import { afterEach, describe, expect, test, vi } from 'vitest';
import { fireEvent, render, screen } from '@testing-library/svelte';
import { readable } from 'svelte/store';
import type {
  AdminDuplicatesResponse,
  ResolvedDuplicateActivity,
  ResolvedDuplicatesResponse
} from '#lib/api/types.js';

vi.mock('#lib/api/admin.js', () => ({
  createDuplicatesQuery: vi.fn(),
  createResolvedDuplicatesQuery: vi.fn(),
  runDuplicateSweep: vi.fn().mockResolvedValue({ started: true }),
  dismissDuplicateGroup: vi.fn().mockResolvedValue(undefined),
  mergeDuplicateGroup: vi.fn().mockResolvedValue({
    survivor_track_id: 'www-01',
    removed_paths: ['/music/Moe Shop/WWW (2020)/www-02.mp3']
  }),
  refetchDuplicateGroup: vi.fn().mockResolvedValue({
    kept_track_id: null,
    removed_paths: ['/music/Moe Shop/WWW (2020)/www-01.mp3', '/music/Moe Shop/WWW (2020)/www-02.mp3'],
    blocked: ['Moe Shop - WWW [WEB]']
  })
}));
vi.mock('#lib/player/store.svelte.js', () => ({ playQueue: vi.fn() }));

import AdminDuplicatesPage from './+page.svelte';
import { playQueue } from '#lib/player/store.svelte.js';
import {
  createDuplicatesQuery,
  createResolvedDuplicatesQuery,
  dismissDuplicateGroup,
  mergeDuplicateGroup,
  refetchDuplicateGroup,
  runDuplicateSweep
} from '#lib/api/admin.js';

const HOUR = 3_600_000;
const ago = (ms: number) => new Date(Date.now() - ms).toISOString();

const finishedSweep = {
  state: 'finished' as const,
  started_at: ago(2 * HOUR),
  finished_at: ago(HOUR),
  candidates: 1200,
  groups_found: 1,
  oversize_clusters: 0,
  error_message: null
};
const allFingerprinted = { total: 1200, fingerprinted: 1200, rejected: 0, pending: 0, enabled: true };

function member(id: string, extra: Partial<AdminDuplicatesResponse['groups'][number]['members'][number]> = {}) {
  return {
    track_id: id,
    title: 'WWW',
    artist_id: 'ar-1',
    artist_name: 'Moe Shop',
    album_id: 'al-1',
    album_title: 'WWW',
    file_path: `/music/Moe Shop/WWW (2020)/${id}.mp3`,
    file_format: 'mp3',
    file_size: 6_900_000,
    duration_sec: 215,
    added_at: ago(500 * HOUR),
    like_count: 0,
    play_count: 0,
    disc_number: null,
    track_number: null,
    stream_url: `/api/tracks/${id}/stream`,
    ...extra
  };
}

function response(over: Partial<AdminDuplicatesResponse> = {}): AdminDuplicatesResponse {
  return {
    sweep: finishedSweep,
    fingerprints: allFingerprinted,
    view: 'review',
    counts: { review: 1, cross_release: 4, resolved: 2 },
    total: 1,
    limit: 25,
    offset: 0,
    groups: [
      {
        id: 'g-1',
        tier: 'exact',
        worst_bit_error_rate: null,
        detected_at: ago(HOUR),
        survivor_track_id: 'www-01',
        survivor_reason: 'in the library longest',
        class: 'review',
        resolve_note: null,
        members: [member('www-01', { like_count: 2, play_count: 14 }), member('www-02')]
      }
    ],
    ...over
  };
}

// The page reads only these fields of an infinite query.
function infinite<T>(pages: T[]) {
  return readable({
    data: { pages },
    isPending: false,
    isError: false,
    hasNextPage: false,
    isFetchingNextPage: false,
    isFetchNextPageError: false,
    fetchNextPage: () => {},
    refetch: () => {}
  });
}

function resolvedPage(items: ResolvedDuplicateActivity[]): ResolvedDuplicatesResponse {
  return { total: items.length, limit: 25, offset: 0, items };
}

function renderWith(data: AdminDuplicatesResponse, resolved: ResolvedDuplicateActivity[] = []) {
  vi.mocked(createDuplicatesQuery).mockReturnValue(
    infinite([data]) as unknown as ReturnType<typeof createDuplicatesQuery>
  );
  vi.mocked(createResolvedDuplicatesQuery).mockReturnValue(
    infinite([resolvedPage(resolved)]) as unknown as ReturnType<typeof createResolvedDuplicatesQuery>
  );
  return render(AdminDuplicatesPage);
}

