import { describe, it, expect, mock, beforeEach, afterEach, spyOn } from 'bun:test';
import { logger } from '../../src/utils/logger.js';

import { Server } from '../../src/services/server/Server.js';
import type { RouteHandler, ServerOptions } from '../../src/services/server/Server.js';

let loggerSpies: ReturnType<typeof spyOn>[] = [];

describe('Server', () => {
  let server: Server;
  let mockOptions: ServerOptions;

  beforeEach(() => {
    loggerSpies = [
      spyOn(logger, 'info').mockImplementation(() => {}),
      spyOn(logger, 'debug').mockImplementation(() => {}),
      spyOn(logger, 'warn').mockImplementation(() => {}),
      spyOn(logger, 'error').mockImplementation(() => {}),
    ];

    mockOptions = {
      getInitializationComplete: () => true,
      getMcpReady: () => true,
      onShutdown: mock(() => Promise.resolve()),
      onRestart: mock(() => Promise.resolve()),
      workerPath: '/test/worker-service.cjs',
      getAiStatus: () => ({
        provider: 'claude',
        authMethod: 'cli',
        lastInteraction: null,
      }),
    };
  });

  afterEach(async () => {
    loggerSpies.forEach(spy => spy.mockRestore());
    if (server && server.getHttpServer()) {
      try {
        await server.close();
      } catch {
        // Ignore errors on cleanup
      }
    }
    mock.restore();
  });

  describe('constructor', () => {
    it('should create Express app', () => {
      server = new Server(mockOptions);

      expect(server.app).toBeDefined();
      expect(typeof server.app.get).toBe('function');
      expect(typeof server.app.post).toBe('function');
      expect(typeof server.app.use).toBe('function');
    });

    it('should expose app as readonly property', () => {
      server = new Server(mockOptions);

      expect(server.app).toBeDefined();

      expect(typeof server.app.listen).toBe('function');
    });

    it('should register pre-body-parser routes before normal middleware', async () => {
      server = new Server({
        ...mockOptions,
        preBodyParserRoutes: [{
          setupRoutes(app) {
            app.post('/api/auth/*splat', (req, res) => {
              res.json({
                bodyParsed: req.body !== undefined,
              });
            });
          },
        }],
      });

      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const response = await fetch(`http://127.0.0.1:${testPort}/api/auth/session`, {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
          Origin: 'http://localhost:37777',
        },
        body: JSON.stringify({ ok: true }),
      });

      expect(response.status).toBe(200);
      expect(response.headers.get('access-control-allow-origin')).toBe('http://localhost:37777');

      const body = await response.json();
      expect(body.bodyParsed).toBe(false);
    });
  });

  describe('listen', () => {
    it('should start server on specified port', async () => {
      server = new Server(mockOptions);

      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const httpServer = server.getHttpServer();
      expect(httpServer).not.toBeNull();
      expect(httpServer!.listening).toBe(true);
    });

    it('should reject if port is already in use', async () => {
      server = new Server(mockOptions);
      const server2 = new Server(mockOptions);

      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      await expect(server2.listen(testPort, '127.0.0.1')).rejects.toThrow();

      const httpServer = server2.getHttpServer();
      if (httpServer) {
        expect(httpServer.listening).toBe(false);
      }
    });
  });

  describe('close', () => {
    it('should stop server from listening after close', async () => {
      server = new Server(mockOptions);
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const httpServerBefore = server.getHttpServer();
      expect(httpServerBefore).not.toBeNull();
      expect(httpServerBefore!.listening).toBe(true);

      try {
        await server.close();
      } catch (e: any) {
        if (e.code !== 'ERR_SERVER_NOT_RUNNING') {
          throw e;
        }
      }

      const httpServerAfter = server.getHttpServer();
      if (httpServerAfter) {
        expect(httpServerAfter.listening).toBe(false);
      }
    });

    it('should handle close when server not started', async () => {
      server = new Server(mockOptions);

      await expect(server.close()).resolves.toBeUndefined();
    });

    it('should allow starting a new server on same port after close', async () => {
      server = new Server(mockOptions);
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      try {
        await server.close();
      } catch (e: any) {
        if (e.code !== 'ERR_SERVER_NOT_RUNNING') {
          throw e;
        }
      }

      await new Promise(resolve => setTimeout(resolve, 100));

      const server2 = new Server(mockOptions);
      await server2.listen(testPort, '127.0.0.1');

      expect(server2.getHttpServer()!.listening).toBe(true);

      try {
        await server2.close();
      } catch {
        // Ignore cleanup errors
      }
    });
  });

  describe('getHttpServer', () => {
    it('should return null before listen', () => {
      server = new Server(mockOptions);

      expect(server.getHttpServer()).toBeNull();
    });

    it('should return http.Server after listen', async () => {
      server = new Server(mockOptions);
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const httpServer = server.getHttpServer();
      expect(httpServer).not.toBeNull();
      expect(httpServer!.listening).toBe(true);
    });
  });

  describe('registerRoutes', () => {
    it('should call setupRoutes on route handler', () => {
      server = new Server(mockOptions);

      const setupRoutesMock = mock(() => {});
      const mockRouteHandler: RouteHandler = {
        setupRoutes: setupRoutesMock,
      };

      server.registerRoutes(mockRouteHandler);

