/**
 * @sh-mcp/calendar — unit tests
 *
 * All tests inject a mock CalendarClient and a mock AuthContext.
 * No real network calls.  No AWS calls at import time.
 *
 * Covers:
 *  - happy path for each tool
 *  - empty result
 *  - API error propagation
 *  - throttle / retryable error path
 *  - scope enforcement (missing scope → ScopeError)
 *  - external-attendee flagging on create_calendar_event
 */

import { describe, it, expect, vi, beforeEach } from 'vitest';
import type { AuthContext } from '@sh-mcp/shared';
import { buildCalendarTools } from '../src/tools.js';
import type { CalendarClient, CalendarEvent, AvailabilityResult } from '../src/client.js';
import { CalendarClientError } from '../src/client.js';

// ---------------------------------------------------------------------------
// Fixtures
// ---------------------------------------------------------------------------

const MOCK_CTX: AuthContext = {
  sub: 'lauren@seahavenind.com',
  scopes: ['ops:read', 'ops:tasks', 'gmail:self', 'calendar:self'],
  aud: 'sh-mcp-ops',
};

const CTX_NO_CALENDAR: AuthContext = {
  sub: 'other@seahavenind.com',
  scopes: ['ops:read'],
  aud: 'sh-mcp-ops',
};

const INTERNAL_EVENT: CalendarEvent = {
  id: 'event-001',
  summary: 'Team standup',
  start: '2026-06-11T09:00:00-04:00',
  end: '2026-06-11T09:15:00-04:00',
  attendees: [
    { email: 'lauren@seahavenind.com', self: true, responseStatus: 'accepted' },
    { email: 'adam@seahavenind.com', responseStatus: 'accepted' },
  ],
  status: 'confirmed',
};

const EXTERNAL_EVENT: CalendarEvent = {
  id: 'event-002',
  summary: 'Vendor call',
  start: '2026-06-11T14:00:00-04:00',
  end: '2026-06-11T15:00:00-04:00',
  attendees: [
    { email: 'lauren@seahavenind.com', self: true, responseStatus: 'accepted' },
    { email: 'vendor@externalco.com', responseStatus: 'needsAction' },
  ],
  status: 'confirmed',
};

const AVAILABILITY: AvailabilityResult = {
  busy: [{ start: '2026-06-11T09:00:00Z', end: '2026-06-11T09:15:00Z' }],
  free: [
    { start: '2026-06-11T08:00:00Z', end: '2026-06-11T09:00:00Z' },
    { start: '2026-06-11T09:15:00Z', end: '2026-06-11T17:00:00Z' },
  ],
};

// ---------------------------------------------------------------------------
// Mock client builder
// ---------------------------------------------------------------------------

function buildMockClient(overrides: Partial<CalendarClient> = {}): CalendarClient {
  return {
    getEvents: vi.fn().mockResolvedValue([INTERNAL_EVENT]),
    checkAvailability: vi.fn().mockResolvedValue(AVAILABILITY),
    createEvent: vi.fn().mockResolvedValue(INTERNAL_EVENT),
    ...overrides,
  };
}

// ---------------------------------------------------------------------------
// get_calendar_events
// ---------------------------------------------------------------------------

describe('get_calendar_events', () => {
  let mockClient: CalendarClient;
  let tools: ReturnType<typeof buildCalendarTools>;

  beforeEach(() => {
    mockClient = buildMockClient();
    tools = buildCalendarTools(mockClient);
  });

  const getTool = (ts: ReturnType<typeof buildCalendarTools>) =>
    ts.find((t) => t.name === 'get_calendar_events')!;

  it('happy path — returns events with count', async () => {
    const tool = getTool(tools);
    const result = await tool.handler(
      { timeMin: '2026-06-11T00:00:00Z', timeMax: '2026-06-11T23:59:59Z' },
      MOCK_CTX,
    );
    expect(result.count).toBe(1);
    expect(result.events[0].id).toBe('event-001');
    expect(mockClient.getEvents).toHaveBeenCalledWith(
      MOCK_CTX.sub,
      expect.objectContaining({
        timeMin: '2026-06-11T00:00:00Z',
        timeMax: '2026-06-11T23:59:59Z',
        singleEvents: true,
        orderBy: 'startTime',
      }),
    );
  });

