app.py

import os, zipfile, subprocess, shutil, uuid, requests, traceback
from flask import Flask, request, jsonify, send_file
from flask_cors import CORS

app = Flask(__name__)
# Enable CORS for external HTML Requests!
CORS(app)

def generate_keystore(work_dir):
    keystore_path = os.path.abspath(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

def push_to_appetize(apk_path, api_token):
    """ Upload to appetize platform to stream App inside the web lightweight layer """
    url = "https://api.appetize.io/v1/apps"
    try:
        with open(apk_path, "rb") as app_file:
            files = {"file": app_file}
            headers = {"Authorization": f"Bearer {api_token}"}
            # Data stream params config
            data = { "platform": "android" } 
            resp = requests.post(url, headers=headers, files=files, data=data)
            
        if resp.status_code == 200:
            json_data = resp.json()
            public_key = json_data.get("publicKey", "")
            return f"https://appetize.io/embed/{public_key}?device=pixel7&scale=80&autoplay=true&language=en"
        else:
            return f"API_REJECTED: Status Code {resp.status_code}. Response: {resp.text}"
    except Exception as e:
        return f"REQUEST_FAILED: {str(e)}"


@app.route('/', methods=['GET'])
def index():
    try:
        return send_file('index.html')
    except Exception as e:
        return f"Index File load failed: {str(e)}", 500


@app.route('/upload_project', methods=['POST'])
def build_and_preview_app():
    # Hugging Face Settings/Secrets Fetcher API variable 
    APPETIZE_API_KEY = os.getenv("APPETIZE_API_KEY", "").strip()

    if not APPETIZE_API_KEY:
         return jsonify({'success': False, 'message': 'System Config Error: Hugging Face space variables missing (APPETIZE_API_KEY). Go to space settings and add it!'})

    if 'file' not in request.files: 
        return jsonify({'success': False, 'message': 'No zip file sent with request!'})
    
    file = request.files['file']
    run_id = str(uuid.uuid4())[:8]
    work_dir = os.path.abspath(f"build_{run_id}")
    os.makedirs(work_dir, exist_ok=True)
    
    zip_location = os.path.join(work_dir, "android_code.zip")
    extract_path = os.path.join(work_dir, "src")
    
    try:
        file.save(zip_location)

        with zipfile.ZipFile(zip_location, "r") as zip_ref:
            zip_ref.extractall(extract_path)
        
        project_folder = next((root for root, _, files in os.walk(extract_path) if "gradlew" in files), None)
        
        if not project_folder: 
            return jsonify({'success': False, 'message': 'Missing build code folder, (gradlew format mismatch). Check Zip Content!'})

        subprocess.run(["chmod", "+x", "gradlew"], cwd=project_folder)
        result = subprocess.run(["./gradlew", "assembleRelease", "--no-daemon", "--stacktrace"], 
                               cwd=project_folder, capture_output=True, text=True)
        
        if result.returncode == 0:
            final_unsigned_apk = next((os.path.join(root, fi) 
                                       for root, _, files in os.walk(project_folder) 
                                       for fi in files if fi.endswith(".apk") and "release" in fi), None)
            
            if final_unsigned_apk:
                ks = generate_keystore(work_dir)
                apk_done = os.path.join(work_dir, f"Final_App_{run_id}.apk")
                subprocess.run(["apksigner", "sign", "--ks", ks, "--ks-pass", "pass:android", "--out", apk_done, final_unsigned_apk])
                
                # Request Live url Engine Logic!
                api_response_url = push_to_appetize(apk_done, APPETIZE_API_KEY)
                
                if api_response_url.startswith("http"):
                    return jsonify({'success': True, 'preview_url': api_response_url})
                else:
                    return jsonify({'success': False, 'message': f'Server processed well but Live App Connection failed. Message details from Appetaize: {api_response_url}'})
            else:
                 return jsonify({'success': False, 'message': 'Folder execution built success! However system fails identifying output extension \'.apk\''})
        
        return jsonify({'success': False, 'message': f"Syntax source script syntax/library compile Gradle break:\n\n{result.stderr[-500:]}"})

    except Exception as e:
        # Here Python completely grabs crashes making no screen turns 500 html format errors rather it sends precise data logs inside Response!!
        stacktrace_issue = traceback.format_exc()
        print("INTERNAL BUG EXPOSED:\n" + stacktrace_issue)
        return jsonify({'success': False, 'message': f"Server Backend Fatal Alert: {str(e)} \nView Server Logs."})
        
    finally:
        # House Keeping Data
        if os.path.exists(work_dir):
            try: shutil.rmtree(work_dir)
            except: pass

if __name__ == '__main__':
    # Launch system port standard map rule ! 
    app.run(host='0.0.0.0', port=7860)