import { beforeEach, describe, expect, it, vi } from 'vitest';

const hostApiFetchMock = vi.fn();
const subscribeHostEventMock = vi.fn();
const chatStateMock = vi.hoisted(() => ({
  state: {
    currentSessionKey: 'session-1',
    sessions: [] as Array<{ key: string }>,
    sending: true,
    activeRunId: 'run-1' as string | null,
    pendingFinal: true,
    lastUserMessageAt: 123,
    error: null as string | null,
    loadHistory: vi.fn(),
    loadSessions: vi.fn(),
    handleChatEvent: vi.fn(),
  },
}));

vi.mock('@/lib/host-api', () => ({
  hostApiFetch: (...args: unknown[]) => hostApiFetchMock(...args),
}));

vi.mock('@/lib/host-events', () => ({
  subscribeHostEvent: (...args: unknown[]) => subscribeHostEventMock(...args),
}));

vi.mock('@/stores/chat', () => ({
  useChatStore: {
    getState: () => chatStateMock.state,
    setState: (patch: Record<string, unknown>) => {
      Object.assign(chatStateMock.state, patch);
    },
  },
}));

describe('gateway store event wiring', () => {
  beforeEach(() => {
    vi.resetModules();
    vi.clearAllMocks();
    Object.assign(chatStateMock.state, {
      currentSessionKey: 'session-1',
      sessions: [],
      sending: true,
      activeRunId: 'run-1',
      pendingFinal: true,
      lastUserMessageAt: 123,
      error: null,
    });
  });

  it('subscribes to host events through subscribeHostEvent on init', async () => {
    hostApiFetchMock.mockResolvedValueOnce({ state: 'running', port: 18789 });

    const handlers = new Map<string, (payload: unknown) => void>();
    subscribeHostEventMock.mockImplementation((eventName: string, handler: (payload: unknown) => void) => {
      handlers.set(eventName, handler);
      return () => {};
    });

    const { useGatewayStore } = await import('@/stores/gateway');
    await useGatewayStore.getState().init();

    expect(subscribeHostEventMock).toHaveBeenCalledWith('gateway:status', expect.any(Function));
    expect(subscribeHostEventMock).toHaveBeenCalledWith('gateway:error', expect.any(Function));
    expect(subscribeHostEventMock).toHaveBeenCalledWith('gateway:notification', expect.any(Function));
    expect(subscribeHostEventMock).toHaveBeenCalledWith('gateway:chat-message', expect.any(Function));
    expect(subscribeHostEventMock).toHaveBeenCalledWith('gateway:channel-status', expect.any(Function));

    handlers.get('gateway:status')?.({ state: 'stopped', port: 18789 });
    expect(useGatewayStore.getState().status.state).toBe('stopped');
  });

  it('propagates gatewayReady field from status events', async () => {
    hostApiFetchMock.mockResolvedValueOnce({ state: 'running', port: 18789, gatewayReady: false });

    const handlers = new Map<string, (payload: unknown) => void>();
    subscribeHostEventMock.mockImplementation((eventName: string, handler: (payload: unknown) => void) => {
      handlers.set(eventName, handler);
      return () => {};
    });

    const { useGatewayStore } = await import('@/stores/gateway');
    await useGatewayStore.getState().init();

    // Initially gatewayReady=false from the status fetch
    expect(useGatewayStore.getState().status.gatewayReady).toBe(false);

    // Simulate gateway.ready event setting gatewayReady=true
    handlers.get('gateway:status')?.({ state: 'running', port: 18789, gatewayReady: true });
    expect(useGatewayStore.getState().status.gatewayReady).toBe(true);
  });

  it('treats undefined gatewayReady as ready for backwards compatibility', async () => {
    hostApiFetchMock.mockResolvedValueOnce({ state: 'running', port: 18789 });

    const handlers = new Map<string, (payload: unknown) => void>();
    subscribeHostEventMock.mockImplementation((eventName: string, handler: (payload: unknown) => void) => {
      handlers.set(eventName, handler);
      return () => {};
    });

    const { useGatewayStore } = await import('@/stores/gateway');
    await useGatewayStore.getState().init();

    const status = useGatewayStore.getState().status;
    // gatewayReady is undefined (old gateway version) — should be treated as ready
    expect(status.gatewayReady).toBeUndefined();
    expect(status.state === 'running' && status.gatewayReady !== false).toBe(true);
  });

  it('does not clear sending state on intermediate agent phase=end notifications', async () => {
    hostApiFetchMock.mockResolvedValueOnce({ state: 'running', port: 18789 });

    const handlers = new Map<string, (payload: unknown) => void>();
    subscribeHostEventMock.mockImplementation((eventName: string, handler: (payload: unknown) => void) => {
      handlers.set(eventName, handler);
      return () => {};
    });

    const { useGatewayStore } = await import('@/stores/gateway');
    await useGatewayStore.getState().init();

    handlers.get('gateway:notification')?.({
      method: 'agent',
      params: {
        phase: 'end',
        runId: 'run-1',
        sessionKey: 'session-1',
      },
    });

    await vi.waitFor(() => {
      expect(chatStateMock.state.loadHistory).toHaveBeenCalled();
    });
    expect(chatStateMock.state.sending).toBe(true);
    expect(chatStateMock.state.activeRunId).toBe('run-1');
    expect(chatStateMock.state.pendingFinal).toBe(true);
  });

  it('clears sending state on terminal agent completion notifications', async () => {
    hostApiFetchMock.mockResolvedValueOnce({ state: 'running', port: 18789 });

    const handlers = new Map<string, (payload: unknown) => void>();
    subscribeHostEventMock.mockImplementation((eventName: string, handler: (payload: unknown) => void) => {
      handlers.set(eventName, handler);
      return () => {};
    });

    const { useGatewayStore } = await import('@/stores/gateway');
    await useGatewayStore.getState().init();

    handlers.get('gateway:notification')?.({
      method: 'agent',
      params: {
        phase: 'completed',
        runId: 'run-1',
        sessionKey: 'session-1',
      },
    });

    await vi.waitFor(() => {
      expect(chatStateMock.state.sending).toBe(false);
    });
    expect(chatStateMock.state.activeRunId).toBeNull();
    expect(chatStateMock.state.pendingFinal).toBe(false);
  });
});