// Contract tests for the storage layer, run against the web (Dexie) repo.
//
// fake-indexeddb/auto polyfills IndexedDB into the Node global so Dexie works
// under vitest. We test the Dexie repo as the reference implementation of the
// StorageRepo contract; the native expo-sqlite repo (native-only) is NOT
// imported here because expo-sqlite cannot load outside a device/simulator.
//
// IMPORTANT: repo.web.ts is *not* statically imported. To exercise the v1->v2
// migration we must first seed a v1-shaped DB with a raw Dexie connection, and
// only THEN import repo.web (whose module-eval opens the DB at v2, triggering
// the upgrade). The dynamically-imported repo is stashed in a module-level
// binding so all subsequent tests reuse it.
import 'fake-indexeddb/auto';

import Dexie from 'dexie';
import { describe, it, expect, beforeAll, beforeEach } from 'vitest';
import {
  parseDraft,
  type TranscriptDraft,
  type StorageRepo,
} from './index';

// Populated by the migration beforeAll (which seeds v1 then imports repo.web).
let repo: StorageRepo;

// The v1 record we seed: NO segment ids, NO courseId, but WITH a searchText
// column (exactly the legacy shape the v1 repo persisted).
const V1_ID = 't_legacy';
const v1Row = {
  id: V1_ID,
  title: 'Legacy Lecture',
  createdAt: 1000,
  updatedAt: 1000,
  durationSec: 42.5,
  modelId: 'tiny.en' as const,
  segmentCount: 2,
  segments: [
    { start: 0, end: 2, text: 'legacy hello' },
    { start: 2, end: 5, text: 'legacy world', confidence: 0.8 },
  ],
  searchText: 'legacy lecture\nlegacy hello\nlegacy world',
};

beforeAll(async () => {
  // 1) Seed a v1 DB with a raw Dexie connection (only the v1 store/schema).
  const v1 = new Dexie('wisp');
  v1.version(1).stores({ transcripts: 'id, createdAt' });
  await v1.open();
  await v1.table('transcripts').put(v1Row);
  v1.close();

  // 2) Now import repo.web, which opens 'wisp' at v2 and runs the upgrade.
  const mod = await import('./repo.web');
  repo = mod.repo;

  // Stub object-URL creation so getMediaUrl returns a string under Node.
  globalThis.URL.createObjectURL = () => 'blob:mock';
});

// Helper: a minimal valid draft, overridable per test.
function makeDraft(over: Partial<TranscriptDraft> = {}): TranscriptDraft {
  return {
    title: 'My Recording',
    durationSec: 12.5,
    modelId: 'tiny.en',
    segments: [
      { start: 0, end: 2, text: 'hello world' },
      { start: 2, end: 5, text: 'second segment', confidence: 0.9 },
    ],
    ...over,
  };
}

describe('v1 -> v2 migration (no data loss)', () => {
  it('keeps the legacy transcript, backfills segment ids, leaves it Unsorted', async () => {
    const fetched = await repo.get(V1_ID);
    expect(fetched).toBeDefined();

    // Identity-preserving fields survive untouched.
    expect(fetched!.title).toBe('Legacy Lecture');
    expect(fetched!.durationSec).toBe(42.5);

    // Segment text/timing is identical to the v1 body...
    expect(fetched!.segments.map((s) => s.text)).toEqual([
      'legacy hello',
      'legacy world',
    ]);
    expect(fetched!.segments.map((s) => ({ start: s.start, end: s.end }))).toEqual([
      { start: 0, end: 2 },
      { start: 2, end: 5 },
    ]);
    expect(fetched!.segments[1]!.confidence).toBe(0.8);

    // ...but every segment now carries a backfilled stable id.
    for (const s of fetched!.segments) {
      expect(s.id).toMatch(/^s_/);
    }

    // No courseId was set by v1 => the row is "Unsorted" (null/undefined).
    expect(fetched!.courseId == null).toBe(true);

