from flask import Flask, redirect, url_for
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
from flask_login import LoginManager, current_user
from celery import Celery
from config import Config
import redis
import os
import logging
import sys
from pathlib import Path

# Configure logging
logging.basicConfig(
    level=logging.DEBUG,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
    handlers=[logging.StreamHandler(sys.stdout)]
)
logger = logging.getLogger(__name__)

# Initialize extensions
db = SQLAlchemy()
migrate = Migrate()
login = LoginManager()
login.login_view = 'auth.login'
celery = Celery(__name__, broker=Config.CELERY_BROKER_URL)
cache = None  # Initialize later when app context is available

# Set up user loader for Flask-Login
@login.user_loader
def load_user(user_id):
    from .models import User
    return User.query.get(int(user_id))

def create_app(config_class=Config):
    logger.info("Starting application initialization...")
    
    # Create the Flask app
    app = Flask(__name__)
    logger.info("Flask app created")
    
    # Load configuration
    logger.info(f"Loading configuration from {config_class}...")
    app.config.from_object(config_class)
    
    # Ensure instance path exists
    logger.info(f"Ensuring instance path exists: {app.config['INSTANCE_PATH']}")
    Path(app.config['INSTANCE_PATH']).mkdir(parents=True, exist_ok=True)
    app.instance_path = app.config['INSTANCE_PATH']
    
    # Initialize extensions
    logger.info("Initializing SQLAlchemy...")
    db.init_app(app)
    migrate.init_app(app, db)
    
    logger.info("Initializing LoginManager...")
    login.init_app(app)
    
    # Configure Celery
    logger.info("Configuring Celery...")
    celery.conf.update(app.config)
    
    # Initialize Redis cache
    try:
        logger.info(f"Initializing Redis cache with URL: {app.config['CELERY_BROKER_URL']}")
        global cache
        # Only try to connect to Redis if the URL starts with 'redis://'
        if app.config['CELERY_BROKER_URL'].startswith('redis://'):
            cache = redis.Redis.from_url(app.config['CELERY_BROKER_URL'])
            logger.info("Redis cache initialized successfully")
        else:
            logger.info("Not using Redis cache as broker URL is not Redis")
            cache = None
    except Exception as e:
        logger.error(f"Error initializing Redis cache: {e}")
        # Continue without Redis
        cache = None
        logger.info("Continuing without Redis cache")
    
    # Register test blueprint first (this should always work)
    logger.info("Registering test blueprint...")
    try:
        from .routes.test import test_bp
        app.register_blueprint(test_bp)
        logger.info("Test blueprint registered successfully")
    except Exception as e:
        logger.error(f"Error registering test blueprint: {e}")
    
    # Register other blueprints
    logger.info("Registering other blueprints...")
    
    # Try to register each blueprint individually
    try:
        logger.info("Importing and registering dashboard blueprint...")
        from .routes.dashboard import dashboard_bp
        app.register_blueprint(dashboard_bp, url_prefix='/dashboard')
        logger.info("Dashboard blueprint registered successfully")
    except Exception as e:
        logger.error(f"Error registering dashboard blueprint: {e}")
    
    try:
        logger.info("Importing and registering API blueprint...")
        from .routes.api import api_bp
        app.register_blueprint(api_bp)
        logger.info("API blueprint registered successfully")
    except Exception as e:
        logger.error(f"Error registering API blueprint: {e}")
    
    try:
        logger.info("Importing and registering compliance blueprint...")
        from .routes.compliance import compliance_bp
        app.register_blueprint(compliance_bp)
        logger.info("Compliance blueprint registered successfully")
    except Exception as e:
        logger.error(f"Error registering compliance blueprint: {e}")
    
    try:
        logger.info("Importing and registering Google Ads blueprint...")
        from .routes.google_ads import google_ads_bp
        app.register_blueprint(google_ads_bp)
        logger.info("Google Ads blueprint registered successfully")
    except Exception as e:
        logger.error(f"Error registering Google Ads blueprint: {e}")
    
    try:
        logger.info("Importing and registering auth blueprint...")
        from .routes.auth import auth_bp
        app.register_blueprint(auth_bp)
        logger.info("Auth blueprint registered successfully")
    except Exception as e:
        logger.error(f"Error registering auth blueprint: {e}")
    
    try:
        logger.info("Importing and registering Facebook Ads blueprint...")
        from .routes.facebook_ads import facebook_ads_bp
        app.register_blueprint(facebook_ads_bp)
        logger.info("Facebook Ads blueprint registered successfully")
    except Exception as e:
        logger.error(f"Error registering Facebook Ads blueprint: {e}")
    
    # Add a simple route directly to the app
    @app.route('/')
    def index():
        if current_user.is_authenticated:
            try:
                return redirect(url_for('dashboard.index'))
            except:
                # Fallback to facebook_ads if dashboard is not available
                return redirect(url_for('facebook_ads.index'))
        else:
            return redirect(url_for('auth.login'))
    
    logger.info("Application initialization complete")
    return app