import asyncio
import gradio as gr
from sqlalchemy.exc import SQLAlchemyError
from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession
from sqlalchemy.future import select
from sqlalchemy.orm import sessionmaker
import logging
import os
import sys
from typing import List, Dict, Any

# Global variables for database session and engine
db_session = None
engine = None
monitoring_task = None
logger = logging.getLogger(__name__)

# Function for dynamically setting the database connection
async def set_db_connection(host: str, port: str, user: str, password: str, db_name: str):
    global db_session, engine
    try:
        engine = create_async_engine(f"mysql+aiomysql://{user}:{password}@{host}:{port}/{db_name}", echo=False)
        Session = sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)
        db_session = Session()
        return "Database connection established."
    except Exception as e:
        logger.error(f"Failed to establish database connection: {e}")
        return f"Failed to connect to database: {e}"

# Periodic feed updater with error handling and logging improvements
async def periodic_update_with_error_handling():
    while True:
        try:
            await asyncio.sleep(300)  # Wait for 5 minutes before updating the feed content.
            await update_feed_content()  # Update the feed content.
        except Exception as e:  # Catch all exceptions for logging purposes.
            logger.error(f"Error in periodic update: {e}")  # Improved logging message format.

# Function to fetch RSS feed content from the provided URL with error handling and logging improvements.
async def fetch_feed_content(feed_url: str) -> Dict[str, Any]:
    try:
        result = await db_session.execute(select(Article).order_by(Article.timestamp.desc()).limit(20))
        articles = result.scalars().all()  # Fetch latest articles
        feed = {
            'title': 'Website Changes Feed',
            'link': feed_url,
            'description': 'Feed of changes detected on monitored websites.',
            'items': [{'title': article.title, 'link': article.url, 'description': article.content, 'pubDate': str(article.timestamp)} for article in articles] if articles else []
        }
        return feed
    except Exception as e:
        logger.error(f"Error fetching feed content: {e}")
        return {}

# Main application that runs Gradio UI and background tasks
async def main():
    global db_session, monitoring_task
    engine = None
    demo = gr.Blocks()
    # Define the Gradio interface
    with demo:
        gr.Markdown("# Website Monitor and Chatbot")
        with gr.Row():
            with gr.Column():
                gr.Markdown("## Database Settings")
                db_host = gr.Textbox(label="Database Host", placeholder="localhost", value="localhost")
                db_port = gr.Textbox(label="Database Port", placeholder="3306", value="3306")
                db_user = gr.Textbox(label="Database User", placeholder="username", value="")
                db_pass = gr.Textbox(label="Database Password", placeholder="password", type="password", value="")
                db_name = gr.Textbox(label="Database Name", placeholder="database_name", value="monitoring")
                db_status_textbox = gr.Textbox(label="Database Status", interactive=False)
                status_text = gr.Textbox(label="Status", interactive=False)
                gr.Markdown("## RSS Feed Reader Settings")
                feed_target_url = gr.Textbox(label="RSS Feed Target URL", placeholder="http://yourwebsite.com/feed")
                view_button = gr.Button("View Feed")
                target_urls = gr.Textbox(label="Target URLs (comma-separated)", placeholder="https://example.com, https://another-site.com")
                storage_location = gr.Textbox(label="Storage Location (CSV file path)", placeholder="/path/to/your/file.csv")
                feed_rss_checkbox = gr.Checkbox(label="Enable RSS Feed")
                start_button = gr.Button("Start Monitoring")
                stop_button = gr.Button("Stop Monitoring")
            with gr.Column():
                feed_content = gr.JSON(label="RSS Feed Content")
                chatbot_interface = gr.Chatbot(type='messages')
                message_input = gr.Textbox(placeholder="Type your message here...")
                send_button = gr.Button("Send")
        # Define button actions
        async def on_start_click(target_urls_str: str, storage_loc: str, feed_enabled: bool, host: str, port: str, user: str, password: str, db_name: str):
            global monitoring_task
            urls = [url.strip() for url in target_urls_str.split(",")]
            await set_db_connection(host, port, user, password, db_name)
            monitoring_task = asyncio.create_task(start_monitoring(urls, storage_loc, feed_enabled))
            return "Monitoring started."
        async def on_stop_click():
            global monitoring_task
            if monitoring_task:
                monitoring_task.cancel()
                monitoring_task = None
            return "Monitoring stopped."
        async def on_view_feed_click(feed_url: str):
            return await fetch_feed_content(feed_url)
        stop_button.click(on_stop_click, outputs=[status_text])
        view_button.click(on_view_feed_click, inputs=[feed_target_url], outputs=[feed_content])
        send_button.click(chatbot_response, inputs=[message_input, chatbot_interface], outputs=[chatbot_interface, message_input])
        # Set up the timer for periodic updates
        feed_updater = gr.Timer(interval=300)
        feed_updater.tick(fn=update_feed_content, outputs=feed_content)
        # Load and check database status when the UI is loaded
        demo.load(update_db_status, outputs=db_status_textbox)
        asyncio.create_task(periodic_update_with_error_handling())
        # Launch the Gradio demo
        await demo.launch()

# Launch the app using asyncio
if __name__ == "__main__":
    asyncio.run(main())