/**
 * OpenFang Mock Server for Testing
 *
 * Simulates OpenFang Kernel API endpoints and WebSocket events.
 * Provides a complete test double for the ZCLAW desktop client.
 *
 * Usage:
 *   const server = createOpenFangMockServer({ port: 4200 });
 *   await server.start();
 *   // ... run tests ...
 *   await server.stop();
 */

import { createServer, IncomingMessage, Server, ServerResponse } from 'http';
import { WebSocketServer, WebSocket, RawData } from 'ws';

// === Types ===

export interface MockServerConfig {
  port?: number;
  host?: string;
  version?: string;
  connectionDelay?: number;
  challengeDelay?: number;
}

export interface MockServerInstance {
  start: () => Promise<void>;
  stop: () => Promise<void>;
  getPort: () => number;
  getWsUrl: () => string;
  getHttpUrl: () => string;
  reset: () => void;
  setHands: (hands: MockHand[]) => void;
  setWorkflows: (workflows: MockWorkflow[]) => void;
  setTriggers: (triggers: MockTrigger[]) => void;
  setAgents: (agents: MockAgent[]) => void;
  setSecurityLayers: (layers: MockSecurityLayer[]) => void;
  addAuditLog: (entry: Omit<MockAuditLogEntry, 'id' | 'timestamp'>) => void;
  simulateStreamEvent: (event: string, payload: unknown) => void;
  getConnectedClients: () => number;
}

export interface MockHand {
  name: string;
  description: string;
  status: 'idle' | 'running' | 'needs_approval' | 'completed' | 'error';
  config?: Record<string, unknown>;
}

export interface MockWorkflow {
  id: string;
  name: string;
  steps: number;
  description?: string;
}

export interface MockTrigger {
  id: string;
  type: 'webhook' | 'schedule' | 'event';
  enabled: boolean;
  config?: Record<string, unknown>;
}

export interface MockAgent {
  id: string;
  name: string;
  role?: string;
  nickname?: string;
  scenarios?: string[];
  model?: string;
  workspaceDir?: string;
  workspaceResolvedPath?: string;
  restrictFiles?: boolean;
  privacyOptIn?: boolean;
  userName?: string;
  userRole?: string;
  createdAt: string;
  updatedAt?: string;
  bootstrapReady?: boolean;
}

export interface MockSecurityLayer {
  name: string;
  enabled: boolean;
  description?: string;
}

export interface MockAuditLogEntry {
  id: string;
  timestamp: string;
  action: string;
  actor?: string;
  result?: 'success' | 'failure';
  details?: Record<string, unknown>;
}

// === Sample Data ===

const DEFAULT_HANDS: MockHand[] = [
  { name: 'clip', description: 'Video processing and vertical screen generation', status: 'idle' },
  { name: 'lead', description: 'Sales lead discovery and qualification', status: 'idle' },
  { name: 'collector', description: 'Data collection and aggregation', status: 'idle' },
  { name: 'predictor', description: 'Predictive analytics', status: 'idle' },
  { name: 'researcher', description: 'Deep research and analysis', status: 'idle' },
  { name: 'twitter', description: 'Twitter automation', status: 'idle' },
  { name: 'browser', description: 'Browser automation', status: 'idle' },
];

const DEFAULT_WORKFLOWS: MockWorkflow[] = [
  { id: 'wf-001', name: 'Daily Report', steps: 3, description: 'Generate daily summary report' },
  { id: 'wf-002', name: 'Data Pipeline', steps: 5, description: 'ETL data processing pipeline' },
  { id: 'wf-003', name: 'Research Task', steps: 4, description: 'Multi-step research workflow' },
];

const DEFAULT_TRIGGERS: MockTrigger[] = [
  { id: 'tr-001', type: 'schedule', enabled: true, config: { cron: '0 9 * * *' } },
  { id: 'tr-002', type: 'webhook', enabled: true, config: { path: '/hooks/data' } },
  { id: 'tr-003', type: 'event', enabled: false, config: { eventType: 'data.received' } },
];