function text(el: HTMLElement): string {
  return (el.textContent ?? '').replace(/\s+/g, ' ').trim();
}

afterEach(() => vi.clearAllMocks());

describe('admin duplicates', () => {
  test('shows each group with its members, what they carry, and the copy to keep', () => {
    renderWith(response());
    expect(screen.getAllByTestId('duplicate-group')).toHaveLength(1);
    expect(screen.getAllByTestId('duplicate-member')).toHaveLength(2);
    expect(text(screen.getByTestId('duplicate-tier'))).toBe('Identical audio');
    expect(text(screen.getByTestId('survivor-badge'))).toBe('Keep · in the library longest');
    const history = screen.getAllByTestId('member-history').map(text);
    expect(history).toEqual(['2 likes · 14 plays', 'no likes or plays']);
  });

  // Size and length come from the shared formatters (M505).
  test('each copy shows its format, size and length', () => {
    const group = response().groups[0];
    group.members = [member('www-01'), member('www-02', { file_size: 812_000, duration_sec: 3665 })];
    renderWith(response({ groups: [group] }));
    expect(screen.getAllByTestId('member-file').map(text)).toEqual([
      'MP3 · 6.9 MB · 3:35',
      'MP3 · 812 KB · 1:01:05'
    ]);
  });

  // The badge must sit on the proposed survivor, not merely appear somewhere.
  test('the keep badge is on the survivor row', () => {
    renderWith(response());
    const rows = screen.getAllByTestId('duplicate-member');
    expect(rows[0].querySelector('[data-testid="survivor-badge"]')).not.toBeNull();
    expect(rows[1].querySelector('[data-testid="survivor-badge"]')).toBeNull();
  });

  test('picking another copy moves the keep badge to it', async () => {
    renderWith(response());
    const rows = screen.getAllByTestId('duplicate-member');
    await fireEvent.click(rows[1].querySelector('input[type="radio"]') as HTMLInputElement);
    const after = screen.getAllByTestId('duplicate-member');
    expect(after[0].querySelector('[data-testid="survivor-badge"]')).toBeNull();
    expect(text(after[1].querySelector('[data-testid="survivor-badge"]') as HTMLElement)).toBe('Keep · your pick');
  });

  test('an acoustic group reads as a match percentage', () => {
    const r = response();
    r.groups[0] = { ...r.groups[0], tier: 'acoustic', worst_bit_error_rate: 0.04 };
    renderWith(r);
    expect(text(screen.getByTestId('duplicate-tier'))).toBe('Same music · 96% match');
  });

  // The operator took the match for a guess from size and length (#6168).
  test('each group says what the match rests on', () => {
    const r = response();
    r.groups.push({ ...r.groups[0], id: 'g-2', tier: 'acoustic', worst_bit_error_rate: 0.04 });
    renderWith(r);
    const lines = screen.getAllByTestId('match-evidence').map(text);
    expect(lines[0]).toContain('the same audio data, byte for byte');
    expect(lines[1]).toBe(
      'Matched by listening, not by size or length: 96% of their audio fingerprints agree, so these files play the same music.'
    );
  });

  test('each copy can be played', async () => {
    renderWith(response());
    const plays = screen.getAllByTestId('member-play');
    expect(plays).toHaveLength(2);
    await fireEvent.click(plays[1]);
    expect(playQueue).toHaveBeenLastCalledWith(
      [expect.objectContaining({ id: 'www-02', artist_id: 'ar-1', stream_url: '/api/tracks/www-02/stream' })],
      0
    );
  });

  // #3885: identical audio titled "WWW" and "WWW (instrumental)". One file
  // claimed to be the vocal and wasn't, and nothing said the vocal was missing.
  describe('identical audio under different titles', () => {
    function www() {
      const r = response();
      r.groups[0] = {
        ...r.groups[0],
        members: [member('www-01'), member('www-02', { title: 'WWW (instrumental)' })]
      };
      return r;
    }

    test('says the copies are titled differently and names both titles', () => {
      renderWith(www());
      const notice = text(screen.getByTestId('title-mismatch'));
      expect(notice).toContain('titled “WWW” and “WWW (instrumental)”');
      expect(notice).toContain("isn't in your library");
    });

