from flask import Flask, request, send_file, Response
import os, zipfile, subprocess, shutil, uuid

app = Flask(__name__)

def generate_keystore(work_dir):
    keystore_path = os.path.join(work_dir, "debug.keystore")
    cmd = ["keytool", "-genkey", "-v", "-keystore", keystore_path, "-storepass", "android", "-alias", "androiddebugkey", "-keypass", "android", "-keyalg", "RSA", "-keysize", "2048", "-validity", "10000", "-dname", "CN=AndroidDebug,O=Android,C=US"]
    subprocess.run(cmd, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
    return keystore_path

@app.route('/')
def index():
    return "Backend is running. Use the HTML interface to upload."

@app.route('/upload', methods=['POST'])
def upload_file():
    if 'file' not in request.files: return "No file", 400
    
    file = request.files['file']
    unique_id = str(uuid.uuid4())[:8]
    work_dir = f"build_{unique_id}"
    os.makedirs(work_dir, exist_ok=True)
    
    zip_path = os.path.join(work_dir, "project.zip")
    extract_path = os.path.join(work_dir, "extract")
    file.save(zip_path)

    try:
        with zipfile.ZipFile(zip_path, "r") as z:
            z.extractall(extract_path)
        
        # Find gradlew
        project_root = next((root for root, _, files in os.walk(extract_path) if "gradlew" in files), None)
        if not project_root: return "Gradlew not found", 400

        gradlew = os.path.join(project_root, "gradlew")
        subprocess.run(["chmod", "+x", gradlew])

        # Build
        build_res = subprocess.run(["./gradlew", "assembleRelease", "--no-daemon"], cwd=project_root, capture_output=True, text=True)
        
        if build_res.returncode == 0:
            unsigned_apk = next((os.path.join(r, f) for r, _, fs in os.walk(project_root) for f in fs if f.endswith(".apk") and "release" in f), None)
            if unsigned_apk:
                ks = generate_keystore(work_dir)
                out_apk = os.path.abspath(os.path.join(work_dir, f"App_{unique_id}.apk"))
                # Sign
                subprocess.run(["apksigner", "sign", "--ks", ks, "--ks-pass", "pass:android", "--out", out_apk, unsigned_apk])
                
                return send_file(out_apk, as_attachment=True, download_name=f"Build_{unique_id}.apk")
        
        return f"Build Failed: {build_res.stderr[:500]}", 500
    finally:
        # Optional: Cleanup folder after some time or immediately
        # shutil.rmtree(work_dir) 
        pass

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=7860)