const express = require('express');
const { spawn, execSync } = require('child_process');
const path = require('path');
const fs = require('fs');
const os = require('os');

const app = express();
app.use(express.json({ limit: '10mb' }));
app.use(express.static(path.join(__dirname, 'public')));

// Resolve claude binary
let CLAUDE_BIN = 'claude';
{
    const local = '/app/claude-bin/node_modules/.bin/claude';
    if (fs.existsSync(local)) {
        CLAUDE_BIN = local;
    } else {
        try {
            CLAUDE_BIN = execSync('which claude 2>/dev/null || echo claude', { encoding: 'utf8' }).trim();
        } catch (e) {}
    }
}
console.log(`✓ Claude binary: ${CLAUDE_BIN}`);

const MODELS = {
    sonnet: 'claude-sonnet-4-6',
    haiku: 'claude-haiku-4-5-20251001',
};

app.post('/api/chat', (req, res) => {
    const { text, model = 'sonnet' } = req.body;
    if (!text?.trim()) return res.status(400).json({ error: 'text required' });

    const modelId = MODELS[model] || MODELS.sonnet;
    const configDir = process.env.CLAUDE_CONFIG_DIR || path.join(os.homedir(), '.claude');

    res.setHeader('Content-Type', 'text/event-stream');
    res.setHeader('Cache-Control', 'no-cache');
    res.setHeader('Connection', 'keep-alive');

    const env = { ...process.env, CLAUDE_CONFIG_DIR: configDir };

    const proc = spawn(CLAUDE_BIN, ['-p', text, '--model', modelId, '--output-format', 'text'], {
        env,
        stdio: ['ignore', 'pipe', 'pipe'],
    });

    proc.stdout.on('data', (chunk) => {
        res.write(`data: ${JSON.stringify({ text: chunk.toString() })}\n\n`);
    });

    let stderrBuf = '';
    proc.stderr.on('data', (chunk) => {
        const s = chunk.toString();
        stderrBuf += s;
        console.error('[claude stderr]', s.substring(0, 500));
    });

    proc.on('error', (err) => {
        console.error('[spawn error]', err.message);
        res.write(`data: ${JSON.stringify({ error: `spawn: ${err.message}` })}\n\n`);
    });

    proc.on('close', (code, signal) => {
        console.log(`[claude close] code=${code} signal=${signal} stderr=${stderrBuf.substring(0,300)}`);
        if (code !== 0) {
            const msg = stderrBuf.trim() || `code=${code} signal=${signal}`;
            res.write(`data: ${JSON.stringify({ error: msg.substring(0, 500) })}\n\n`);
        }
        res.write('data: [DONE]\n\n');
        res.end();
    });

    let finished = false;
    proc.on('close', () => { finished = true; });
    res.on('close', () => { if (!finished) try { proc.kill(); } catch (e) {} });
});

app.listen(8108, () => console.log('sechenov :8108'));