    test('three different titles are all named', () => {
      const r = www();
      r.groups[0].members.push(member('www-03', { title: 'WWW (Radio Edit)' }));
      renderWith(r);
      expect(text(screen.getByTestId('title-mismatch'))).toContain(
        '“WWW”, “WWW (instrumental)” and “WWW (Radio Edit)”'
      );
    });

    test('titles differing only in case or spacing are the same title', () => {
      const r = response();
      r.groups[0] = {
        ...r.groups[0],
        members: [
          member('www-01', { title: 'WWW (Instrumental)' }),
          member('www-02', { title: ' www  (instrumental) ' })
        ]
      };
      renderWith(r);
      expect(screen.queryByTestId('title-mismatch')).toBeNull();
    });

    test('matching titles raise nothing', () => {
      renderWith(response());
      expect(screen.queryByTestId('title-mismatch')).toBeNull();
    });

    // Across encodings a "Remastered" suffix is routine, not a mislabel.
    test('an acoustic group with different titles raises nothing', () => {
      const r = www();
      r.groups[0] = { ...r.groups[0], tier: 'acoustic', worst_bit_error_rate: 0.04 };
      renderWith(r);
      expect(screen.queryByTestId('title-mismatch')).toBeNull();
    });

    // Unless the resolver found different songs on one album: Savant's Mortals
    // held one recording as 16 tracks, each cut to its own song's length (#6169).
    test('an acoustic group the resolver found to be different songs says so', () => {
      const r = www();
      r.groups[0] = { ...r.groups[0], tier: 'acoustic', worst_bit_error_rate: 0, class: 'mismatch' };
      renderWith(r);
      const notice = text(screen.getByTestId('title-mismatch'));
      expect(notice).toContain('The music is the same, but the copies are titled “WWW” and “WWW (instrumental)”');
      expect(notice).toContain("If you can't tell, get the album again");
    });
  });

  // One recording in several of an album's slots (#6184). A merge would keep
  // one title whether or not it is the audio's and fetch nothing, so it is not
  // offered: the operator says which song it is, or that they can't tell.
  describe('one recording in several slots', () => {
    function slots() {
      const r = response();
      r.groups[0] = {
        ...r.groups[0],
        tier: 'acoustic',
        worst_bit_error_rate: 0.04,
        class: 'mismatch',
        members: [member('www-01'), member('www-02', { title: 'WWW (instrumental)' })]
      };
      return r;
    }

    test('offers Get it again instead of Merge, with no copy proposed', () => {
      renderWith(slots());
      expect(screen.queryByRole('button', { name: 'Merge…' })).toBeNull();
      expect(screen.getByRole('button', { name: 'Get it again…' })).toBeTruthy();
      expect(screen.getAllByRole('radio').some((r) => (r as HTMLInputElement).checked)).toBe(false);
      expect(screen.queryByTestId('survivor-badge')).toBeNull();
    });

    test("can't tell: every copy goes, after a second click", async () => {
      renderWith(slots());
      await fireEvent.click(screen.getByRole('button', { name: 'Get it again…' }));
      expect(refetchDuplicateGroup).not.toHaveBeenCalled();
      const confirm = text(screen.getByTestId('refetch-confirm'));
      expect(confirm).toContain('All 2 copies will be deleted from disk');
      expect(confirm).toContain('the album is fetched again from another one');

      await fireEvent.click(screen.getByRole('button', { name: 'Remove 2 files and get it again' }));
      expect(refetchDuplicateGroup).toHaveBeenCalledWith('g-1', { keep_track_id: '' });
    });

    test('naming the song keeps that copy and removes the others', async () => {
      renderWith(slots());
      await fireEvent.click(screen.getByRole('radio', { name: /This is WWW \(instrumental\)/ }));
      expect(screen.getByTestId('song-badge')).toBeTruthy();
      await fireEvent.click(screen.getByRole('button', { name: 'Keep “WWW (instrumental)”…' }));
      expect(text(screen.getByTestId('refetch-confirm'))).toContain(
        'The copy titled “WWW (instrumental)” stays, and 1 copy under other titles will be deleted from disk'
      );
      await fireEvent.click(screen.getByRole('button', { name: 'Remove 1 file and get it again' }));
      expect(refetchDuplicateGroup).toHaveBeenCalledWith('g-1', { keep_track_id: 'www-02' });
    });

    test("I can't tell takes the pick back", async () => {
      renderWith(slots());
      await fireEvent.click(screen.getAllByRole('radio')[0]);
      await fireEvent.click(screen.getByRole('button', { name: "I can't tell which song it is" }));
      expect(screen.getByRole('button', { name: 'Get it again…' })).toBeTruthy();
      expect(screen.queryByTestId('song-badge')).toBeNull();
    });
  });