const DEFAULT_AGENTS: MockAgent[] = [
  {
    id: 'agent-001',
    name: 'Default Agent',
    role: 'assistant',
    nickname: 'ZCLAW',
    scenarios: ['general', 'coding'],
    model: 'gpt-4',
    workspaceDir: '~/.openfang/workspaces/default',
    workspaceResolvedPath: '/home/user/.openfang/workspaces/default',
    restrictFiles: false,
    privacyOptIn: false,
    userName: 'User',
    userRole: 'developer',
    createdAt: new Date().toISOString(),
    bootstrapReady: true,
  },
];

const DEFAULT_SECURITY_LAYERS: MockSecurityLayer[] = [
  { name: 'input_validation', enabled: true, description: 'Input sanitization and validation' },
  { name: 'rate_limiting', enabled: true, description: 'Request rate limiting' },
  { name: 'authentication', enabled: true, description: 'Ed25519 + JWT authentication' },
  { name: 'authorization', enabled: true, description: 'RBAC capability gates' },
  { name: 'encryption_at_rest', enabled: true, description: 'Data encryption at rest' },
  { name: 'encryption_in_transit', enabled: true, description: 'TLS encryption' },
  { name: 'audit_logging', enabled: true, description: 'Merkle hash chain audit' },
  { name: 'session_management', enabled: true, description: 'Secure session handling' },
  { name: 'device_attestation', enabled: true, description: 'Device identity verification' },
  { name: 'content_security', enabled: true, description: 'Content Security Policy' },
  { name: 'csp_headers', enabled: true, description: 'HTTP security headers' },
  { name: 'cors_policy', enabled: true, description: 'Cross-origin resource policy' },
  { name: 'sandbox_isolation', enabled: true, description: 'Process sandboxing' },
  { name: 'secret_management', enabled: true, description: 'Secure secret storage' },
  { name: 'intrusion_detection', enabled: false, description: 'IDS monitoring' },
  { name: 'backup_recovery', enabled: true, description: 'Backup and disaster recovery' },
];

// === Server Implementation ===

export function createOpenFangMockServer(config: MockServerConfig = {}): MockServerInstance {
  const {
    port = 4200,
    host = '127.0.0.1',
    version = '2026.3.13',
    connectionDelay = 0,
    challengeDelay = 0,
  } = config;

  let httpServer: Server | null = null;
  let wsServer: WebSocketServer | null = null;
  let actualPort = port;

  // Mutable state
  let hands = [...DEFAULT_HANDS];
  let workflows = [...DEFAULT_WORKFLOWS];
  let triggers = [...DEFAULT_TRIGGERS];
  let agents = [...DEFAULT_AGENTS];
  let securityLayers = [...DEFAULT_SECURITY_LAYERS];
  let auditLogs: MockAuditLogEntry[] = [];
  let handRuns = new Map<string, { status: string; result?: unknown; startedAt: string }>();
  let workflowRuns = new Map<string, { status: string; step?: string; result?: unknown }>();
  const connectedClients = new Set<WebSocket>();

  // === REST API Handlers ===

  function handleHealth(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, { version, status: 'ok' });
  }

  function handleGetAgents(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, { clones: agents });
  }

  function handleCreateAgent(req: IncomingMessage, res: ServerResponse): void {
    parseBody(req, (body) => {
      const newAgent: MockAgent = {
        id: `agent-${Date.now()}`,
        name: body.name || 'New Agent',
        role: body.role,
        nickname: body.nickname,
        scenarios: body.scenarios,
        model: body.model,
        workspaceDir: body.workspaceDir,
        restrictFiles: body.restrictFiles,
        privacyOptIn: body.privacyOptIn,
        userName: body.userName,
        userRole: body.userRole,
        createdAt: new Date().toISOString(),
      };
      agents.push(newAgent);
      addAuditLogEntry({
        action: 'agent.created',
        actor: 'system',
        result: 'success',
        details: { agentId: newAgent.id, name: newAgent.name },
      });
      sendJson(res, { clone: newAgent }, 201);
    });
  }

