backend-service/internal/database/database.go

package database

import (
	"fmt"
	"log"

	"attune-heart-therapy/internal/config"
	"attune-heart-therapy/internal/models"

	"gorm.io/driver/postgres"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
)

// DB holds the database connection
type DB struct {
	*gorm.DB
}

// New creates a new database connection
func New(cfg *config.Config) (*DB, error) {
	dsn := fmt.Sprintf(
		"host=%s user=%s password=%s dbname=%s port=%s sslmode=%s TimeZone=UTC",
		cfg.Database.Host,
		cfg.Database.User,
		cfg.Database.Password,
		cfg.Database.Name,
		cfg.Database.Port,
		cfg.Database.SSLMode,
	)

	// Configure GORM logger
	gormConfig := &gorm.Config{
		Logger: logger.Default.LogMode(logger.Info),
	}

	db, err := gorm.Open(postgres.Open(dsn), gormConfig)
	if err != nil {
		return nil, fmt.Errorf("failed to connect to database: %w", err)
	}

	// Configure connection pool
	sqlDB, err := db.DB()
	if err != nil {
		return nil, fmt.Errorf("failed to get underlying sql.DB: %w", err)
	}

	// Set connection pool settings
	sqlDB.SetMaxIdleConns(10)
	sqlDB.SetMaxOpenConns(100)

	log.Println("Successfully connected to PostgreSQL database")

	return &DB{db}, nil
}

// Close closes the database connection
func (db *DB) Close() error {
	sqlDB, err := db.DB.DB()
	if err != nil {
		return err
	}
	return sqlDB.Close()
}

// Migrate runs database migrations
func (db *DB) Migrate() error {
	log.Println("Running database migrations...")

	// Auto-migrate all models
	err := db.AutoMigrate(
		&models.User{},
		&models.Schedule{},
		&models.Booking{},
		&models.Notification{},
	)

	if err != nil {
		return fmt.Errorf("failed to run migrations: %w", err)
	}

	log.Println("Database migrations completed successfully")
	return nil
}

// Seed creates initial data for the database
func (db *DB) Seed() error {
	log.Println("Seeding database with initial data...")

	// Check if we already have data to avoid duplicate seeding
	var userCount int64
	db.Model(&models.User{}).Count(&userCount)

	if userCount > 0 {
		log.Println("Database already contains data, skipping seeding")
		return nil
	}

	// Add any initial data here if needed
	// For now, we'll just log that seeding is complete
	log.Println("Database seeding completed")
	return nil
}

// Health checks database connectivity
func (db *DB) Health() error {
	sqlDB, err := db.DB.DB()
	if err != nil {
		return err
	}
	return sqlDB.Ping()
}