/**
 * BOB IDE Backend Server
 * Real terminal execution, command routing, artifact management
 * Will be powered by sov-kernel-monster
 */

import Fastify from 'fastify';
import fastifyWs from '@fastify/websocket';
import fastifyStatic from '@fastify/static';
import { execSync, spawn } from 'child_process';
import { promises as fs } from 'fs';
import path from 'path';
import os from 'os';
import { WasmEngine } from './wasm';
import {
  compileNaturalLanguageToXML,
  controlModelViaXML,
  CompilationMode,
  XMLCompilationRequest,
  ModelControlRequest,
} from './xml-compiler-bridge';

const app = Fastify({ logger: true });
const wasmEngine = new WasmEngine();

// Register plugins
await app.register(fastifyWs);
await app.register(fastifyStatic, {
  root: path.join(process.cwd(), 'dist'),
});

// =====================================================================
// TERMINAL STATE
// =====================================================================

interface TerminalSession {
  id: string;
  cwd: string;
  env: Record<string, string>;
  history: string[];
}

const sessions = new Map<string, TerminalSession>();

function generateSessionId(): string {
  return `term-${Date.now()}-${Math.random().toString(36).slice(2, 9)}`;
}

// =====================================================================
// TERMINAL ENDPOINTS
// =====================================================================

// Create new terminal session
app.post<{ Body: { cols: number; rows: number } }>('/api/terminal/create', async (req) => {
  const sessionId = generateSessionId();
  const session: TerminalSession = {
    id: sessionId,
    cwd: process.cwd(),
    env: { ...process.env },
    history: [],
  };
  sessions.set(sessionId, session);
  return { sessionId, cwd: session.cwd };
});

// Close terminal session
app.delete<{ Params: { id: string } }>('/api/terminal/:id', async (req) => {
  const { id } = req.params;
  sessions.delete(id);
  return { ok: true };
});

// =====================================================================
// COMMAND EXECUTION
// =====================================================================

app.post<{
  Body: { sessionId: string; cmd: string; cwd?: string };
}>('/api/execute', async (req, reply) => {
  const { sessionId, cmd, cwd: newCwd } = req.body;
  const session = sessions.get(sessionId);

  if (!session) {
    reply.status(404).send({ error: 'Session not found' });
    return;
  }

  try {
    // Update working directory if provided
    if (newCwd) session.cwd = newCwd;

    // Add to history
    session.history.push(cmd);

    // Execute command
    const output = execSync(cmd, {
      cwd: session.cwd,
      env: session.env,
      encoding: 'utf-8',
      timeout: 30000,
    }).trim();

    return {
      ok: true,
      output,
      cwd: session.cwd,
      exitCode: 0,
    };
  } catch (error: any) {
    return {
      ok: false,
      output: error.stderr || error.message,
      cwd: session.cwd,
      exitCode: error.status || 1,
      error: error.message,
    };
  }
});

// =====================================================================
// FILE OPERATIONS
// =====================================================================

app.get<{ Params: { path: string } }>('/api/file/*', async (req, reply) => {
  try {
    const filePath = req.params.path;
    const fullPath = path.join(process.cwd(), filePath);

    // Safety: prevent directory traversal
    if (!fullPath.startsWith(process.cwd())) {
      reply.status(403).send({ error: 'Access denied' });
      return;
    }

    const content = await fs.readFile(fullPath, 'utf-8');
    return { content, path: filePath };
  } catch (error: any) {
    reply.status(404).send({ error: error.message });
  }
});

app.post<{ Body: { path: string; content: string } }>('/api/file/write', async (req) => {
  const { path: filePath, content } = req.body;
  const fullPath = path.join(process.cwd(), filePath);

  if (!fullPath.startsWith(process.cwd())) {
    return { error: 'Access denied' };
  }

  try {
    await fs.writeFile(fullPath, content, 'utf-8');
    return { ok: true, path: filePath };
  } catch (error: any) {
    return { error: error.message };
  }
});

// =====================================================================
// WASM ENGINE ENDPOINTS
// =====================================================================

app.post<{ Body: { name: string; wasmBuffer: string } }>('/api/wasm/load', async (req) => {
  const { name, wasmBuffer } = req.body;
  try {
    const buffer = Buffer.from(wasmBuffer, 'base64');
    const contextId = await wasmEngine.loadModule(name, buffer);
    return { ok: true, contextId };
  } catch (error: any) {
    return { error: error.message };
  }
});

app.post<{ Body: { contextId: string; fn: string; args: any[] } }>('/api/wasm/call', async (req) => {
  const { contextId, fn, args } = req.body;
  try {
    const result = await wasmEngine.call(contextId, fn, args);
    return { ok: true, result };
  } catch (error: any) {
    return { error: error.message };
  }
});

app.post<{ Body: { contextId: string; ptr: number; len: number } }>(
  '/api/wasm/read',
  async (req) => {
    const { contextId, ptr, len } = req.body;
    try {
      const data = wasmEngine.readMemory(contextId, ptr, len);
      return { ok: true, data: data.toString('base64') };
    } catch (error: any) {
      return { error: error.message };
    }
  }
);