  // Three states all show zero groups. Each must say which it is.
  test('empty while still fingerprinting says so', () => {
    renderWith(
      response({
        groups: [],
        total: 0,
        fingerprints: { total: 1200, fingerprinted: 0, rejected: 0, pending: 1200, enabled: true }
      })
    );
    expect(text(screen.getByTestId('empty-state'))).toContain('still being fingerprinted');
  });

  // Switched off, the backlog never shrinks. "Still being fingerprinted" would
  // promise work nothing is doing (#3913).
  test('with fingerprinting off the page says so instead of promising progress', () => {
    renderWith(
      response({
        groups: [],
        total: 0,
        fingerprints: { total: 1200, fingerprinted: 0, rejected: 0, pending: 1200, enabled: false }
      })
    );
    const empty = text(screen.getByTestId('empty-state'));
    expect(empty).toContain('Fingerprinting is off');
    expect(empty).not.toContain('still being fingerprinted');
    expect(text(screen.getByTestId('sweep-status'))).toContain('Fingerprinting is off');
  });

  test('the fingerprinting settings are a link to Library, saying whether it is on', () => {
    renderWith(response());
    const line = screen.getByTestId('fingerprint-settings-link');
    expect(text(line)).toContain('Fingerprinting is on');
    expect(line.querySelector('a')?.getAttribute('href')).toBe('/admin/library#fingerprints');
  });

  test('empty before any sweep says the sweep has not run', () => {
    renderWith(
      response({
        groups: [],
        total: 0,
        sweep: { ...finishedSweep, state: 'never', started_at: null, finished_at: null, candidates: null }
      })
    );
    expect(text(screen.getByTestId('empty-state'))).toContain("hasn't run yet");
  });

  test('empty after a sweep says nothing needs review', () => {
    renderWith(response({ groups: [], total: 0 }));
    expect(text(screen.getByTestId('empty-state'))).toContain('Nothing needs review');
  });

  test('Not duplicates dismisses that group', async () => {
    renderWith(response());
    await fireEvent.click(screen.getByRole('button', { name: 'Not duplicates' }));
    expect(dismissDuplicateGroup).toHaveBeenCalledWith('g-1');
  });

  test('Sweep now starts a sweep', async () => {
    renderWith(response());
    await fireEvent.click(screen.getByRole('button', { name: 'Sweep now' }));
    expect(runDuplicateSweep).toHaveBeenCalledTimes(1);
  });

  // A merge deletes files. The first click must only arm it.
  test('Merge needs a second click, and keeps the proposed copy by default', async () => {
    renderWith(response());
    await fireEvent.click(screen.getByRole('button', { name: 'Merge…' }));
    expect(mergeDuplicateGroup).not.toHaveBeenCalled();
    expect(text(screen.getByTestId('merge-confirm'))).toContain('The other 1 file will be deleted from disk');

    await fireEvent.click(screen.getByRole('button', { name: 'Remove 1 file and merge' }));
    expect(mergeDuplicateGroup).toHaveBeenCalledWith('g-1', { survivor_track_id: 'www-01' });
  });

  test('choosing another copy to keep sends that copy', async () => {
    renderWith(response());
    const radios = screen.getAllByRole('radio');
    expect((radios[0] as HTMLInputElement).checked).toBe(true);
    await fireEvent.click(radios[1]);

    await fireEvent.click(screen.getByRole('button', { name: 'Merge…' }));
    await fireEvent.click(screen.getByRole('button', { name: 'Remove 1 file and merge' }));
    expect(mergeDuplicateGroup).toHaveBeenCalledWith('g-1', { survivor_track_id: 'www-02' });
  });

  test('Cancel disarms the merge', async () => {
    renderWith(response());
    await fireEvent.click(screen.getByRole('button', { name: 'Merge…' }));
    await fireEvent.click(screen.getByRole('button', { name: 'Cancel' }));
    expect(screen.queryByTestId('merge-confirm')).toBeNull();
    expect(screen.getByRole('button', { name: 'Merge…' })).toBeTruthy();
  });