    // And it shows up under the Unsorted bucket.
    const unsorted = await repo.listByCourse(null);
    expect(unsorted.map((m) => m.id)).toContain(V1_ID);
  });
});

describe('StorageRepo (Dexie web impl)', () => {
  // Wipe transcripts/courses/media between tests so ordering/search/course
  // assertions are deterministic. (Runs after the migration beforeAll.)
  beforeEach(async () => {
    const all = await repo.list();
    await Promise.all(all.map((m) => repo.remove(m.id)));
    const courses = await repo.listCourses();
    await Promise.all(courses.map((c) => repo.deleteCourse(c.id)));
  });

  it('create -> get round-trips segments and metadata, assigns segment ids', async () => {
    const created = await repo.create(makeDraft());

    expect(created.id).toMatch(/^t_/);
    expect(created.createdAt).toBeTypeOf('number');
    expect(created.updatedAt).toBe(created.createdAt);
    expect(created.segmentCount).toBe(2);
    // courseId defaults to null ("Unsorted") when absent.
    expect(created.courseId).toBeNull();
    expect(created.hasMedia).toBe(false);
    // Every segment got a stable id assigned on write.
    for (const s of created.segments) {
      expect(s.id).toMatch(/^s_/);
    }

    const fetched = await repo.get(created.id);
    expect(fetched).toBeDefined();
    expect(fetched!.title).toBe('My Recording');
    expect(fetched!.durationSec).toBe(12.5);
    expect(fetched!.modelId).toBe('tiny.en');
    // Text/timing survive the round-trip exactly.
    expect(fetched!.segments.map((s) => ({ start: s.start, end: s.end, text: s.text }))).toEqual([
      { start: 0, end: 2, text: 'hello world' },
      { start: 2, end: 5, text: 'second segment' },
    ]);
    expect(fetched!.segments[1]!.confidence).toBe(0.9);
  });

  it('get returns undefined for an unknown id', async () => {
    expect(await repo.get('t_nope')).toBeUndefined();
  });

  it('list returns metadatas newest-first (without segments)', async () => {
    const a = await repo.create(makeDraft({ title: 'first' }));
    await new Promise((r) => setTimeout(r, 2));
    const b = await repo.create(makeDraft({ title: 'second' }));
    await new Promise((r) => setTimeout(r, 2));
    const c = await repo.create(makeDraft({ title: 'third' }));

    const metas = await repo.list();
    expect(metas.map((m) => m.id)).toEqual([c.id, b.id, a.id]);
    expect((metas[0] as unknown as Record<string, unknown>).segments).toBeUndefined();
    expect(metas[0]!.segmentCount).toBe(2);
  });

  it('update merges title/segments/courseId and re-ids segments + re-derives search', async () => {
    const course = await repo.createCourse({ name: 'Physics' });
    const created = await repo.create(
      makeDraft({ title: 'Old Title', segments: [{ start: 0, end: 1, text: 'apple' }] }),
    );
    const originalUpdatedAt = created.updatedAt;
    await new Promise((r) => setTimeout(r, 2));

    const updated = await repo.update(created.id, {
      title: 'Brand New Title',
      courseId: course.id,
      segments: [
        { start: 0, end: 1, text: 'banana' },
        { start: 1, end: 2, text: 'cherry' },
      ],
    });

    expect(updated.title).toBe('Brand New Title');
    expect(updated.courseId).toBe(course.id);
    expect(updated.segmentCount).toBe(2);
    expect(updated.updatedAt).toBeGreaterThan(originalUpdatedAt);
    // New segments got ids.
    for (const s of updated.segments) {
      expect(s.id).toMatch(/^s_/);
    }

    // Old text is no longer findable...
    expect(await repo.search('apple')).toHaveLength(0);
    // ...and the new text + new title are.
    expect((await repo.search('cherry')).map((m) => m.id)).toEqual([created.id]);
    expect((await repo.search('brand new')).map((m) => m.id)).toEqual([created.id]);
  });

  it('update throws for an unknown id', async () => {
    await expect(repo.update('t_missing', { title: 'x' })).rejects.toThrow();
  });

  it('search matches title and segment text case-insensitively', async () => {
    const t = await repo.create(
      makeDraft({
        title: 'Quarterly MEETING notes',
        segments: [{ start: 0, end: 3, text: 'Discuss the BUDGET forecast' }],
      }),
    );

    expect((await repo.search('meeting')).map((m) => m.id)).toEqual([t.id]);
    expect((await repo.search('budget')).map((m) => m.id)).toEqual([t.id]);
    expect(await repo.search('zzz-not-present')).toHaveLength(0);
  });

  it('remove deletes a transcript (and its media)', async () => {
    const created = await repo.create(makeDraft());
    await repo.putMedia(created.id, { data: new ArrayBuffer(4), mime: 'audio/mpeg' });
    expect(await repo.get(created.id)).toBeDefined();

    await repo.remove(created.id);
    expect(await repo.get(created.id)).toBeUndefined();
    expect(await repo.list()).toHaveLength(0);
    // Media is gone too: no playable URL remains.
    expect(await repo.getMediaUrl(created.id)).toBeUndefined();
  });

