"""
Database migration script to add template-related fields to generated_content table

Adds:
- formatted_html (Text, nullable)
- template_used (String(50), nullable)
- site_deployment_id (Integer, FK to site_deployments, nullable, indexed)

Usage:
    python scripts/migrate_add_template_fields.py
"""

import sys
from pathlib import Path

project_root = Path(__file__).parent.parent
sys.path.insert(0, str(project_root))

from sqlalchemy import text
from src.database.session import db_manager
from src.core.config import get_config


def migrate():
    """Add template-related fields to generated_content table"""
    print("Starting migration: add template fields to generated_content...")
    
    try:
        config = get_config()
        print(f"Database URL: {config.database.url}")
    except Exception as e:
        print(f"Error loading configuration: {e}")
        sys.exit(1)
    
    try:
        db_manager.initialize()
        engine = db_manager.get_engine()
        
        with engine.connect() as conn:
            print("Checking for existing columns...")
            
            result = conn.execute(text("PRAGMA table_info(generated_content)"))
            existing_columns = [row[1] for row in result]
            print(f"Existing columns: {', '.join(existing_columns)}")
            
            migrations_applied = []
            
            if "formatted_html" not in existing_columns:
                print("Adding formatted_html column...")
                conn.execute(text("ALTER TABLE generated_content ADD COLUMN formatted_html TEXT"))
                migrations_applied.append("formatted_html")
                conn.commit()
            else:
                print("formatted_html column already exists, skipping")
            
            if "template_used" not in existing_columns:
                print("Adding template_used column...")
                conn.execute(text("ALTER TABLE generated_content ADD COLUMN template_used VARCHAR(50)"))
                migrations_applied.append("template_used")
                conn.commit()
            else:
                print("template_used column already exists, skipping")
            
            if "site_deployment_id" not in existing_columns:
                print("Adding site_deployment_id column...")
                conn.execute(text("ALTER TABLE generated_content ADD COLUMN site_deployment_id INTEGER"))
                migrations_applied.append("site_deployment_id")
                conn.commit()
                
                print("Creating index on site_deployment_id...")
                conn.execute(text(
                    "CREATE INDEX IF NOT EXISTS ix_generated_content_site_deployment_id "
                    "ON generated_content(site_deployment_id)"
                ))
                conn.commit()
            else:
                print("site_deployment_id column already exists, skipping")
            
            if migrations_applied:
                print(f"\nMigration complete! Added columns: {', '.join(migrations_applied)}")
            else:
                print("\nNo migrations needed - all columns already exist")
        
    except Exception as e:
        print(f"Error during migration: {e}")
        import traceback
        traceback.print_exc()
        sys.exit(1)
    finally:
        db_manager.close()


if __name__ == "__main__":
    migrate()