  function handleUpdateAgent(req: IncomingMessage, res: ServerResponse, agentId: string): void {
    parseBody(req, (body) => {
      const index = agents.findIndex((a) => a.id === agentId);
      if (index === -1) {
        sendError(res, 'Agent not found', 404);
        return;
      }
      agents[index] = { ...agents[index], ...body, updatedAt: new Date().toISOString() };
      addAuditLogEntry({
        action: 'agent.updated',
        actor: 'system',
        result: 'success',
        details: { agentId, updates: body },
      });
      sendJson(res, { clone: agents[index] });
    });
  }

  function handleDeleteAgent(_req: IncomingMessage, res: ServerResponse, agentId: string): void {
    const index = agents.findIndex((a) => a.id === agentId);
    if (index === -1) {
      sendError(res, 'Agent not found', 404);
      return;
    }
    agents.splice(index, 1);
    addAuditLogEntry({
      action: 'agent.deleted',
      actor: 'system',
      result: 'success',
      details: { agentId },
    });
    sendJson(res, { ok: true });
  }

  function handleGetHands(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, { hands });
  }

  function handleGetHand(_req: IncomingMessage, res: ServerResponse, name: string): void {
    const hand = hands.find((h) => h.name === name);
    if (!hand) {
      sendError(res, 'Hand not found', 404);
      return;
    }
    sendJson(res, { name: hand.name, description: hand.description, config: hand.config || {} });
  }

  function handleTriggerHand(_req: IncomingMessage, res: ServerResponse, name: string): void {
    const hand = hands.find((h) => h.name === name);
    if (!hand) {
      sendError(res, 'Hand not found', 404);
      return;
    }

    const runId = `run-${name}-${Date.now()}`;
    const needsApproval = name === 'lead' || name === 'twitter'; // Some hands need approval

    const status = needsApproval ? 'needs_approval' : 'running';
    handRuns.set(runId, { status, startedAt: new Date().toISOString() });

    // Update hand status
    const handIndex = hands.findIndex((h) => h.name === name);
    hands[handIndex] = { ...hand, status: needsApproval ? 'needs_approval' : 'running' };

    addAuditLogEntry({
      action: 'hand.triggered',
      actor: 'system',
      result: 'success',
      details: { handName: name, runId, needsApproval },
    });

    sendJson(res, { runId, status });

    // Simulate async events for running hands
    if (!needsApproval) {
      setTimeout(() => {
        simulateStreamEvent('hand', {
          handName: name,
          runId,
          status: 'running',
          phase: 'start',
        });
      }, 100);
    }
  }

  function handleApproveHand(_req: IncomingMessage, res: ServerResponse, name: string, runId: string): void {
    parseBody(_req, (body) => {
      const run = handRuns.get(runId);
      if (!run) {
        sendError(res, 'Run not found', 404);
        return;
      }

      const approved = body.approved === true;
      run.status = approved ? 'running' : 'cancelled';
      handRuns.set(runId, run);

      addAuditLogEntry({
        action: approved ? 'hand.approved' : 'hand.rejected',
        actor: 'operator',
        result: 'success',
        details: { handName: name, runId, reason: body.reason },
      });

      sendJson(res, { status: run.status });

      if (approved) {
        simulateStreamEvent('hand', {
          handName: name,
          runId,
          status: 'running',
          phase: 'start',
        });
      }
    });
  }

  function handleCancelHand(_req: IncomingMessage, res: ServerResponse, name: string, runId: string): void {
    const run = handRuns.get(runId);
    if (!run) {
      sendError(res, 'Run not found', 404);
      return;
    }

    run.status = 'cancelled';
    handRuns.set(runId, run);

