_order);
    expect(items[1].sort_order).toBeLessThanOrEqual(items[2].sort_order);
  });
});

// ── updateItem ────────────────────────────────────────────────────────────────

describe('updateItem', () => {
  it('TODO-SVC-009: returns null for non-existent item', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    expect(updateItem(trip.id, 99999, { name: 'Ghost' }, ['name'])).toBeNull();
  });

  it('TODO-SVC-010: toggles checked status', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    const item = createItem(trip.id, { name: 'Visit museum' }) as any;
    const updated = updateItem(trip.id, item.id, { checked: 1 }, ['checked']) as any;
    expect(updated.checked).toBe(1);
    const back = updateItem(trip.id, item.id, { checked: 0 }, ['checked']) as any;
    expect(back.checked).toBe(0);
  });

  it('TODO-SVC-011: updates name and category', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    const item = createItem(trip.id, { name: 'Old' }) as any;
    const updated = updateItem(trip.id, item.id, { name: 'New', category: 'Misc' }, ['name', 'category']) as any;
    expect(updated.name).toBe('New');
    expect(updated.category).toBe('Misc');
  });

  it('TODO-SVC-012: clears due_date when key is present with null value', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    const item = createItem(trip.id, { name: 'Task', due_date: '2026-06-01' }) as any;
    const updated = updateItem(trip.id, item.id, { due_date: null }, ['due_date']) as any;
    expect(updated.due_date).toBeNull();
  });
});

// ── deleteItem ────────────────────────────────────────────────────────────────

describe('deleteItem', () => {
  it('TODO-SVC-013: returns false for non-existent item', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    expect(deleteItem(trip.id, 99999)).toBe(false);
  });

  it('TODO-SVC-014: deletes item and returns true', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    const item = createItem(trip.id, { name: 'Gone' }) as any;
    expect(deleteItem(trip.id, item.id)).toBe(true);
    expect(listItems(trip.id)).toHaveLength(0);
  });
});

// ── reorderItems ──────────────────────────────────────────────────────────────

describe('reorderItems', () => {
  it('TODO-SVC-015: assigns sort_order matching orderedIds array position', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    const a = createItem(trip.id, { name: 'A' }) as any;
    const b = createItem(trip.id, { name: 'B' }) as any;
    const c = createItem(trip.id, { name: 'C' }) as any;

    reorderItems(trip.id, [c.id, a.id, b.id]);

    const rows = testDb.prepare('SELECT id, sort_order FROM todo_items WHERE trip_id = ? ORDER BY sort_order').all(trip.id) as any[];
    expect(rows[0].id).toBe(c.id);
    expect(rows[1].id).toBe(a.id);
    expect(rows[2].id).toBe(b.id);
  });
});

// ── category assignees ────────────────────────────────────────────────────────

describe('getCategoryAssignees / updateCategoryAssignees', () => {
  it('TODO-SVC-016: returns empty object for new trip', () => {
    const { user } = createUser(testDb);
    const trip = createTrip(testDb, user.id);
    expect(getCategoryAssignees(trip.id)).toEqual({});
  });

  it('TODO-SVC-017: updateCategoryAssignees sets assignees for a category', () => {
    const { user: owner } = createUser(testDb);
    const { user: member } = createUser(testDb);
    const trip = createTrip(testDb, owner.id);
    addTripMember(testDb, trip.id, member.id);

    const rows = updateCategoryAssignees(trip.id, 'Packing', [owner.id, member.id]) as any[];
    expect(rows).toHaveLength(2);

    const assignees = getCategoryAssignees(trip.id) as any;
    expect(assignees['Packing']).toHaveLength(2);
  });

  it('TODO-SVC-018: updateCategoryAssignees with empty array clears assignees', () => {
    const { user: owner } = createUser(testDb);
    const trip = createTrip(testDb, owner.id);

    updateCategoryAssignees(trip.id, 'Packing', [owner.id]);
    const cleared = updateCategoryAssignees(trip.id, 'Packing', []) as any[];
    expect(cleared).toHaveLength(0);

    const assignees = getCategoryAssignees(trip.id) as any;
    expect(assignees['Packing']).toBeUndefined();
  });

  it('TODO-SVC-019: getCategoryAssignees groups by category name', () => {
    const { user: owner } = createUser(testDb);
    const { user: member } = createUser(testDb);
    const trip = createTrip(testDb, owner.id);
    addTripMember(testDb, trip.id, member.id);

    updateCategoryAssignees(trip.id, 'Shopping', [owner.id]);
    updateCategoryAssignees(trip.id, 'Logistics', [member.id]);

    const assignees = getCategoryAssignees(trip.id) as any;
    expect(Object.keys(assignees)).toHaveLength(2);
    expect(assignees['Shopping']).toHaveLength(1);
    expect(assignees['Logistics']).toHaveLength(1);
  });

  it('TODO-SVC-020: updateCategoryAssignees replaces existing assignees (not append)', () => {
    const { user: owner } = createUser(testDb);
    const { user: member } = createUser(testDb);
    const trip = createTrip(testDb, owner.id);
    addTripMember(testDb, trip.id, member.id);

    updateCategoryAssignees(trip.id, 'Food', [owner.id, member.id]);
    // Replace with just owner
    updateCategoryAssignees(trip.id, 'Food', [owner.id]);

    const assignees = getCategoryAssignees(trip.id) as any;
    expect(assignees['Food']).toHaveLength(1);
    expect(assignees['Food'][0].user_id).toBe(owner.id);
  });
});