#!/bin/bash

# Script to run Alembic migrations for AudiOhm backend
# Usage: ./run_migration.sh [command]

set -e

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

# Change to backend directory
cd "$(dirname "$0")"

echo -e "${GREEN}=== AudiOhm Alembic Migration Tool ===${NC}\n"

# Check if .env exists
if [ ! -f .env ]; then
    echo -e "${RED}Error: .env file not found!${NC}"
    echo "Please copy .env.example to .env and configure it first."
    exit 1
fi

# Function to show help
show_help() {
    echo "Usage: $0 [command]"
    echo ""
    echo "Commands:"
    echo "  current      Show current migration version"
    echo "  history      Show migration history"
    echo "  heads        Show migration heads"
    echo "  status       Show current status"
    echo "  upgrade      Apply all pending migrations"
    echo "  upgrade+1    Apply next migration only"
    echo "  downgrade-1  Revert last migration"
    echo "  downgrade    Revert all migrations (to base)"
    echo "  show [id]    Show details of a migration"
    echo "  create       Create a new migration (requires -m message)"
    echo "  sql-upgrade  Show SQL for upgrade without executing"
    echo "  sql-downgrade Show SQL for downgrade without executing"
    echo ""
    echo "Examples:"
    echo "  $0 current"
    echo "  $0 upgrade"
    echo "  $0 downgrade-1"
    echo "  $0 create -m 'Add new table'"
    echo "  $0 show 001_add_library_tables"
    echo ""
}

# Function to check if PostgreSQL is running
check_postgres() {
    if ! pg_isready -h localhost -p 5432 > /dev/null 2>&1; then
        echo -e "${YELLOW}Warning: PostgreSQL might not be running${NC}"
        echo "Please start PostgreSQL service first"
        return 1
    fi
    return 0
}

# Parse command
case "$1" in
    current)
        echo "Showing current migration version..."
        check_postgres
        alembic current
        ;;
    history)
        echo "Showing migration history..."
        alembic history
        ;;
    heads)
        echo "Showing migration heads..."
        alembic heads
        ;;
    status)
        echo "Showing migration status..."
        check_postgres
        alembic current
        echo ""
        alembic heads
        ;;
    upgrade)
        echo -e "${YELLOW}Applying all pending migrations...${NC}"
        check_postgres
        alembic upgrade head
        echo -e "${GREEN}✓ Migrations applied successfully!${NC}"
        ;;
    upgrade+1)
        echo -e "${YELLOW}Applying next migration...${NC}"
        check_postgres
        alembic upgrade +1
        echo -e "${GREEN}✓ Migration applied successfully!${NC}"
        ;;
    downgrade-1)
        echo -e "${YELLOW}Reverting last migration...${NC}"
        check_postgres
        alembic downgrade -1
        echo -e "${GREEN}✓ Migration reverted successfully!${NC}"
        ;;
    downgrade)
        echo -e "${RED}WARNING: This will revert ALL migrations!${NC}"
        read -p "Are you sure? (yes/no): " confirm
        if [ "$confirm" = "yes" ]; then
            check_postgres
            alembic downgrade base
            echo -e "${GREEN}✓ All migrations reverted!${NC}"
        else
            echo "Aborted."
        fi
        ;;
    show)
        if [ -z "$2" ]; then
            echo "Error: Please provide a migration ID"
            echo "Usage: $0 show <migration_id>"
            exit 1
        fi
        echo "Showing migration details for: $2"
        alembic show "$2"
        ;;
    create)
        shift
        echo "Creating new migration..."
        alembic revision "$@"
        echo -e "${GREEN}✓ New migration file created!${NC}"
        echo "Edit the file in alembic/versions/ and then run: $0 upgrade"
        ;;
    sql-upgrade)
        echo "Showing SQL for upgrade (not executing)..."
        check_postgres
        alembic upgrade head --sql
        ;;
    sql-downgrade)
        echo "Showing SQL for downgrade (not executing)..."
        check_postgres
        alembic downgrade -1 --sql
        ;;
    help|--help|-h)
        show_help
        ;;
    *)
        echo -e "${RED}Error: Unknown command '$1'${NC}\n"
        show_help
        exit 1
        ;;
esac

echo ""