import { describe, it, expect, beforeAll, afterAll, vi } from 'vitest';
import { resolve } from 'path';
import { createServer } from 'net';
import type { GatewayServerConfig } from '../gateway/server.js';
import { GatewayServer } from '../gateway/server.js';
import { CompanionRuntimeClient, GatewayRpcError } from './runtimeClient.js';

async function canListenOnLocalhost(): Promise<boolean> {
  return new Promise((resolvePromise) => {
    const s = createServer();
    s.once('error', () => resolvePromise(false));
    s.listen(0, '127.0.0.1', () => {
      s.close(() => resolvePromise(true));
    });
  });
}

const mockSession = {
  id: 'test',
  addMessage: vi.fn(),
  getHistory: vi.fn(() => []),
  clear: vi.fn(),
  setHistory: vi.fn(),
  replaceHistory: vi.fn(),
};

const mockSessionManager = {
  getSession: vi.fn(() => mockSession),
  listSessions: vi.fn(() => ['ws:test']),
  transferSession: vi.fn(),
  closeSession: vi.fn(),
};

const mockModelClient = {
  chat: vi.fn(async () => ({
    content: 'Hello from Flynn!',
    stopReason: 'end_turn',
    usage: { inputTokens: 10, outputTokens: 5 },
  })),
};

const mockToolRegistry = {
  register: vi.fn(),
  get: vi.fn(),
  list: vi.fn(() => []),
  filteredList: vi.fn(() => []),
  toAnthropicFormat: vi.fn(() => []),
  toOpenAIFormat: vi.fn(() => []),
  filteredToAnthropicFormat: vi.fn(() => []),
  filteredToOpenAIFormat: vi.fn(() => []),
};

const mockToolExecutor = {
  execute: vi.fn(async () => ({ success: true, output: 'ok' })),
};

const TEST_PORT = 18911;
const TEST_TOKEN = 'runtime-client-token';

let LISTEN_ALLOWED = true;
let server: GatewayServer;

beforeAll(async () => {
  LISTEN_ALLOWED = await canListenOnLocalhost();
  if (!LISTEN_ALLOWED) {
    return;
  }

  server = new GatewayServer({
    port: TEST_PORT,
    sessionManager: mockSessionManager as unknown as GatewayServerConfig['sessionManager'],
    modelClient: mockModelClient,
    systemPrompt: 'Test prompt',
    toolRegistry: mockToolRegistry as unknown as GatewayServerConfig['toolRegistry'],
    toolExecutor: mockToolExecutor as unknown as GatewayServerConfig['toolExecutor'],
    version: '0.1.0-test',
    uiDir: resolve(import.meta.dirname, '../gateway/ui'),
    auth: { token: TEST_TOKEN },
    nodes: {
      enabled: true,
      allowedRoles: ['companion'],
      featureGates: { 'ui.canvas': true },
      locationEnabled: true,
      pushEnabled: true,
    },
  });

  await server.start();
});

afterAll(async () => {
  if (!LISTEN_ALLOWED) {
    return;
  }
  await server.stop();
});

describe('CompanionRuntimeClient', () => {
  it('validates requestTimeoutMs option', () => {
    expect(() => {
      new CompanionRuntimeClient({
        url: 'ws://127.0.0.1:1',
        requestTimeoutMs: 0,
      });
    }).toThrow('requestTimeoutMs must be a positive number');
  });

  it('dispatches gateway events to subscribed handlers and supports unsubscribe', () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });
    const handler = vi.fn();
    const unsubscribe = client.subscribeEvents(handler);

    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 42,
        event: 'agent.stream',
        data: { token: 'hello' },
      }),
    );

    expect(handler).toHaveBeenCalledWith('agent.stream', { token: 'hello' });

    unsubscribe();