  it('empty result — returns count 0', async () => {
    mockClient = buildMockClient({ getEvents: vi.fn().mockResolvedValue([]) });
    tools = buildCalendarTools(mockClient);
    const result = await getTool(tools).handler(
      { timeMin: '2026-06-12T00:00:00Z', timeMax: '2026-06-12T23:59:59Z' },
      MOCK_CTX,
    );
    expect(result.count).toBe(0);
    expect(result.events).toHaveLength(0);
  });

  it('non-retryable API error is re-thrown as-is', async () => {
    mockClient = buildMockClient({
      getEvents: vi.fn().mockRejectedValue(
        new CalendarClientError('Forbidden', 403, false),
      ),
    });
    tools = buildCalendarTools(mockClient);
    await expect(
      getTool(tools).handler(
        { timeMin: '2026-06-11T00:00:00Z', timeMax: '2026-06-11T23:59:59Z' },
        MOCK_CTX,
      ),
    ).rejects.toThrow('Forbidden');
  });

  it('retryable/throttle error is wrapped with user-friendly message', async () => {
    mockClient = buildMockClient({
      getEvents: vi.fn().mockRejectedValue(
        new CalendarClientError('Rate limited', 429, true),
      ),
    });
    tools = buildCalendarTools(mockClient);
    await expect(
      getTool(tools).handler(
        { timeMin: '2026-06-11T00:00:00Z', timeMax: '2026-06-11T23:59:59Z' },
        MOCK_CTX,
      ),
    ).rejects.toThrow(/temporarily unavailable.*retryable/i);
  });

  it('missing calendar:self scope throws ScopeError', async () => {
    await expect(
      getTool(tools).handler(
        { timeMin: '2026-06-11T00:00:00Z', timeMax: '2026-06-11T23:59:59Z' },
        CTX_NO_CALENDAR,
      ),
    ).rejects.toThrow();
    // getEvents should never have been called
    expect(mockClient.getEvents).not.toHaveBeenCalled();
  });

  it('flags external attendees on returned events', async () => {
    mockClient = buildMockClient({
      getEvents: vi.fn().mockResolvedValue([EXTERNAL_EVENT]),
    });
    tools = buildCalendarTools(mockClient);
    const result = await getTool(tools).handler(
      { timeMin: '2026-06-11T00:00:00Z', timeMax: '2026-06-11T23:59:59Z' },
      MOCK_CTX,
    );
    expect(result.events[0].hasExternalAttendees).toBe(true);
    expect((result.events[0] as { externalAttendeeWarning?: string }).externalAttendeeWarning)
      .toContain('vendor@externalco.com');
  });

  it('defines correct tool metadata', () => {
    const tool = getTool(tools);
    expect(tool.name).toBe('get_calendar_events');
    expect(tool.tier).toBe('ops');
    expect(tool.requiredScope).toBe('calendar:self');
  });
});

// ---------------------------------------------------------------------------
// check_availability
// ---------------------------------------------------------------------------

describe('check_availability', () => {
  let mockClient: CalendarClient;
  let tools: ReturnType<typeof buildCalendarTools>;

  beforeEach(() => {
    mockClient = buildMockClient();
    tools = buildCalendarTools(mockClient);
  });

  const getTool = (ts: ReturnType<typeof buildCalendarTools>) =>
    ts.find((t) => t.name === 'check_availability')!;