    addAuditLogEntry({
      action: 'hand.cancelled',
      actor: 'operator',
      result: 'success',
      details: { handName: name, runId },
    });

    sendJson(res, { status: 'cancelled' });
  }

  function handleGetHandRuns(_req: IncomingMessage, res: ServerResponse, name: string): void {
    const runs = Array.from(handRuns.entries())
      .filter(([runId]) => runId.startsWith(`run-${name}-`))
      .map(([runId, data]) => ({
        runId,
        status: data.status,
        startedAt: data.startedAt,
      }));
    sendJson(res, { runs });
  }

  function handleGetWorkflows(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, { workflows });
  }

  function handleGetWorkflow(_req: IncomingMessage, res: ServerResponse, id: string): void {
    const workflow = workflows.find((w) => w.id === id);
    if (!workflow) {
      sendError(res, 'Workflow not found', 404);
      return;
    }
    sendJson(res, {
      id: workflow.id,
      name: workflow.name,
      steps: Array.from({ length: workflow.steps }, (_, i) => ({
        id: `step-${i + 1}`,
        name: `Step ${i + 1}`,
      })),
    });
  }

  function handleExecuteWorkflow(_req: IncomingMessage, res: ServerResponse, id: string): void {
    const workflow = workflows.find((w) => w.id === id);
    if (!workflow) {
      sendError(res, 'Workflow not found', 404);
      return;
    }

    parseBody(_req, (body) => {
      const runId = `wf-run-${id}-${Date.now()}`;
      workflowRuns.set(runId, { status: 'running', step: 'step-1' });

      addAuditLogEntry({
        action: 'workflow.started',
        actor: 'system',
        result: 'success',
        details: { workflowId: id, runId, input: body },
      });

      sendJson(res, { runId, status: 'running' });

      // Simulate workflow progress
      setTimeout(() => {
        simulateStreamEvent('workflow', {
          workflowId: id,
          runId,
          status: 'running',
          step: 'step-1',
          workflowStatus: 'executing',
        });
      }, 100);
    });
  }

  function handleGetWorkflowRun(_req: IncomingMessage, res: ServerResponse, workflowId: string, runId: string): void {
    const run = workflowRuns.get(runId);
    if (!run) {
      sendError(res, 'Run not found', 404);
      return;
    }
    sendJson(res, { status: run.status, step: run.step, result: run.result });
  }

  function handleCancelWorkflow(_req: IncomingMessage, res: ServerResponse, workflowId: string, runId: string): void {
    const run = workflowRuns.get(runId);
    if (!run) {
      sendError(res, 'Run not found', 404);
      return;
    }

    run.status = 'cancelled';
    workflowRuns.set(runId, run);

    addAuditLogEntry({
      action: 'workflow.cancelled',
      actor: 'operator',
      result: 'success',
      details: { workflowId, runId },
    });

    sendJson(res, { status: 'cancelled' });
  }

  function handleGetTriggers(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, { triggers });
  }

  function handleGetAuditLogs(req: IncomingMessage, res: ServerResponse): void {
    const url = new URL(req.url || '/', `http://${host}`);
    const limit = parseInt(url.searchParams.get('limit') || '50', 10);
    const offset = parseInt(url.searchParams.get('offset') || '0', 10);

    const paginatedLogs = auditLogs.slice(offset, offset + limit);
    sendJson(res, { logs: paginatedLogs, total: auditLogs.length });
  }

  function handleGetSecurityStatus(_req: IncomingMessage, res: ServerResponse): void {
    const enabledCount = securityLayers.filter((l) => l.enabled).length;
    sendJson(res, {
      layers: securityLayers,
      enabledCount,
      totalCount: securityLayers.length,
      securityLevel: calculateSecurityLevel(enabledCount, securityLayers.length),
    });
  }

  function handleGetCapabilities(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, {
      capabilities: [
        'operator.read',
        'operator.write',
        'operator.admin',
        'operator.approvals',
        'operator.pairing',
      ],
    });
  }

  function handleChat(req: IncomingMessage, res: ServerResponse): void {
    parseBody(req, (body) => {
      const runId = `chat-${Date.now()}`;
      const sessionId = body.session_id || `session-${Date.now()}`;

      addAuditLogEntry({
        action: 'chat.message',
        actor: body.agent_id || 'default',
        result: 'success',
        details: { runId, sessionId, messageLength: body.message?.length || 0 },
      });

      sendJson(res, { runId, sessionId });

