import { describe, it } from 'node:test';
import assert from 'node:assert/strict';
import {
  getMutedThreads,
  getThreadNotificationMode,
  pruneThreadNotifications,
  shouldNotifyThreadReply,
  ThreadDefaultBehavior,
  ThreadNotificationMode,
  ThreadNotificationsContent,
  ThreadNotifyDecision,
} from './threadNotifications';

const DAY = 24 * 60 * 60 * 1000;

const decide = (
  overrides: Partial<Parameters<typeof shouldNotifyThreadReply>[0]>,
): ThreadNotifyDecision =>
  shouldNotifyThreadReply({
    mode: ThreadNotificationMode.Default,
    defaultBehavior: 'participating',
    participated: false,
    highlight: false,
    notify: false,
    roomMuted: false,
    ...overrides,
  });

describe('shouldNotifyThreadReply', () => {
  it('roomMuted trumps everything, even mode All + highlight', () => {
    assert.equal(
      decide({ roomMuted: true, mode: ThreadNotificationMode.All, highlight: true }),
      'none',
    );
  });

  it('roomMuted trumps Default + participating + participated', () => {
    assert.equal(decide({ roomMuted: true, participated: true }), 'none');
  });

  it('mode Mute is none regardless of highlight/participation', () => {
    assert.equal(
      decide({ mode: ThreadNotificationMode.Mute, highlight: true, participated: true }),
      'none',
    );
  });

  it('mode All + highlight => loud', () => {
    assert.equal(decide({ mode: ThreadNotificationMode.All, highlight: true }), 'loud');
  });

  it('mode All + no highlight => notify', () => {
    assert.equal(decide({ mode: ThreadNotificationMode.All, highlight: false }), 'notify');
  });

  it('mode MentionsOnly + highlight => loud', () => {
    assert.equal(decide({ mode: ThreadNotificationMode.MentionsOnly, highlight: true }), 'loud');
  });

  it('mode MentionsOnly + no highlight => none (even if participated)', () => {
    assert.equal(
      decide({ mode: ThreadNotificationMode.MentionsOnly, highlight: false, participated: true }),
      'none',
    );
  });

  it('Default + behavior all + highlight => loud', () => {
    assert.equal(decide({ defaultBehavior: 'all', highlight: true }), 'loud');
  });

  it('Default + behavior all + no highlight => notify', () => {
    assert.equal(decide({ defaultBehavior: 'all', highlight: false }), 'notify');
  });

  it('Default + participating + highlight => loud (even if not participated)', () => {
    assert.equal(
      decide({ defaultBehavior: 'participating', highlight: true, participated: false }),
      'loud',
    );
  });

  it('Default + participating + no highlight + participated => notify', () => {
    assert.equal(
      decide({ defaultBehavior: 'participating', highlight: false, participated: true }),
      'notify',
    );
  });

  it('Default + participating + no highlight + not participated => none', () => {
    assert.equal(
      decide({ defaultBehavior: 'participating', highlight: false, participated: false }),
      'none',
    );
  });

  it('ignores the `notify` input entirely in v1', () => {
    // notify=true must not upgrade a "none" decision.
    assert.equal(
      decide({ defaultBehavior: 'participating', participated: false, notify: true }),
      'none',
    );
    // notify=false must not downgrade an "all" mode notify.
    assert.equal(decide({ mode: ThreadNotificationMode.All, notify: false }), 'notify');
  });
});

describe('getThreadNotificationMode', () => {
  it('returns Default for undefined content', () => {
    assert.equal(getThreadNotificationMode(undefined, '!r', '$t'), ThreadNotificationMode.Default);
  });

  it('returns Default when room or thread is absent', () => {
    const content: ThreadNotificationsContent = {
      rooms: { '!r': { $other: { mode: ThreadNotificationMode.All, ts: 1 } } },
    };
    assert.equal(getThreadNotificationMode(content, '!r', '$t'), ThreadNotificationMode.Default);
    assert.equal(getThreadNotificationMode(content, '!x', '$t'), ThreadNotificationMode.Default);
  });

  it('returns the stored mode', () => {
    const content: ThreadNotificationsContent = {
      rooms: { '!r': { $t: { mode: ThreadNotificationMode.Mute, ts: 1 } } },
    };
    assert.equal(getThreadNotificationMode(content, '!r', '$t'), ThreadNotificationMode.Mute);
  });

  it('is safe against malformed entries', () => {
    const bad = {
      rooms: {
        '!r': {
          $badMode: { mode: 'nonsense', ts: 1 },
          $noTs: { mode: ThreadNotificationMode.All },
          $notObj: 'oops',
          $nullEntry: null,
        },
      },
    } as unknown as ThreadNotificationsContent;
    assert.equal(getThreadNotificationMode(bad, '!r', '$badMode'), ThreadNotificationMode.Default);
    assert.equal(getThreadNotificationMode(bad, '!r', '$noTs'), ThreadNotificationMode.Default);
    assert.equal(getThreadNotificationMode(bad, '!r', '$notObj'), ThreadNotificationMode.Default);
    assert.equal(
      getThreadNotificationMode(bad, '!r', '$nullEntry'),
      ThreadNotificationMode.Default,
    );
  });

