"""
Database Migration Script for Research Projects
Creates the research_projects table for cross-device project persistence.
"""

import sys
import os
from pathlib import Path

# Add the backend directory to Python path
backend_dir = Path(__file__).parent.parent
sys.path.insert(0, str(backend_dir))

from sqlalchemy import create_engine, text
from loguru import logger
import traceback

# Import models - ResearchProject uses SubscriptionBase
from models.subscription_models import Base as SubscriptionBase
from models.research_models import ResearchProject
from services.database import DATABASE_URL

def create_research_tables():
    """Create research-related tables."""
    
    try:
        # Create engine
        engine = create_engine(DATABASE_URL, echo=False)
        
        # Create all tables (ResearchProject uses SubscriptionBase, so it will be created)
        logger.info("Creating research projects tables...")
        SubscriptionBase.metadata.create_all(bind=engine)
        logger.info("✅ Research tables created successfully")
        
        # Verify table was created
        display_setup_summary(engine)
        
    except Exception as e:
        logger.error(f"❌ Error creating research tables: {e}")
        logger.error(traceback.format_exc())
        raise

def display_setup_summary(engine):
    """Display a summary of the created tables."""
    
    try:
        with engine.connect() as conn:
            logger.info("\n" + "="*60)
            logger.info("RESEARCH PROJECTS SETUP SUMMARY")
            logger.info("="*60)
            
            # Check if table exists (SQLite)
            check_query = text("""
                SELECT name FROM sqlite_master 
                WHERE type='table' AND name='research_projects'
            """)
            
            result = conn.execute(check_query)
            table_exists = result.fetchone()
            
            if table_exists:
                logger.info("✅ Table 'research_projects' created successfully")
                
                # Get table schema
                schema_query = text("""
                    SELECT sql FROM sqlite_master 
                    WHERE type='table' AND name='research_projects'
                """)
                result = conn.execute(schema_query)
                schema = result.fetchone()
                if schema:
                    logger.info("\n📋 Table Schema:")
                    logger.info(schema[0])
                
                # Check indexes
                indexes_query = text("""
                    SELECT name FROM sqlite_master 
                    WHERE type='index' AND tbl_name='research_projects'
                """)
                result = conn.execute(indexes_query)
                indexes = result.fetchall()
                
                if indexes:
                    logger.info(f"\n📊 Indexes ({len(indexes)}):")
                    for idx in indexes:
                        logger.info(f"  • {idx[0]}")
                
            else:
                logger.warning("⚠️ Table 'research_projects' not found after creation")
            
            logger.info("\n" + "="*60)
            logger.info("NEXT STEPS:")
            logger.info("="*60)
            logger.info("1. The research_projects table is ready for use")
            logger.info("2. Projects will automatically save to database after intent analysis")
            logger.info("3. Users can resume projects from any device")
            logger.info("4. Use the 'My Projects' button to view saved projects")
            logger.info("="*60)
            
    except Exception as e:
        logger.error(f"Error displaying summary: {e}")

def check_existing_table(engine):
    """Check if research_projects table already exists."""
    
    try:
        with engine.connect() as conn:
            check_query = text("""
                SELECT name FROM sqlite_master 
                WHERE type='table' AND name='research_projects'
            """)
            
            result = conn.execute(check_query)
            table_exists = result.fetchone()
            
            if table_exists:
                logger.info("ℹ️ Table 'research_projects' already exists")
                logger.info("   Running migration will ensure schema is up to date...")
                return True
            
            return False
            
    except Exception as e:
        logger.error(f"Error checking existing table: {e}")
        return False

if __name__ == "__main__":
    logger.info("🚀 Starting research projects database migration...")
    
    try:
        # Create engine to check existing table
        engine = create_engine(DATABASE_URL, echo=False)
        
        # Check existing table
        table_exists = check_existing_table(engine)
        
        # Create tables (idempotent - won't recreate if exists)
        create_research_tables()
        
        logger.info("✅ Migration completed successfully!")
        
    except KeyboardInterrupt:
        logger.info("Migration cancelled by user")
        sys.exit(0)
    except Exception as e:
        logger.error(f"❌ Migration failed: {e}")
        traceback.print_exc()
        sys.exit(1)