from flask import Flask
from datetime import datetime

def create_app():
    app = Flask(__name__)
    app.config['SECRET_KEY'] = 'your_secret_key'
    
    # Set max upload size to 10GB for large database backups
    app.config['MAX_CONTENT_LENGTH'] = 10 * 1024 * 1024 * 1024  # 10GB
    
    # Application uses direct MariaDB connections via external_server.conf
    # No SQLAlchemy ORM needed - all database operations use raw SQL

    from app.routes import bp as main_bp, warehouse_bp
    from app.daily_mirror import daily_mirror_bp
    app.register_blueprint(main_bp, url_prefix='/')
    app.register_blueprint(warehouse_bp, url_prefix='/warehouse')
    app.register_blueprint(daily_mirror_bp)

    # Add 'now' function to Jinja2 globals
    app.jinja_env.globals['now'] = datetime.now
    
    # Add license check middleware
    @app.before_request
    def check_license_middleware():
        from flask import session, request, redirect, url_for, flash, render_template
        import os
        import json
        from datetime import datetime
        
        # Skip license check for static files, login page, and superadmin users
        if request.endpoint and (
            request.endpoint == 'static' or
            request.endpoint == 'main.login' or
            request.path.startswith('/static/')
        ):
            return None
        
        # Skip if user is not logged in (will be redirected to login by other means)
        if 'user' not in session:
            return None
        
        # Skip license check for superadmin
        if session.get('role') == 'superadmin':
            return None
        
        # Check license validity
        license_path = os.path.join(app.instance_path, 'app_license.json')
        
        if not os.path.exists(license_path):
            session.clear()
            flash('⚠️ Application License Missing - Please contact your superadmin to generate a license key.', 'danger')
            return redirect(url_for('main.login'))
        
        try:
            with open(license_path, 'r') as f:
                license_data = json.load(f)
            
            valid_until = datetime.strptime(license_data['valid_until'], '%Y-%m-%d')
            
            if datetime.utcnow().date() > valid_until.date():
                session.clear()
                flash(f'⚠️ Application License Expired on {license_data["valid_until"]} - Please contact your superadmin to renew the license.', 'danger')
                return redirect(url_for('main.login'))
        except Exception as e:
            session.clear()
            flash('⚠️ License Validation Error - Please contact your superadmin.', 'danger')
            return redirect(url_for('main.login'))
        
        return None
    
    # Initialize automatic backup scheduler
    from app.backup_scheduler import init_backup_scheduler
    init_backup_scheduler(app)
    print("✅ Automatic backup scheduler initialized")

    return app