import sqlite3
import os
from ..database import db_path
from ..logger import log

def migrate():
    """
    Migration script to upgrade the items table from schema v4 to v5.
    Adds columns: description, connector, size, ocr_text.
    """
    log.info(f"🚀 Starting database migration on {db_path}...")
    
    if not os.path.exists(db_path):
        log.error(f"❌ Database file not found at {db_path}")
        return

    conn = sqlite3.connect(db_path)
    cursor = conn.cursor()
    
    try:
        # Check existing columns
        cursor.execute("PRAGMA table_info(items)")
        columns = [row[1] for row in cursor.fetchall()]
        
        new_columns = [
            ("description", "VARCHAR"),
            ("connector", "VARCHAR"),
            ("size", "VARCHAR"),
            ("ocr_text", "TEXT")
        ]
        
        for col_name, col_type in new_columns:
            if col_name not in columns:
                log.info(f"➕ Adding column '{col_name}' to 'items' table...")
                cursor.execute(f"ALTER TABLE items ADD COLUMN {col_name} {col_type}")
            else:
                log.info(f"✔️ Column '{col_name}' already exists.")
        
        conn.commit()
        log.info("✅ Migration completed successfully.")
        
    except Exception as e:
        log.error(f"❌ Migration failed: {e}")
        conn.rollback()
    finally:
        conn.close()

if __name__ == "__main__":
    migrate()