// Converts 3MF files to GLB via the Python/trimesh sidecar, so the browser can
// render Bambu/MakerWorld production-extension 3MFs (which the JS 3MFLoader can't).

const path = require('path');
const { execFile } = require('child_process');

const PYTHON = process.env.PYTHON_BIN || path.join(__dirname, '..', 'tools', 'venv', 'bin', 'python');
const SCRIPT = path.join(__dirname, '..', 'tools', 'convert_3mf.py');

// Returns { glb, volume_cm3, bbox, faces } or throws.
function convert3mfToGlb(inputPath, outputPath) {
  return new Promise((resolve, reject) => {
    execFile(
      PYTHON,
      [SCRIPT, inputPath, outputPath],
      { maxBuffer: 16 * 1024 * 1024, timeout: 120000 },
      (err, stdout, stderr) => {
        if (err) return reject(new Error(stderr ? stderr.split('\n').slice(-3).join(' ') : err.message));
        let result;
        try {
          result = JSON.parse(stdout.trim().split('\n').pop());
        } catch {
          return reject(new Error('Converter returned unparseable output.'));
        }
        if (result.error) return reject(new Error(result.error));
        resolve(result);
      }
    );
  });
}

module.exports = { convert3mfToGlb };