      // Simulate streaming events
      setTimeout(() => {
        simulateStreamEvent('agent', {
          stream: 'assistant',
          delta: 'Hello',
          runId,
        });
        setTimeout(() => {
          simulateStreamEvent('agent', {
            stream: 'assistant',
            delta: '! How can I help you today?',
            runId,
          });
          setTimeout(() => {
            simulateStreamEvent('agent', {
              stream: 'lifecycle',
              phase: 'end',
              runId,
            });
          }, 100);
        }, 100);
      }, 100);
    });
  }

  function handleGetModels(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, {
      models: [
        { id: 'gpt-4', name: 'GPT-4', provider: 'openai' },
        { id: 'gpt-3.5-turbo', name: 'GPT-3.5 Turbo', provider: 'openai' },
        { id: 'claude-3-sonnet', name: 'Claude 3 Sonnet', provider: 'anthropic' },
        { id: 'deepseek-chat', name: 'DeepSeek Chat', provider: 'deepseek' },
      ],
    });
  }

  function handleGetConfig(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, {
      server: { host: '127.0.0.1', port: actualPort },
      agent: { default_model: 'gpt-4' },
      llm: {
        providers: [
          { name: 'openai', api_key: '${OPENAI_API_KEY}' },
        ],
      },
    });
  }

  function handleGetQuickConfig(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, {
      quickConfig: {
        agentName: 'ZCLAW',
        agentRole: 'assistant',
        userName: 'User',
        userRole: 'developer',
        theme: 'dark',
        showToolCalls: true,
      },
    });
  }

  function handleGetWorkspace(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, {
      path: '~/.openfang/workspaces/default',
      resolvedPath: '/home/user/.openfang/workspaces/default',
      exists: true,
      fileCount: 42,
      totalSize: 1024 * 1024 * 5, // 5MB
    });
  }

  function handleGetSkills(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, {
      skills: [
        { id: 'skill-001', name: 'Code Review', path: '/skills/code-review', source: 'builtin' },
        { id: 'skill-002', name: 'Translation', path: '/skills/translation', source: 'builtin' },
        { id: 'skill-003', name: 'Research', path: '/skills/research', source: 'extra' },
      ],
      extraDirs: ['/extra/skills'],
    });
  }

  function handleGetChannels(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, {
      channels: [
        { id: 'feishu', type: 'feishu', label: 'Feishu', status: 'active', accounts: 1 },
      ],
    });
  }

  function handleGetStatsUsage(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, {
      totalSessions: 10,
      totalMessages: 150,
      totalTokens: 50000,
      byModel: {
        'gpt-4': { messages: 100, inputTokens: 30000, outputTokens: 15000 },
        'claude-3-sonnet': { messages: 50, inputTokens: 4000, outputTokens: 1000 },
      },
    });
  }

  function handleGetPluginsStatus(_req: IncomingMessage, res: ServerResponse): void {
    sendJson(res, {
      plugins: [
        { id: 'feishu', name: 'Feishu Integration', status: 'active' },
        { id: 'chinese-models', name: 'Chinese Models', status: 'active' },
      ],
    });
  }

  // === HTTP Request Handler ===

  function handleRequest(req: IncomingMessage, res: ServerResponse): void {
    // Add CORS headers
    res.setHeader('Access-Control-Allow-Origin', '*');
    res.setHeader('Access-Control-Allow-Methods', 'GET, POST, PUT, DELETE, OPTIONS');
    res.setHeader('Access-Control-Allow-Headers', 'Content-Type, Authorization');

    if (req.method === 'OPTIONS') {
      res.writeHead(204);
      res.end();
      return;
    }

    const url = new URL(req.url || '/', `http://${host}`);
    const path = url.pathname;

