/**
 * Phase 5b — transfer event recording tests.
 *
 * Follows the same injectable-parameter pattern as claimEvents.test.js:
 *   _TicketModel  — controls the DB layer (updateOne)
 *   _recordAction — captures recording calls without any module mocking
 *
 * No vi.mock needed; all dependencies injected directly.
 *
 * Tests applyTransfer directly (same pattern as testing applyClaim directly).
 *
 * Covers:
 *   (a) transfer to different member — one 'transfer' event with fromId/toId
 *   (b) transfer to current claimer  — fromId === toId → no event
 *   (c) fromId/toId/staffId/guildId correctness
 */
import { describe, it, expect, vi } from 'vitest';

import { applyTransfer } from '../handlers/commands/index.js';

// ---------------------------------------------------------------------------
// Shared factories
// ---------------------------------------------------------------------------

function makeTicket(overrides = {}) {
  return {
    gmailThreadId:  'discord-test-001',
    escalationTier: 0,
    escalated:      false,
    claimerId:      'prev-claimer-001',
    claimedBy:      'PrevClaimerName',
    priority:       'normal',
    game:           'TestGame',
    senderEmail:    'user@example.com',
    creatorId:      'creator-001',
    ticketNumber:   42,
    ...overrides
  };
}

function makeGuildMember(userId = 'new-claimer-002') {
  return {
    id:          userId,
    displayName: 'New Claimer',
    user: {
      id:       userId,
      username: 'newclaimer',
      tag:      'newclaimer#0002',
      toString: () => `<@${userId}>`
    }
  };
}

function makeInteraction(userId = 'staff-001') {
  return {
    user: {
      id:       userId,
      username: 'staffuser',
      tag:      'staffuser#0001',
      toString: () => `<@${userId}>`
    },
    member: { displayName: 'Staff Member' },
    guild: {
      id: 'guild-001',
      members: {
        fetch: vi.fn().mockRejectedValue(new Error('no member in test env'))
      }
    },
    channel: {
      id:       'chan-001',
      name:     'ticket-chan-001',
      isThread: vi.fn().mockReturnValue(true),
      send:     vi.fn().mockResolvedValue({ id: 'sent-msg-001' })
    },
    editReply:  vi.fn().mockResolvedValue(undefined),
    client: {
      channels: { fetch: vi.fn().mockResolvedValue(null) }
    }
  };
}

// ---------------------------------------------------------------------------
// (a) Transfer to a different member — one event
// ---------------------------------------------------------------------------

describe('applyTransfer — different member emits one event', () => {
  it('emits exactly one "transfer" event', async () => {
    const ticket       = makeTicket({ claimerId: 'prev-claimer-001' });
    const guildMember  = makeGuildMember('new-claimer-002');
    const mockUpdateOne = vi.fn().mockResolvedValue({ modifiedCount: 1 });
    const mockRecord   = vi.fn();
    const interaction  = makeInteraction('staff-001');

    await applyTransfer(interaction, ticket, guildMember, 'reason', { updateOne: mockUpdateOne }, mockRecord);

    expect(mockRecord).toHaveBeenCalledTimes(1);
    const [staffId, type] = mockRecord.mock.calls[0];
    expect(staffId).toBe('staff-001');
    expect(type).toBe('transfer');
  });

  it('passes correct fromId, toId, guildId, and ticket', async () => {
    const ticket       = makeTicket({ claimerId: 'prev-claimer-001' });
    const guildMember  = makeGuildMember('new-claimer-002');
    const mockUpdateOne = vi.fn().mockResolvedValue({ modifiedCount: 1 });
    const mockRecord   = vi.fn();
    const interaction  = makeInteraction('staff-001');

    await applyTransfer(interaction, ticket, guildMember, 'reason', { updateOne: mockUpdateOne }, mockRecord);

    const [, , payload] = mockRecord.mock.calls[0];
    expect(payload.fromId).toBe('prev-claimer-001');
    expect(payload.toId).toBe('new-claimer-002');
    expect(payload.guildId).toBe('guild-001');
    expect(payload.ticket).toBe(ticket);
  });

  it('fromId is the pre-write claimerId (captured before the DB write)', async () => {
    const ticket       = makeTicket({ claimerId: 'original-claimer' });
    const guildMember  = makeGuildMember('new-staff-003');
    const mockUpdateOne = vi.fn().mockResolvedValue({ modifiedCount: 1 });
    const mockRecord   = vi.fn();
    const interaction  = makeInteraction('staff-001');

    await applyTransfer(interaction, ticket, guildMember, 'reason', { updateOne: mockUpdateOne }, mockRecord);

    const [, , payload] = mockRecord.mock.calls[0];
    expect(payload.fromId).toBe('original-claimer');
    expect(payload.toId).toBe('new-staff-003');
  });
});

// ---------------------------------------------------------------------------
// (b) Transfer to the current claimer — no event
// ---------------------------------------------------------------------------

describe('applyTransfer — transfer to current claimer emits no event', () => {
  it('emits no event when fromId === toId (transferring to existing claimer)', async () => {
    const ticket       = makeTicket({ claimerId: 'same-claimer-001' });
    const guildMember  = makeGuildMember('same-claimer-001');
    const mockUpdateOne = vi.fn().mockResolvedValue({ modifiedCount: 1 });
    const mockRecord   = vi.fn();
    const interaction  = makeInteraction('staff-001');

    await applyTransfer(interaction, ticket, guildMember, 'reason', { updateOne: mockUpdateOne }, mockRecord);

    expect(mockRecord).not.toHaveBeenCalled();
  });

  it('emits one event when the ticket is unclaimed (fromId null) and toId is non-null — null !== toId satisfies the fromId !== toId gate', async () => {
    // null !== 'new-claimer' so this IS a real transfer — event IS emitted
    const ticket       = makeTicket({ claimerId: null });
    const guildMember  = makeGuildMember('new-claimer-002');
    const mockUpdateOne = vi.fn().mockResolvedValue({ modifiedCount: 1 });
    const mockRecord   = vi.fn();
    const interaction  = makeInteraction('staff-001');

    await applyTransfer(interaction, ticket, guildMember, 'reason', { updateOne: mockUpdateOne }, mockRecord);

    // null !== 'new-claimer-002' → event IS emitted
    expect(mockRecord).toHaveBeenCalledTimes(1);
    const [, , payload] = mockRecord.mock.calls[0];
    expect(payload.fromId).toBeNull();
    expect(payload.toId).toBe('new-claimer-002');
  });
});