    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 43,
        event: 'agent.stream',
        data: { token: 'world' },
      }),
    );

    expect(handler).toHaveBeenCalledTimes(1);
  });

  it('isolates subscriber callback failures', () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });
    const badHandler = vi.fn(() => {
      throw new Error('subscriber failed');
    });
    const goodHandler = vi.fn();
    client.subscribeEvents(badHandler);
    client.subscribeEvents(goodHandler);

    expect(() => {
      (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
        JSON.stringify({
          id: 44,
          event: 'agent.stream',
          data: { token: 'safe' },
        }),
      );
    }).not.toThrow();

    expect(badHandler).toHaveBeenCalledOnce();
    expect(goodHandler).toHaveBeenCalledWith('agent.stream', { token: 'safe' });
  });

  it('supports filtered subscribeEvent helper', () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });
    const streamHandler = vi.fn();
    const unsubscribe = client.subscribeEvent<{ token: string }>('agent.stream', streamHandler);

    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 45,
        event: 'agent.stream',
        data: { token: 'first' },
      }),
    );
    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 46,
        event: 'agent.typing',
        data: { active: true },
      }),
    );

    expect(streamHandler).toHaveBeenCalledTimes(1);
    expect(streamHandler).toHaveBeenCalledWith({ token: 'first' });

    unsubscribe();
    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 47,
        event: 'agent.stream',
        data: { token: 'second' },
      }),
    );
    expect(streamHandler).toHaveBeenCalledTimes(1);
  });

  it('supports subscribeAgentStream and subscribeAgentTyping helpers', () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });
    const streamHandler = vi.fn();
    const typingHandler = vi.fn();
    client.subscribeAgentStream(streamHandler);
    client.subscribeAgentTyping(typingHandler);

    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 52,
        event: 'agent.stream',
        data: { token: 'x' },
      }),
    );
    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 53,
        event: 'agent.typing',
        data: { active: true },
      }),
    );

    expect(streamHandler).toHaveBeenCalledWith({ token: 'x' });
    expect(typingHandler).toHaveBeenCalledWith({ active: true });
  });

  it('supports subscribeContextWarning helper', () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });
    const warningHandler = vi.fn();
    client.subscribeContextWarning(warningHandler);

    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 56,
        event: 'context_warning',
        data: { thresholdPct: 80, estimatedPct: 92 },
      }),
    );

    expect(warningHandler).toHaveBeenCalledWith({ thresholdPct: 80, estimatedPct: 92 });
  });

  it('clears all event subscriptions', () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });
    const handlerA = vi.fn();
    const handlerB = vi.fn();
    client.subscribeEvents(handlerA);
    client.subscribeEvent('agent.stream', handlerB);
    client.clearEventSubscriptions();

    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 50,
        event: 'agent.stream',
        data: { token: 'cleared' },
      }),
    );

    expect(handlerA).not.toHaveBeenCalled();
    expect(handlerB).not.toHaveBeenCalled();
  });

  it('dispose clears subscriptions and is safe to call repeatedly', () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });
    const handler = vi.fn();
    client.subscribeEvents(handler);

    client.dispose();
    client.dispose();

    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 51,
        event: 'agent.stream',
        data: { token: 'after-dispose' },
      }),
    );
    expect(handler).not.toHaveBeenCalled();
  });

  it('waitForEvent resolves using optional predicate filter', async () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });

    const awaited = client.waitForEvent<{ seq: number }>('agent.stream', {
      timeoutMs: 2000,
      predicate: (data) => data.seq === 2,
    });

    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 48,
        event: 'agent.stream',
        data: { seq: 1 },
      }),
    );
    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 49,
        event: 'agent.stream',
        data: { seq: 2 },
      }),
    );

    await expect(awaited).resolves.toEqual({ seq: 2 });
  });

  it('waitForEvent rejects on timeout', async () => {
    vi.useFakeTimers();
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });

    const awaited = expect(
      client.waitForEvent('agent.stream', { timeoutMs: 100 }),
    ).rejects.toThrow('Timed out waiting for event agent.stream');
    await vi.advanceTimersByTimeAsync(100);
    await awaited;
    vi.useRealTimers();
  });

  it('waitForEvent supports AbortSignal cancellation', async () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });
    const controller = new AbortController();

    const awaited = expect(
      client.waitForEvent('agent.stream', { signal: controller.signal, timeoutMs: 10_000 }),
    ).rejects.toThrow('Aborted while waiting for event agent.stream');
    controller.abort();
    await awaited;
  });