      expect(setupRoutesMock).toHaveBeenCalledTimes(1);
      expect(setupRoutesMock).toHaveBeenCalledWith(server.app);
    });

    it('should register multiple route handlers', () => {
      server = new Server(mockOptions);

      const handler1Mock = mock(() => {});
      const handler2Mock = mock(() => {});

      const handler1: RouteHandler = { setupRoutes: handler1Mock };
      const handler2: RouteHandler = { setupRoutes: handler2Mock };

      server.registerRoutes(handler1);
      server.registerRoutes(handler2);

      expect(handler1Mock).toHaveBeenCalledTimes(1);
      expect(handler2Mock).toHaveBeenCalledTimes(1);
    });
  });

  describe('finalizeRoutes', () => {
    it('should not throw when called', () => {
      server = new Server(mockOptions);

      expect(() => server.finalizeRoutes()).not.toThrow();
    });
  });

  describe('health endpoint', () => {
    it('should return 200 with status ok', async () => {
      server = new Server(mockOptions);
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const response = await fetch(`http://127.0.0.1:${testPort}/api/health`);

      expect(response.status).toBe(200);

      const body = await response.json();
      expect(body.status).toBe('ok');
    });

    it('should include initialization status', async () => {
      server = new Server(mockOptions);
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const response = await fetch(`http://127.0.0.1:${testPort}/api/health`);
      const body = await response.json();

      expect(body.initialized).toBe(true);
      expect(body.mcpReady).toBe(true);
    });

    it('should reflect initialization state changes', async () => {
      let isInitialized = false;
      const dynamicOptions: ServerOptions = {
        getInitializationComplete: () => isInitialized,
        getMcpReady: () => true,
        onShutdown: mock(() => Promise.resolve()),
        onRestart: mock(() => Promise.resolve()),
        workerPath: '/test/worker-service.cjs',
        getAiStatus: () => ({ provider: 'claude', authMethod: 'cli', lastInteraction: null }),
      };

      server = new Server(dynamicOptions);
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      let response = await fetch(`http://127.0.0.1:${testPort}/api/health`);
      let body = await response.json();
      expect(body.initialized).toBe(false);

      isInitialized = true;

      response = await fetch(`http://127.0.0.1:${testPort}/api/health`);
      body = await response.json();
      expect(body.initialized).toBe(true);
    });

    it('should include platform and pid', async () => {
      server = new Server(mockOptions);
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const response = await fetch(`http://127.0.0.1:${testPort}/api/health`);
      const body = await response.json();

      expect(body.platform).toBeDefined();
      expect(body.pid).toBeDefined();
      expect(typeof body.pid).toBe('number');
    });

    it('should return degraded health when BullMQ Redis health is errored', async () => {
      server = new Server({
        ...mockOptions,
        getQueueHealth: () => ({
          engine: 'bullmq',
          redis: {
            status: 'error',
            mode: 'external',
            host: '127.0.0.1',
            port: 6379,
            prefix: 'test_prefix',
            error: 'connection refused',
          },
        }),
      });
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const response = await fetch(`http://127.0.0.1:${testPort}/api/health`);
      const body = await response.json();

      expect(response.status).toBe(503);
      expect(body.status).toBe('degraded');
      expect(body.queue.redis.status).toBe('error');
    });
  });

  describe('readiness endpoint', () => {
    it('should return 200 when initialized', async () => {
      server = new Server(mockOptions);
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const response = await fetch(`http://127.0.0.1:${testPort}/api/readiness`);

      expect(response.status).toBe(200);

      const body = await response.json();
      expect(body.status).toBe('ready');
    });

    it('should return 503 when not initialized', async () => {
      const uninitializedOptions: ServerOptions = {
        getInitializationComplete: () => false,
        getMcpReady: () => false,
        onShutdown: mock(() => Promise.resolve()),
        onRestart: mock(() => Promise.resolve()),
        workerPath: '/test/worker-service.cjs',
        getAiStatus: () => ({ provider: 'claude', authMethod: 'cli', lastInteraction: null }),
      };

      server = new Server(uninitializedOptions);
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const response = await fetch(`http://127.0.0.1:${testPort}/api/readiness`);

      expect(response.status).toBe(503);

      const body = await response.json();
      expect(body.status).toBe('initializing');
      expect(body.message).toBeDefined();
    });
  });

  describe('version endpoint', () => {
    it('should return 200 with version', async () => {
      server = new Server(mockOptions);
      const testPort = 40000 + Math.floor(Math.random() * 10000);

      await server.listen(testPort, '127.0.0.1');

      const response = await fetch(`http://127.0.0.1:${testPort}/api/version`);

      expect(response.status).toBe(200);

      const body = await response.json();
      expect(body.version).toBeDefined();
      expect(typeof body.version).toBe('string');
    });
  });

  describe('404 handling', () => {
    it('should return 404 for unknown routes after finalizeRoutes', async () => {
      server = new Server(mockOptions);
      server.finalizeRoutes();

      const testPort = 40000 + Math.floor(Math.random() * 10000);
      await server.listen(testPort, '127.0.0.1');

      const response = await fetch(`http://127.0.0.1:${testPort}/api/nonexistent`);

      expect(response.status).toBe(404);

      const body = await response.json();
      expect(body.error).toBe('NotFound');
    });
  });
});