  it('is safe when rooms is not an object', () => {
    const bad = { rooms: 'oops' } as unknown as ThreadNotificationsContent;
    assert.equal(getThreadNotificationMode(bad, '!r', '$t'), ThreadNotificationMode.Default);
  });
});

describe('getMutedThreads', () => {
  it('returns empty set for undefined/absent room', () => {
    assert.deepEqual(getMutedThreads(undefined, '!r'), new Set());
    assert.deepEqual(getMutedThreads({ rooms: {} }, '!r'), new Set());
  });

  it('collects only Mute entries', () => {
    const content: ThreadNotificationsContent = {
      rooms: {
        '!r': {
          $a: { mode: ThreadNotificationMode.Mute, ts: 1 },
          $b: { mode: ThreadNotificationMode.All, ts: 1 },
          $c: { mode: ThreadNotificationMode.Mute, ts: 1 },
        },
      },
    };
    assert.deepEqual(getMutedThreads(content, '!r'), new Set(['$a', '$c']));
  });

  it('ignores malformed entries', () => {
    const bad = {
      rooms: { '!r': { $a: { mode: 'mute-ish', ts: 1 }, $b: null } },
    } as unknown as ThreadNotificationsContent;
    assert.deepEqual(getMutedThreads(bad, '!r'), new Set());
  });
});

describe('pruneThreadNotifications', () => {
  const now = 1_000_000_000_000;

  it('drops rooms not in joinedRoomIds', () => {
    const content: ThreadNotificationsContent = {
      rooms: {
        '!keep': { $t: { mode: ThreadNotificationMode.All, ts: now } },
        '!left': { $t: { mode: ThreadNotificationMode.All, ts: now } },
      },
    };
    const out = pruneThreadNotifications(content, new Set(['!keep']), now);
    assert.deepEqual(Object.keys(out.rooms ?? {}), ['!keep']);
  });

  it('drops entries older than 180 days', () => {
    const content: ThreadNotificationsContent = {
      rooms: {
        '!r': {
          $fresh: { mode: ThreadNotificationMode.All, ts: now - 179 * DAY },
          $old: { mode: ThreadNotificationMode.All, ts: now - 181 * DAY },
        },
      },
    };
    const out = pruneThreadNotifications(content, new Set(['!r']), now);
    assert.deepEqual(Object.keys(out.rooms?.['!r'] ?? {}), ['$fresh']);
  });

  it('caps a room at 200 entries, evicting oldest ts first', () => {
    const entries: Record<string, { mode: ThreadNotificationMode.All; ts: number }> = {};
    // 205 entries, ts ascending with the id index.
    for (let i = 0; i < 205; i += 1) {
      entries[`$t${i}`] = { mode: ThreadNotificationMode.All, ts: now - (205 - i) * 1000 };
    }
    const content: ThreadNotificationsContent = { rooms: { '!r': entries } };
    const out = pruneThreadNotifications(content, new Set(['!r']), now);
    const kept = out.rooms?.['!r'] ?? {};
    assert.equal(Object.keys(kept).length, 200);
    // Oldest 5 ($t0..$t4) evicted; newest retained.
    assert.equal(kept.$t0, undefined);
    assert.equal(kept.$t4, undefined);
    assert.notEqual(kept.$t5, undefined);
    assert.notEqual(kept.$t204, undefined);
  });

  it('drops rooms left with no entries', () => {
    const content: ThreadNotificationsContent = {
      rooms: {
        '!r': { $old: { mode: ThreadNotificationMode.All, ts: now - 200 * DAY } },
      },
    };
    const out = pruneThreadNotifications(content, new Set(['!r']), now);
    assert.equal(out.rooms, undefined);
  });

  it('preserves the default behavior field', () => {
    const behavior: ThreadDefaultBehavior = 'all';
    const content: ThreadNotificationsContent = { default: behavior, rooms: {} };
    const out = pruneThreadNotifications(content, new Set(), now);
    assert.equal(out.default, 'all');
  });

  it('never mutates the input', () => {
    const content: ThreadNotificationsContent = {
      default: 'participating',
      rooms: {
        '!r': { $t: { mode: ThreadNotificationMode.All, ts: now } },
        '!left': { $t: { mode: ThreadNotificationMode.All, ts: now } },
      },
    };
    const snapshot = JSON.parse(JSON.stringify(content));
    const out = pruneThreadNotifications(content, new Set(['!r']), now);
    assert.deepEqual(content, snapshot);
    // Output room objects are fresh, not shared references with the input.
    assert.notEqual(out.rooms?.['!r'], content.rooms?.['!r']);
  });

  it('handles malformed rooms container safely', () => {
    const bad = { rooms: 'oops' } as unknown as ThreadNotificationsContent;
    assert.deepEqual(pruneThreadNotifications(bad, new Set(['!r']), now), {});
  });
});