app.post<{ Body: { contextId: string; ptr: number; data: string } }>(
  '/api/wasm/write',
  async (req) => {
    const { contextId, ptr, data } = req.body;
    try {
      const buffer = Buffer.from(data, 'base64');
      wasmEngine.writeMemory(contextId, ptr, buffer);
      return { ok: true };
    } catch (error: any) {
      return { error: error.message };
    }
  }
);

app.post<{ Body: { contextId: string; size: number } }>('/api/wasm/alloc', async (req) => {
  const { contextId, size } = req.body;
  try {
    const ptr = await wasmEngine.allocate(contextId, size);
    return { ok: true, ptr };
  } catch (error: any) {
    return { error: error.message };
  }
});

app.post<{ Body: { contextId: string; ptr: number } }>('/api/wasm/free', async (req) => {
  const { contextId, ptr } = req.body;
  try {
    await wasmEngine.deallocate(contextId, ptr);
    return { ok: true };
  } catch (error: any) {
    return { error: error.message };
  }
});

app.get<{ Params: { contextId: string } }>('/api/wasm/:contextId/stats', async (req) => {
  const { contextId } = req.params;
  const stats = wasmEngine.getStats(contextId);
  return stats || { error: 'Context not found' };
});

// =====================================================================
// REAL-TIME TERMINAL (WebSocket)
// =====================================================================

app.register(async (fastify) => {
  fastify.get<{ Params: { id: string } }>(
    '/api/terminal/:id/ws',
    { websocket: true },
    (socket, req) => {
      const sessionId = req.params.id;
      const session = sessions.get(sessionId);

      if (!session) {
        socket.send(JSON.stringify({ error: 'Session not found' }));
        socket.close();
        return;
      }

      // Spawn interactive shell
      const shell = spawn('bash', [], {
        cwd: session.cwd,
        env: session.env,
        pty: true,
      });

      socket.on('message', (msg: Buffer) => {
        try {
          const data = JSON.parse(msg.toString());
          if (data.type === 'input') {
            shell.stdin.write(data.data);
          } else if (data.type === 'resize') {
            if (shell.stdin.isTTY) {
              (shell.stdin as any).setRawMode(true);
              (shell.stdin as any).resize(data.cols, data.rows);
            }
          }
        } catch (e) {
          shell.stdin.write(msg);
        }
      });

      shell.stdout.on('data', (data) => {
        socket.send(JSON.stringify({ type: 'output', data: data.toString() }));
      });

      shell.stderr.on('data', (data) => {
        socket.send(JSON.stringify({ type: 'output', data: data.toString() }));
      });

      shell.on('exit', () => {
        socket.send(JSON.stringify({ type: 'exit' }));
        socket.close();
      });

      socket.on('close', () => {
        shell.kill();
      });
    }
  );

  // WASM WebSocket execution
  fastify.get<{ Params: { contextId: string } }>(
    '/api/wasm/:contextId/ws',
    { websocket: true },
    (socket, req) => {
      const { contextId } = req.params;
      wasmEngine.wsHandler(socket, contextId);
    }
  );
});

// =====================================================================
// GREP / SEARCH
// =====================================================================

app.post<{ Body: { pattern: string; path?: string; recursive?: boolean } }>(
  '/api/grep',
  async (req) => {
    const { pattern, path: searchPath = '.', recursive = true } = req.body;

    try {
      const flags = recursive ? '-r' : '';
      const output = execSync(`grep -n ${flags} "${pattern}" "${searchPath}"`, {
        cwd: process.cwd(),
        encoding: 'utf-8',
      }).trim();

      return {
        ok: true,
        results: output
          .split('\n')
          .filter((l) => l)
          .map((line) => {
            const [file, lineNum, ...rest] = line.split(':');
            return { file, lineNum: parseInt(lineNum), content: rest.join(':') };
          }),
      };
    } catch (error: any) {
      if (error.status === 1) {
        return { ok: true, results: [] }; // No matches
      }
      return { error: error.message };
    }
  }
);

// =====================================================================
// CURL / HTTP
// =====================================================================

app.post<{ Body: { url: string; method?: string; headers?: Record<string, string>; body?: string } }>(
  '/api/curl',
  async (req) => {
    const { url, method = 'GET', headers = {}, body } = req.body;

    try {
      let cmd = `curl -s -X ${method}`;
      for (const [k, v] of Object.entries(headers)) {
        cmd += ` -H "${k}: ${v}"`;
      }
      if (body) {
        cmd += ` -d '${body}'`;
      }
      cmd += ` "${url}"`;

      const output = execSync(cmd, {
        encoding: 'utf-8',
        timeout: 30000,
      }).trim();

      return { ok: true, output };
    } catch (error: any) {
      return { error: error.message };
    }
  }
);