  // --- courses -------------------------------------------------------------

  it('listByCourse splits Unsorted vs a course', async () => {
    const course = await repo.createCourse({ name: 'Bio 101' });
    const inCourse = await repo.create(makeDraft({ title: 'lecture', courseId: course.id }));
    const unsorted = await repo.create(makeDraft({ title: 'loose note' }));

    const courseRows = await repo.listByCourse(course.id);
    expect(courseRows.map((m) => m.id)).toEqual([inCourse.id]);

    const unsortedRows = await repo.listByCourse(null);
    expect(unsortedRows.map((m) => m.id)).toEqual([unsorted.id]);
  });

  it('createCourse / listCourses (alphabetical) / updateCourse', async () => {
    const zebra = await repo.createCourse({ name: 'Zebra Studies', code: 'ZOO-1' });
    const apple = await repo.createCourse({ name: 'Apple Theory' });

    expect(apple.id).toMatch(/^c_/);
    expect(apple.createdAt).toBeTypeOf('number');

    // Alphabetical by name.
    const listed = await repo.listCourses();
    expect(listed.map((c) => c.name)).toEqual(['Apple Theory', 'Zebra Studies']);

    const renamed = await repo.updateCourse(zebra.id, { name: 'Aardvark Studies' });
    expect(renamed.name).toBe('Aardvark Studies');
    expect(renamed.code).toBe('ZOO-1'); // unspecified fields preserved
    expect(renamed.updatedAt).toBeGreaterThanOrEqual(zebra.updatedAt);

    const relisted = await repo.listCourses();
    expect(relisted.map((c) => c.name)).toEqual(['Aardvark Studies', 'Apple Theory']);
  });

  it('deleteCourse reassigns its transcripts to Unsorted, then removes the course', async () => {
    const course = await repo.createCourse({ name: 'Doomed' });
    const t = await repo.create(makeDraft({ title: 'orphan-to-be', courseId: course.id }));

    await repo.deleteCourse(course.id);

    // The course is gone.
    expect((await repo.listCourses()).map((c) => c.id)).not.toContain(course.id);
    // The transcript survives, now Unsorted.
    const fetched = await repo.get(t.id);
    expect(fetched).toBeDefined();
    expect(fetched!.courseId).toBeNull();
    expect((await repo.listByCourse(null)).map((m) => m.id)).toContain(t.id);
  });

  it('reassign moves a transcript between courses and to Unsorted', async () => {
    const course = await repo.createCourse({ name: 'Chemistry' });
    const t = await repo.create(makeDraft());
    expect(t.courseId).toBeNull();

    await repo.reassign(t.id, course.id);
    expect((await repo.listByCourse(course.id)).map((m) => m.id)).toEqual([t.id]);

    await repo.reassign(t.id, null);
    expect((await repo.listByCourse(course.id))).toHaveLength(0);
    expect((await repo.listByCourse(null)).map((m) => m.id)).toContain(t.id);
  });

  // --- media ---------------------------------------------------------------

  it('putMedia flips hasMedia true and getMediaUrl returns a url; removeMedia flips it false', async () => {
    const t = await repo.create(makeDraft());
    expect(t.hasMedia).toBe(false);

    await repo.putMedia(t.id, { data: new ArrayBuffer(8), mime: 'audio/mpeg' });

    const afterPut = await repo.get(t.id);
    expect(afterPut!.hasMedia).toBe(true);
    expect(await repo.getMediaUrl(t.id)).toBe('blob:mock');

    await repo.removeMedia(t.id);
    const afterRemove = await repo.get(t.id);
    expect(afterRemove!.hasMedia).toBe(false);
    expect(await repo.getMediaUrl(t.id)).toBeUndefined();
  });

  // --- validation gatekeeping ---------------------------------------------

  it('parseDraft rejects a NaN/Infinity duration', () => {
    expect(() => parseDraft(makeDraft({ durationSec: NaN }))).toThrow();
    expect(() => parseDraft(makeDraft({ durationSec: Infinity }))).toThrow();
  });

  it('parseDraft rejects a non-finite segment time', () => {
    expect(() =>
      parseDraft(makeDraft({ segments: [{ start: 0, end: Infinity, text: 'x' }] })),
    ).toThrow();
    expect(() =>
      parseDraft(makeDraft({ segments: [{ start: NaN, end: 1, text: 'x' }] })),
    ).toThrow();
  });

  it('create rejects an invalid draft (defense in depth)', async () => {
    await expect(repo.create(makeDraft({ durationSec: -1 }))).rejects.toThrow();
  });
});