server.js

const express = require('express');
const { execFile, spawn } = require('child_process');
const { resolve } = require('path');
const path = require('path');

const app = express();
const PORT = process.env.PORT || 3456;
const CLAUDE_BIN = process.env.CLAUDE_BIN || 'claude';

app.use(express.json());
app.use(express.static(path.join(__dirname, 'public')));

// Startup: verify claude binary
console.log(`[BOOT] Claude binary configured: "${CLAUDE_BIN}"`);
execFile(CLAUDE_BIN, ['--version'], (err, stdout) => {
  if (err) {
    console.error(`[BOOT][FATAL] Cannot find claude CLI: ${err.message}`);
    console.error(`[BOOT] PATH: ${process.env.PATH}`);
  } else {
    console.log(`[BOOT] Claude CLI found: ${stdout.trim()}`);
  }
});

app.post('/api/generate', (req, res) => {
  const reqId = Math.random().toString(36).substring(2, 8);
  const log = (level, msg) => console.log(`[${new Date().toISOString()}][${reqId}][${level}] ${msg}`);

  log('INFO', `Request received - body keys: ${Object.keys(req.body)}`);

  const { prompt } = req.body;

  if (!prompt || typeof prompt !== 'string' || prompt.trim().length === 0) {
    log('WARN', 'Empty or invalid prompt');
    return res.status(400).json({ error: 'Prompt is required' });
  }

  log('INFO', `Prompt (${prompt.length} chars): "${prompt.substring(0, 100)}${prompt.length > 100 ? '...' : ''}"`);

  const args = ['-p', prompt, '--output-format', 'json'];
  log('INFO', `Spawning: ${CLAUDE_BIN} ${args.map(a => a === prompt ? `"<prompt ${prompt.length}ch>"` : a).join(' ')}`);

  const startTime = Date.now();
  let stdoutChunks = [];
  let stderrChunks = [];

  const child = spawn(CLAUDE_BIN, args, {
    timeout: 120000,
    env: process.env,
    stdio: ['ignore', 'pipe', 'pipe']  // stdin closed, capture stdout+stderr
  });

  log('INFO', `Process spawned - PID: ${child.pid}, stdin: ignored`);

  // Watchdog: log if no output after 10s
  const watchdog = setTimeout(() => {
    log('WARN', `No output after 10s - process still running (PID: ${child.pid})`);
  }, 10000);

  child.stdout.on('data', (chunk) => {
    stdoutChunks.push(chunk);
    log('STDOUT', `+${chunk.length} bytes (total: ${stdoutChunks.reduce((s, c) => s + c.length, 0)})`);
  });

  child.stderr.on('data', (chunk) => {
    stderrChunks.push(chunk);
    log('STDERR', chunk.toString().trim());
  });

  child.on('error', (err) => {
    const elapsed = ((Date.now() - startTime) / 1000).toFixed(1);
    log('ERROR', `Process error after ${elapsed}s: ${err.message}`);
    log('ERROR', `Error code: ${err.code || 'N/A'}`);
    if (!res.headersSent) {
      res.status(500).json({ error: `Spawn error: ${err.message}` });
    }
  });

  child.on('close', (code, signal) => {
    clearTimeout(watchdog);
    const elapsed = ((Date.now() - startTime) / 1000).toFixed(1);
    const stdout = Buffer.concat(stdoutChunks).toString();
    const stderr = Buffer.concat(stderrChunks).toString();

    log('INFO', `Process exited - code: ${code}, signal: ${signal}, elapsed: ${elapsed}s`);
    log('INFO', `stdout: ${stdout.length} bytes, stderr: ${stderr.length} bytes`);

    if (code !== 0) {
      log('ERROR', `Non-zero exit code: ${code}`);
      if (stderr) log('ERROR', `stderr content: ${stderr.substring(0, 500)}`);
      if (stdout) log('ERROR', `stdout content: ${stdout.substring(0, 500)}`);
      if (!res.headersSent) {
        res.status(500).json({ error: `CLI exited with code ${code}: ${stderr || stdout || 'No output'}` });
      }
      return;
    }

    log('INFO', `Parsing JSON response...`);

    try {
      const parsed = JSON.parse(stdout);
      log('INFO', `JSON parsed OK - keys: ${Object.keys(parsed).join(', ')}`);

      const result = parsed.result || parsed;
      const resultPreview = typeof result === 'string' ? result.substring(0, 100) : JSON.stringify(result).substring(0, 100);
      log('INFO', `Result preview: "${resultPreview}..."`);

      res.json({ result });
    } catch (parseErr) {
      log('WARN', `JSON parse failed: ${parseErr.message}`);
      log('WARN', `Raw stdout (first 300): ${stdout.substring(0, 300)}`);
      res.json({ result: stdout.trim() });
    }
  });
});

app.get('/api/health', (req, res) => {
  res.json({ status: 'ok', timestamp: new Date().toISOString() });
});

app.listen(PORT, () => {
  console.log(`[BOOT] CLInterface running on http://localhost:${PORT}`);
  console.log(`[BOOT] Static files: ${path.join(__dirname, 'public')}`);
});