    // Route matching
    const routes: Array<{
      method: string | string[];
      pattern: RegExp;
      handler: (req: IncomingMessage, res: ServerResponse, ...matches: string[]) => void;
    }> = [
      { method: 'GET', pattern: /^\/api\/health$/, handler: handleHealth },
      { method: 'GET', pattern: /^\/api\/agents$/, handler: handleGetAgents },
      { method: 'POST', pattern: /^\/api\/agents$/, handler: handleCreateAgent },
      { method: 'PUT', pattern: /^\/api\/agents\/([^/]+)$/, handler: handleUpdateAgent },
      { method: 'DELETE', pattern: /^\/api\/agents\/([^/]+)$/, handler: handleDeleteAgent },
      { method: 'GET', pattern: /^\/api\/hands$/, handler: handleGetHands },
      { method: 'GET', pattern: /^\/api\/hands\/([^/]+)$/, handler: handleGetHand },
      { method: 'POST', pattern: /^\/api\/hands\/([^/]+)\/trigger$/, handler: handleTriggerHand },
      { method: 'POST', pattern: /^\/api\/hands\/([^/]+)\/runs\/([^/]+)\/approve$/, handler: handleApproveHand },
      { method: 'POST', pattern: /^\/api\/hands\/([^/]+)\/runs\/([^/]+)\/cancel$/, handler: handleCancelHand },
      { method: 'GET', pattern: /^\/api\/hands\/([^/]+)\/runs$/, handler: handleGetHandRuns },
      { method: 'GET', pattern: /^\/api\/workflows$/, handler: handleGetWorkflows },
      { method: 'GET', pattern: /^\/api\/workflows\/([^/]+)$/, handler: handleGetWorkflow },
      { method: 'POST', pattern: /^\/api\/workflows\/([^/]+)\/execute$/, handler: handleExecuteWorkflow },
      { method: 'GET', pattern: /^\/api\/workflows\/([^/]+)\/runs\/([^/]+)$/, handler: handleGetWorkflowRun },
      { method: 'POST', pattern: /^\/api\/workflows\/([^/]+)\/runs\/([^/]+)\/cancel$/, handler: handleCancelWorkflow },
      { method: 'GET', pattern: /^\/api\/triggers$/, handler: handleGetTriggers },
      { method: 'GET', pattern: /^\/api\/audit\/logs$/, handler: handleGetAuditLogs },
      { method: 'GET', pattern: /^\/api\/security\/status$/, handler: handleGetSecurityStatus },
      { method: 'GET', pattern: /^\/api\/capabilities$/, handler: handleGetCapabilities },
      { method: 'POST', pattern: /^\/api\/chat$/, handler: handleChat },
      { method: 'GET', pattern: /^\/api\/models$/, handler: handleGetModels },
      { method: 'GET', pattern: /^\/api\/config$/, handler: handleGetConfig },
      { method: 'GET', pattern: /^\/api\/config\/quick$/, handler: handleGetQuickConfig },
      { method: 'GET', pattern: /^\/api\/workspace$/, handler: handleGetWorkspace },
      { method: 'GET', pattern: /^\/api\/skills$/, handler: handleGetSkills },
      { method: 'GET', pattern: /^\/api\/channels$/, handler: handleGetChannels },
      { method: 'GET', pattern: /^\/api\/stats\/usage$/, handler: handleGetStatsUsage },
      { method: 'GET', pattern: /^\/api\/plugins\/status$/, handler: handleGetPluginsStatus },
    ];

    for (const route of routes) {
      const methods = Array.isArray(route.method) ? route.method : [route.method];
      if (!methods.includes(req.method || 'GET')) continue;

      const match = path.match(route.pattern);
      if (match) {
        try {
          route.handler(req, res, ...match.slice(1));
        } catch (error) {
          console.error('[MockServer] Handler error:', error);
          sendError(res, 'Internal server error', 500);
        }
        return;
      }
    }