  it('happy path — returns busy and free blocks with echoed window', async () => {
    const input = {
      timeMin: '2026-06-11T08:00:00Z',
      timeMax: '2026-06-11T17:00:00Z',
    };
    const result = await getTool(tools).handler(input, MOCK_CTX);
    expect(result.busy).toHaveLength(1);
    expect(result.free).toHaveLength(2);
    expect(result.timeMin).toBe(input.timeMin);
    expect(result.timeMax).toBe(input.timeMax);
  });

  it('empty availability — no busy blocks', async () => {
    mockClient = buildMockClient({
      checkAvailability: vi.fn().mockResolvedValue({ busy: [], free: [
        { start: '2026-06-11T08:00:00Z', end: '2026-06-11T17:00:00Z' },
      ] }),
    });
    tools = buildCalendarTools(mockClient);
    const result = await getTool(tools).handler(
      { timeMin: '2026-06-11T08:00:00Z', timeMax: '2026-06-11T17:00:00Z' },
      MOCK_CTX,
    );
    expect(result.busy).toHaveLength(0);
    expect(result.free).toHaveLength(1);
  });

  it('non-retryable error is re-thrown', async () => {
    mockClient = buildMockClient({
      checkAvailability: vi.fn().mockRejectedValue(
        new CalendarClientError('Not found', 404, false),
      ),
    });
    tools = buildCalendarTools(mockClient);
    await expect(
      getTool(tools).handler(
        { timeMin: '2026-06-11T08:00:00Z', timeMax: '2026-06-11T17:00:00Z' },
        MOCK_CTX,
      ),
    ).rejects.toThrow('Not found');
  });

  it('throttle/retryable error wraps with user-friendly message', async () => {
    mockClient = buildMockClient({
      checkAvailability: vi.fn().mockRejectedValue(
        new CalendarClientError('Quota exceeded', 429, true),
      ),
    });
    tools = buildCalendarTools(mockClient);
    await expect(
      getTool(tools).handler(
        { timeMin: '2026-06-11T08:00:00Z', timeMax: '2026-06-11T17:00:00Z' },
        MOCK_CTX,
      ),
    ).rejects.toThrow(/temporarily unavailable.*retryable/i);
  });

  it('missing calendar:self scope throws before calling client', async () => {
    await expect(
      getTool(tools).handler(
        { timeMin: '2026-06-11T08:00:00Z', timeMax: '2026-06-11T17:00:00Z' },
        CTX_NO_CALENDAR,
      ),
    ).rejects.toThrow();
    expect(mockClient.checkAvailability).not.toHaveBeenCalled();
  });

  it('defines correct tool metadata', () => {
    const tool = getTool(tools);
    expect(tool.name).toBe('check_availability');
    expect(tool.tier).toBe('ops');
    expect(tool.requiredScope).toBe('calendar:self');
  });
});

// ---------------------------------------------------------------------------
// create_calendar_event
// ---------------------------------------------------------------------------

describe('create_calendar_event', () => {
  let mockClient: CalendarClient;
  let tools: ReturnType<typeof buildCalendarTools>;

  beforeEach(() => {
    mockClient = buildMockClient();
    tools = buildCalendarTools(mockClient);
  });

  const getTool = (ts: ReturnType<typeof buildCalendarTools>) =>
    ts.find((t) => t.name === 'create_calendar_event')!;

  it('happy path — internal attendees only, hasExternalAttendees=false', async () => {
    const input = {
      summary: 'Sprint planning',
      start: '2026-06-15T10:00:00-04:00',
      end: '2026-06-15T11:00:00-04:00',
      attendees: [{ email: 'adam@seahavenind.com' }],
    };
    const result = await getTool(tools).handler(input, MOCK_CTX);
    expect(result.id).toBe('event-001');
    expect(result.hasExternalAttendees).toBe(false);
    expect((result as { externalAttendeeWarning?: string }).externalAttendeeWarning).toBeUndefined();
    expect(mockClient.createEvent).toHaveBeenCalledWith(
      MOCK_CTX.sub,
      expect.objectContaining({ summary: 'Sprint planning' }),
    );
  });