  it('waitForAgentStream resolves on agent.stream events', async () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });

    const awaited = client.waitForAgentStream<{ token: string }>({ timeoutMs: 2000 });
    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 54,
        event: 'agent.stream',
        data: { token: 'typed-stream' },
      }),
    );

    await expect(awaited).resolves.toEqual({ token: 'typed-stream' });
  });

  it('waitForAgentTyping resolves on agent.typing events', async () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });

    const awaited = client.waitForAgentTyping<{ active: boolean }>({ timeoutMs: 2000 });
    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 55,
        event: 'agent.typing',
        data: { active: true },
      }),
    );

    await expect(awaited).resolves.toEqual({ active: true });
  });

  it('waitForContextWarning resolves on context_warning events', async () => {
    const client = new CompanionRuntimeClient({
      url: 'ws://127.0.0.1:1',
    });

    const awaited = client.waitForContextWarning<{ thresholdPct: number; estimatedPct: number }>({
      timeoutMs: 2000,
    });
    (client as unknown as { handleMessage: (raw: string) => void }).handleMessage(
      JSON.stringify({
        id: 57,
        event: 'context_warning',
        data: { thresholdPct: 75, estimatedPct: 88 },
      }),
    );

    await expect(awaited).resolves.toEqual({ thresholdPct: 75, estimatedPct: 88 });
  });

  it('connects and performs node registration + capability discovery', async () => {
    if (!LISTEN_ALLOWED) {
      return;
    }

    const client = new CompanionRuntimeClient({
      url: `ws://127.0.0.1:${TEST_PORT}`,
      token: TEST_TOKEN,
    });

    await client.connect();
    expect(client.connected).toBe(true);

    try {
      const register = await client.registerNode({
        nodeId: 'macos-companion',
        role: 'companion',
        capabilities: ['ui.canvas', 'node.location.read'],
      });

      expect(register.registered).toBe(true);
      expect(register.node.id).toBe('macos-companion');
      expect(register.protocol.serverVersion).toBe(1);
      expect(register.capabilities.enabled).toContain('ui.canvas');

      const nodeCaps = await client.getNodeCapabilities();
      expect(nodeCaps.node.id).toBe('macos-companion');
      expect(nodeCaps.capabilities.enabled).toContain('ui.canvas');

      const systemCaps = await client.getSystemCapabilities();
      expect(systemCaps.nodes.enabled).toBe(true);
      expect(systemCaps.nodes.registered).toBe(true);
      expect(systemCaps.nodes.nodeId).toBe('macos-companion');
    } finally {
      client.disconnect();
    }
  });

  it('bootstraps node registration and capabilities in one call', async () => {
    if (!LISTEN_ALLOWED) {
      return;
    }

    const client = new CompanionRuntimeClient({
      url: `ws://127.0.0.1:${TEST_PORT}`,
      token: TEST_TOKEN,
    });
    await client.connect();

    try {
      const boot = await client.bootstrapNode(
        {
          nodeId: 'bootstrap-runtime-node',
          role: 'companion',
          capabilities: ['ui.canvas'],
        },
        { includeSystemCapabilities: true },
      );

      expect(boot.register.registered).toBe(true);
      expect(boot.capabilities.node.id).toBe('bootstrap-runtime-node');
      expect(boot.systemCapabilities?.nodes.enabled).toBe(true);
      expect(boot.systemCapabilities?.nodes.registered).toBe(true);
    } finally {
      client.disconnect();
    }
  });

  it('updates status/location/push and exposes them through system.nodes', async () => {
    if (!LISTEN_ALLOWED) {
      return;
    }

    const client = new CompanionRuntimeClient({
      url: `ws://127.0.0.1:${TEST_PORT}`,
      token: TEST_TOKEN,
    });

    await client.connect();

    try {
      await client.registerNode({
        nodeId: 'ios-companion',
        role: 'companion',
        capabilities: ['node.location.write', 'node.push.register'],
      });

      const status = await client.setNodeStatus({
        platform: 'ios',
        appVersion: '1.2.3',
        batteryPct: 77,
        powerSource: 'battery',
      });
      expect(status.updated).toBe(true);
      expect(status.status.platform).toBe('ios');