    // No route matched
    sendError(res, 'Not found', 404);
  }

  // === WebSocket Handler ===

  function handleWebSocket(ws: WebSocket): void {
    connectedClients.add(ws);

    ws.on('message', (data: RawData) => {
      try {
        const message = JSON.parse(data.toString());

        if (message.type === 'req') {
          handleWsRequest(ws, message);
        }
      } catch (error) {
        console.error('[MockServer] WebSocket message parse error:', error);
      }
    });

    ws.on('close', () => {
      connectedClients.delete(ws);
    });

    ws.on('error', (error) => {
      console.error('[MockServer] WebSocket error:', error);
      connectedClients.delete(ws);
    });

    // Send challenge after a short delay
    setTimeout(() => {
      if (ws.readyState === WebSocket.OPEN) {
        const nonce = `nonce-${Date.now()}-${Math.random().toString(36).slice(2)}`;
        ws.send(JSON.stringify({
          type: 'event',
          event: 'connect.challenge',
          payload: { nonce },
        }));
      }
    }, challengeDelay);
  }

  function handleWsRequest(ws: WebSocket, message: { id: string; method: string; params?: unknown }): void {
    if (message.method === 'connect') {
      // Handle connect handshake
      setTimeout(() => {
        if (ws.readyState === WebSocket.OPEN) {
          ws.send(JSON.stringify({
            type: 'res',
            id: message.id,
            ok: true,
            payload: {
              sessionId: `session-${Date.now()}`,
              protocolVersion: 3,
              serverVersion: version,
            },
          }));
        }
      }, connectionDelay);
    } else if (message.method === 'health') {
      ws.send(JSON.stringify({
        type: 'res',
        id: message.id,
        ok: true,
        payload: { version, status: 'ok' },
      }));
    } else if (message.method === 'status') {
      ws.send(JSON.stringify({
        type: 'res',
        id: message.id,
        ok: true,
        payload: {
          uptime: Math.floor(process.uptime()),
          connections: connectedClients.size,
          version,
        },
      }));
    } else {
      // Unknown method
      ws.send(JSON.stringify({
        type: 'res',
        id: message.id,
        ok: false,
        error: { code: 'METHOD_NOT_FOUND', message: `Unknown method: ${message.method}` },
      }));
    }
  }

  // === Helper Functions ===

  function sendJson(res: ServerResponse, data: unknown, statusCode = 200): void {
    res.writeHead(statusCode, { 'Content-Type': 'application/json' });
    res.end(JSON.stringify(data));
  }

  function sendError(res: ServerResponse, message: string, statusCode = 500): void {
    res.writeHead(statusCode, { 'Content-Type': 'application/json' });
    res.end(JSON.stringify({ error: { message, code: statusCode } }));
  }

  function parseBody<T>(req: IncomingMessage, callback: (body: T) => void): void {
    let body = '';
    req.on('data', (chunk) => {
      body += chunk.toString();
    });
    req.on('end', () => {
      try {
        const parsed = body ? JSON.parse(body) : {};
        callback(parsed);
      } catch {
        // Send error response if we have access to res
        // This is a simplified version; in real use, pass res to this function
        console.error('[MockServer] Failed to parse request body');
      }
    });
  }

  function simulateStreamEvent(event: string, payload: unknown): void {
    const message = JSON.stringify({ type: 'event', event, payload });
    wsServer?.clients.forEach((ws) => {
      if (ws.readyState === WebSocket.OPEN) {
        ws.send(message);
      }
    });
  }