// =====================================================================
// BASH
// =====================================================================

app.post<{ Body: { script: string; args?: string[] } }>('/api/bash', async (req) => {
  const { script, args = [] } = req.body;

  try {
    const output = execSync(script, {
      cwd: process.cwd(),
      env: process.env,
      encoding: 'utf-8',
      timeout: 30000,
      shell: '/bin/bash',
    }).trim();

    return { ok: true, output };
  } catch (error: any) {
    return { error: error.message, output: error.stdout || '', stderr: error.stderr || '' };
  }
});

// =====================================================================
// OMEGA SHELL (GUARDED COMMAND EXECUTION)
// =====================================================================

const OMEGA_ALLOWLIST = [
  'PWD', 'LS', 'DIR', 'GIT', 'CARGO', 'LAKE', 'DUNE', 'DOTNET',
  'NIM', 'JQ', 'MAKE', 'CMAKE', 'CLANG', 'LLVM-OBJDUMP', 'LLVM-READOBJ',
  'QEMU-SYSTEM-X86_64', 'GREP', 'CURL', 'BASH', 'SH', 'CAT', 'ECHO',
  'FIND', 'WHICH', 'UNAME', 'WHOAMI', 'CHMOD', 'CHOWN', 'NODE', 'NPM',
  'PYTHON', 'PYTHON3', 'RUBY', 'GO', 'RUSTC', 'CARGO', 'GFORTRAN',
  'GCC', 'G++', 'CLANG++', 'JAVA', 'JAVAC', 'GHCI', 'OCAML',
];

app.post<{ Body: { command: string } }>('/api/omega/run', async (req, reply) => {
  const { command } = req.body;

  if (!command || !command.trim()) {
    reply.status(400).send({ error: 'No command supplied', exitCode: 77 });
    return;
  }

  // Extract first word (command name)
  const firstWord = command.trim().split(/\s+/)[0].toUpperCase();

  // Check allowlist
  if (!OMEGA_ALLOWLIST.includes(firstWord)) {
    return {
      ok: false,
      output: `[OMEGA:SILENCE] command rejected by allowlist: ${firstWord}`,
      error: 'Command not allowed',
      exitCode: 77,
    };
  }

  // Reject shell metacharacters
  const dangerous = ['&&', '||', ';', '|', '>', '<', '`', '$', '&'];
  for (const char of dangerous) {
    if (command.includes(char)) {
      return {
        ok: false,
        output: '[OMEGA:SILENCE] shell metacharacters rejected',
        error: 'Metacharacters not allowed',
        exitCode: 77,
      };
    }
  }

  try {
    const output = execSync(command, {
      cwd: process.cwd(),
      env: process.env,
      encoding: 'utf-8',
      timeout: 30000,
      stdio: 'pipe',
    }).trim();

    return {
      ok: true,
      output,
      error: '',
      exitCode: 0,
    };
  } catch (error: any) {
    return {
      ok: false,
      output: error.stdout || '',
      error: error.stderr || error.message,
      exitCode: error.status || 1,
    };
  }
});

// =====================================================================
// XML COMPILER (NATURAL LANGUAGE → XML PROMPTS)
// =====================================================================

app.post<{ Body: XMLCompilationRequest }>('/api/xml/compile', async (req) => {
  try {
    const result = await compileNaturalLanguageToXML(req.body);
    return {
      ok: true,
      ...result,
    };
  } catch (error: any) {
    return {
      ok: false,
      error: error.message,
    };
  }
});

// Control mini models (Granite, Nemotron, etc.) via XML-derived prompts
app.post<{ Body: ModelControlRequest }>('/api/xml/control-model', async (req) => {
  try {
    const result = await controlModelViaXML(req.body);
    return {
      ok: true,
      ...result,
    };
  } catch (error: any) {
    return {
      ok: false,
      error: error.message,
    };
  }
});

// =====================================================================
// ARTIFACT OPERATIONS
// =====================================================================

app.post<{ Body: { name: string; type: string; content: Buffer } }>(
  '/api/artifact/save',
  async (req) => {
    const { name, type, content } = req.body;
    const artifactDir = path.join(process.cwd(), '.artifacts');

    try {
      await fs.mkdir(artifactDir, { recursive: true });
      const filePath = path.join(artifactDir, `${name}.${type}`);
      await fs.writeFile(filePath, content);

      return { ok: true, path: filePath };
    } catch (error: any) {
      return { error: error.message };
    }
  }
);

app.get<{ Params: { name: string } }>('/api/artifact/:name', async (req, reply) => {
  const { name } = req.params;
  const artifactDir = path.join(process.cwd(), '.artifacts');
  const filePath = path.join(artifactDir, name);

  try {
    const content = await fs.readFile(filePath);
    reply.type('application/octet-stream');
    return content;
  } catch (error: any) {
    reply.status(404).send({ error: error.message });
  }
});

// =====================================================================
// START SERVER
// =====================================================================

const PORT = process.env.PORT || 3000;

try {
  await app.listen({ port: parseInt(String(PORT)), host: '0.0.0.0' });
  console.log(`✅ BOB IDE Backend running on http://localhost:${PORT}`);
} catch (err) {
  app.log.error(err);
  process.exit(1);
}

export default app;