  it('external attendee — hasExternalAttendees=true with warning', async () => {
    mockClient = buildMockClient({
      createEvent: vi.fn().mockResolvedValue(EXTERNAL_EVENT),
    });
    tools = buildCalendarTools(mockClient);
    const input = {
      summary: 'Vendor call',
      start: '2026-06-11T14:00:00-04:00',
      end: '2026-06-11T15:00:00-04:00',
      attendees: [
        { email: 'lauren@seahavenind.com' },
        { email: 'vendor@externalco.com' },
      ],
    };
    const result = await getTool(tools).handler(input, MOCK_CTX);
    expect(result.hasExternalAttendees).toBe(true);
    expect(result.externalAttendeeWarning).toContain('vendor@externalco.com');
    expect(result.externalAttendeeWarning).toContain('seahavenind.com');
  });

  it('non-retryable error is re-thrown', async () => {
    mockClient = buildMockClient({
      createEvent: vi.fn().mockRejectedValue(
        new CalendarClientError('Conflict', 409, false),
      ),
    });
    tools = buildCalendarTools(mockClient);
    await expect(
      getTool(tools).handler(
        { summary: 'Test', start: '2026-06-11T10:00:00Z', end: '2026-06-11T11:00:00Z' },
        MOCK_CTX,
      ),
    ).rejects.toThrow('Conflict');
  });

  it('throttle/retryable error wraps with user-friendly message', async () => {
    mockClient = buildMockClient({
      createEvent: vi.fn().mockRejectedValue(
        new CalendarClientError('Rate limited', 429, true),
      ),
    });
    tools = buildCalendarTools(mockClient);
    await expect(
      getTool(tools).handler(
        { summary: 'Test', start: '2026-06-11T10:00:00Z', end: '2026-06-11T11:00:00Z' },
        MOCK_CTX,
      ),
    ).rejects.toThrow(/temporarily unavailable.*retryable/i);
  });

  it('missing calendar:self scope throws before calling client', async () => {
    await expect(
      getTool(tools).handler(
        { summary: 'Test', start: '2026-06-11T10:00:00Z', end: '2026-06-11T11:00:00Z' },
        CTX_NO_CALENDAR,
      ),
    ).rejects.toThrow();
    expect(mockClient.createEvent).not.toHaveBeenCalled();
  });

  it('event with no attendees — hasExternalAttendees=false', async () => {
    mockClient = buildMockClient({
      createEvent: vi.fn().mockResolvedValue({
        ...INTERNAL_EVENT,
        attendees: [],
      }),
    });
    tools = buildCalendarTools(mockClient);
    const result = await getTool(tools).handler(
      { summary: 'Solo block', start: '2026-06-11T13:00:00Z', end: '2026-06-11T14:00:00Z' },
      MOCK_CTX,
    );
    expect(result.hasExternalAttendees).toBe(false);
  });

  it('defines correct tool metadata', () => {
    const tool = getTool(tools);
    expect(tool.name).toBe('create_calendar_event');
    expect(tool.tier).toBe('ops');
    expect(tool.requiredScope).toBe('calendar:self');
  });
});

// ---------------------------------------------------------------------------
// Index / registry shape
// ---------------------------------------------------------------------------

describe('buildCalendarTools registry', () => {
  it('returns exactly 3 tools with distinct names', () => {
    const mockClient = buildMockClient();
    const tools = buildCalendarTools(mockClient);
    expect(tools).toHaveLength(3);
    const names = tools.map((t) => t.name);
    expect(names).toContain('get_calendar_events');
    expect(names).toContain('check_availability');
    expect(names).toContain('create_calendar_event');
    // all distinct
    expect(new Set(names).size).toBe(3);
  });

  it('all tools are ops tier with calendar:self scope', () => {
    const mockClient = buildMockClient();
    const tools = buildCalendarTools(mockClient);
    for (const tool of tools) {
      expect(tool.tier).toBe('ops');
      expect(tool.requiredScope).toBe('calendar:self');
    }
  });
});