      const location = await client.setNodeLocation({
        latitude: 37.78,
        longitude: -122.41,
        source: 'gps',
      });
      expect(location.updated).toBe(true);
      expect(location.location.source).toBe('gps');

      const locationGet = await client.getNodeLocation();
      expect(locationGet.location?.latitude).toBe(37.78);

      const push = await client.setNodePushToken({
        provider: 'apns',
        token: 'abcdef1234567890abcdef1234567890abcdef1234567890abcdef1234567890',
        topic: 'dev.flynn.companion',
        environment: 'production',
      });
      expect(push.updated).toBe(true);
      expect(push.push.provider).toBe('apns');
      expect(push.push.tokenPreview.startsWith('***')).toBe(true);

      const nodes = await client.listSystemNodes({ role: 'companion', platform: 'ios' });
      expect(nodes.summary.total).toBeGreaterThanOrEqual(1);
      const current = nodes.nodes.find((entry) => entry.nodeId === 'ios-companion');
      expect(current).toBeTruthy();
      expect(current?.status?.platform).toBe('ios');
      expect(current?.push?.provider).toBe('apns');
    } finally {
      client.disconnect();
    }
  });

  it('surfaces gateway errors as GatewayRpcError', async () => {
    if (!LISTEN_ALLOWED) {
      return;
    }

    const client = new CompanionRuntimeClient({
      url: `ws://127.0.0.1:${TEST_PORT}`,
      token: TEST_TOKEN,
    });

    await client.connect();

    try {
      await expect(client.registerNode({
        nodeId: 'observer-node',
        role: 'observer',
        capabilities: ['node.location.read'],
      })).rejects.toBeInstanceOf(GatewayRpcError);

      await expect(client.registerNode({
        nodeId: 'observer-node',
        role: 'observer',
        capabilities: ['node.location.read'],
      })).rejects.toMatchObject({
        code: -5,
      });
    } finally {
      client.disconnect();
    }
  });

  it('supports canvas artifact lifecycle via typed helper methods', async () => {
    if (!LISTEN_ALLOWED) {
      return;
    }

    const client = new CompanionRuntimeClient({
      url: `ws://127.0.0.1:${TEST_PORT}`,
      token: TEST_TOKEN,
    });

    await client.connect();

    try {
      const sessionId = 'ws:companion-canvas';
      const put = await client.putCanvasArtifact({
        sessionId,
        artifactId: 'artifact-1',
        type: 'markdown',
        title: 'Companion note',
        content: { body: '# Hello' },
        metadata: { source: 'runtime-client-test' },
      });
      expect(put.upserted).toBe(true);
      expect(put.artifact.id).toBe('artifact-1');
      expect(put.artifact.type).toBe('markdown');

      const list = await client.listCanvasArtifacts(sessionId);
      expect(list.artifacts.length).toBeGreaterThanOrEqual(1);
      expect(list.artifacts.some((artifact) => artifact.id === 'artifact-1')).toBe(true);

      const get = await client.getCanvasArtifact({ sessionId, artifactId: 'artifact-1' });
      expect(get.artifact.id).toBe('artifact-1');
      expect(get.artifact.title).toBe('Companion note');

      const del = await client.deleteCanvasArtifact({ sessionId, artifactId: 'artifact-1' });
      expect(del.deleted).toBe(true);

      const clear = await client.clearCanvasArtifacts(sessionId);
      expect(clear.cleared).toBe(0);
    } finally {
      client.disconnect();
    }
  });

  it('supports autoConnect mode for one-shot RPC usage', async () => {
    if (!LISTEN_ALLOWED) {
      return;
    }

    const client = new CompanionRuntimeClient({
      url: `ws://127.0.0.1:${TEST_PORT}`,
      token: TEST_TOKEN,
      autoConnect: true,
    });

    expect(client.connected).toBe(false);

    try {
      const register = await client.registerNode({
        nodeId: 'auto-connect-node',
        role: 'companion',
        capabilities: ['ui.canvas'],
      });

      expect(register.registered).toBe(true);
      expect(client.connected).toBe(true);
    } finally {
      client.disconnect();
    }
  });
});