  // M498: the resolver's three outcomes are three tabs, each with its size.
  describe('tabs', () => {
    test('each tab shows its count, and Across releases asks for that view', async () => {
      renderWith(response());
      expect(screen.getByRole('tab', { name: /needs review/i })).toHaveAttribute('aria-selected', 'true');
      expect(screen.getAllByTestId('tab-count').map(text)).toEqual(['1', '4', '2']);
      expect(createDuplicatesQuery).toHaveBeenLastCalledWith('review');

      await fireEvent.click(screen.getByRole('tab', { name: /across releases/i }));
      expect(createDuplicatesQuery).toHaveBeenLastCalledWith('cross_release');
    });

    // Copies across releases are linked as one song; dismissing one says they
    // are not, which is what the button names.
    test('Across releases dismisses as Not the same song', async () => {
      renderWith(response());
      await fireEvent.click(screen.getByRole('tab', { name: /across releases/i }));
      await fireEvent.click(screen.getByRole('button', { name: 'Not the same song' }));
      expect(dismissDuplicateGroup).toHaveBeenCalledWith('g-1');
    });

    test('Resolved automatically lists the merges the resolver made', async () => {
      renderWith(response(), [
        {
          id: 'a-1',
          action: 'duplicate_merge',
          created_at: ago(HOUR),
          details: {
            survivor_path: '/music/Gorillaz/Humanz (2017)/03 - Saturnz Barz.mp3',
            survivor_reason: 'the copy that is not a video rip',
            removed: [{ track_id: 't-2', file_path: '/music/Gorillaz/Humanz (2017)/03 - Saturnz Barz (Official Video).mp3' }]
          }
        }
      ]);
      await fireEvent.click(screen.getByRole('tab', { name: /resolved automatically/i }));
      const items = screen.getAllByTestId('resolved-item').map(text);
      expect(items[0]).toContain('Kept 03 - Saturnz Barz.mp3 (the copy that is not a video rip) and removed 1 file.');
      expect(screen.queryByTestId('duplicate-group')).toBeNull();
    });

    test('Resolved automatically says what was dismissed and which slots were emptied', async () => {
      renderWith(response(), [
        {
          id: 'a-2',
          action: 'duplicate_dismiss',
          created_at: ago(HOUR),
          details: { artist: 'Moe Shop', titles: ['Lovesick', 'Lovesick (Instrumental)'] }
        },
        {
          id: 'a-3',
          action: 'duplicate_wrong_file',
          created_at: ago(HOUR),
          details: {
            artist: 'Savant',
            kept_title: 'Void',
            removed: [{ track_id: 't-9', file_path: '/data/Music/Savant/Void/17 - Reach.m4a', title: 'Reach' }]
          }
        },
        {
          id: 'a-4',
          action: 'duplicate_wrong_file',
          created_at: ago(HOUR),
          details: {
            artist: 'Shnabubula',
            removed: [
              { track_id: 't-5', file_path: '/data/Music/Shnabubula/05 - Fading Light.mp3', title: 'Fading Light' },
              { track_id: 't-10', file_path: '/data/Music/Shnabubula/10 - Looking for Answers.mp3', title: 'Looking for Answers' }
            ]
          }
        }
      ]);
      await fireEvent.click(screen.getByRole('tab', { name: /resolved automatically/i }));
      const items = screen.getAllByTestId('resolved-item').map(text);
      expect(items[0]).toContain('Moe Shop: Lovesick and Lovesick (Instrumental) are different versions, not duplicates. Both kept.');
      expect(items[1]).toContain(
        'Savant: the recording of Void was also filed as Reach. Removed from there; the album will be fetched again.'
      );
      expect(items[1]).toContain('/data/Music/Savant/Void/17 - Reach.m4a');
      expect(items[2]).toContain(
        'Shnabubula: one recording was filed as Fading Light and Looking for Answers, and it is none of them. Removed; the album will be fetched again.'
      );
    });
  });

  describe("the resolver's note", () => {
    test('shows above the group it explains', () => {
      const r = response();
      r.groups[0] = { ...r.groups[0], resolve_note: 'Identical audio filed under different titles.' };
      renderWith(r);
      expect(text(screen.getByTestId('resolve-note'))).toBe('Identical audio filed under different titles.');
    });

    test('a merge confirms and sends the copy chosen to keep', async () => {
      renderWith(response());
      await fireEvent.click(screen.getAllByRole('radio')[1]);
      await fireEvent.click(screen.getByRole('button', { name: 'Merge…' }));
      await fireEvent.click(screen.getByRole('button', { name: 'Remove 1 file and merge' }));
      expect(mergeDuplicateGroup).toHaveBeenCalledWith('g-1', { survivor_track_id: 'www-02' });
    });
  });
});