  function addAuditLogEntry(entry: Omit<MockAuditLogEntry, 'id' | 'timestamp'>): void {
    const logEntry: MockAuditLogEntry = {
      id: `log-${Date.now()}-${Math.random().toString(36).slice(2, 6)}`,
      timestamp: new Date().toISOString(),
      ...entry,
    };
    auditLogs.unshift(logEntry); // Add to beginning for reverse chronological order
    // Keep only last 1000 logs
    if (auditLogs.length > 1000) {
      auditLogs = auditLogs.slice(0, 1000);
    }
  }

  function calculateSecurityLevel(enabledCount: number, totalCount: number): 'critical' | 'high' | 'medium' | 'low' {
    if (totalCount === 0) return 'low';
    const ratio = enabledCount / totalCount;
    if (ratio >= 0.875) return 'critical'; // 14-16 layers
    if (ratio >= 0.625) return 'high';     // 10-13 layers
    if (ratio >= 0.375) return 'medium';   // 6-9 layers
    return 'low';                          // 0-5 layers
  }

  // === Public API ===

  return {
    start: () => {
      return new Promise((resolve, reject) => {
        httpServer = createServer(handleRequest);

        httpServer.on('error', (error: NodeJS.ErrnoException) => {
          if (error.code === 'EADDRINUSE') {
            reject(new Error(`Port ${port} is already in use`));
          } else {
            reject(error);
          }
        });

        httpServer.listen(port, host, () => {
          const address = httpServer?.address();
          actualPort = typeof address === 'object' && address ? address.port : port;

          // Set up WebSocket server
          wsServer = new WebSocketServer({ server: httpServer, path: '/ws' });
          wsServer.on('connection', handleWebSocket);

          console.log(`[MockServer] Started on http://${host}:${actualPort}`);
          console.log(`[MockServer] WebSocket available at ws://${host}:${actualPort}/ws`);
          resolve();
        });
      });
    },

    stop: () => {
      return new Promise((resolve) => {
        // Close all WebSocket connections
        if (wsServer) {
          wsServer.clients.forEach((ws) => {
            ws.close(1000, 'Server shutting down');
          });
          wsServer.close(() => {
            wsServer = null;
          });
        }

        if (httpServer) {
          httpServer.close(() => {
            console.log('[MockServer] Stopped');
            httpServer = null;
            resolve();
          });
        } else {
          resolve();
        }
      });
    },

    getPort: () => actualPort,
    getWsUrl: () => `ws://${host}:${actualPort}/ws`,
    getHttpUrl: () => `http://${host}:${actualPort}`,

    reset: () => {
      hands = [...DEFAULT_HANDS];
      workflows = [...DEFAULT_WORKFLOWS];
      triggers = [...DEFAULT_TRIGGERS];
      agents = [...DEFAULT_AGENTS];
      securityLayers = [...DEFAULT_SECURITY_LAYERS];
      auditLogs = [];
      handRuns.clear();
      workflowRuns.clear();
    },

    setHands: (newHands: MockHand[]) => {
      hands = newHands;
    },

    setWorkflows: (newWorkflows: MockWorkflow[]) => {
      workflows = newWorkflows;
    },

    setTriggers: (newTriggers: MockTrigger[]) => {
      triggers = newTriggers;
    },

    setAgents: (newAgents: MockAgent[]) => {
      agents = newAgents;
    },

    setSecurityLayers: (newLayers: MockSecurityLayer[]) => {
      securityLayers = newLayers;
    },

    addAuditLog: (entry: Omit<MockAuditLogEntry, 'id' | 'timestamp'>) => {
      addAuditLogEntry(entry);
    },

    simulateStreamEvent: (event: string, payload: unknown) => {
      const message = JSON.stringify({ type: 'event', event, payload });
      wsServer?.clients.forEach((ws) => {
        if (ws.readyState === WebSocket.OPEN) {
          ws.send(message);
        }
      });
    },

    getConnectedClients: () => connectedClients.size,
  };
}

// === Export for CommonJS compatibility ===

export default createOpenFangMockServer;