package db

import (
	"fmt"
	"log"
	"os"
	"time"

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

var (
	DB *gorm.DB
)

// --------------------
// DATABASE CONNECTION
// --------------------

func Connect() {
	dsn := fmt.Sprintf(
		"host=%s user=%s password=%s dbname=%s port=%s sslmode=disable TimeZone=Asia/Kolkata",
		mustEnv("DB_HOST"),
		mustEnv("DB_USER"),
		mustEnv("DB_PASSWORD"),
		mustEnv("DB_NAME"),
		getEnv("DB_PORT", "5433"),
	)

	var err error
	DB, err = gorm.Open(postgres.Open(dsn), &gorm.Config{})
	if err != nil {
		log.Fatal("❌ Could not connect to database:", err)
	}

	setupDB(DB)
	fmt.Println("✅ Database connected")
}

func setupDB(database *gorm.DB) {
	sqlDB, err := database.DB()
	if err != nil {
		log.Fatal("❌ Failed to get DB from GORM:", err)
	}
	sqlDB.SetMaxIdleConns(100)
	sqlDB.SetMaxOpenConns(1000)
	sqlDB.SetConnMaxLifetime(time.Minute * 5)
}

// --------------------
// DATABASE SHUTDOWN
// --------------------

func CloseDB() {
	if DB == nil {
		return
	}
	sqlDB, err := DB.DB()
	if err != nil {
		log.Println("Error retrieving sql.DB:", err)
		return
	}
	fmt.Println("Connection closed Successfully")
	sqlDB.Close()
}

// --------------------
// ENV HELPERS
// --------------------

func mustEnv(key string) string {
	val := os.Getenv(key)
	if val == "" {
		log.Fatalf("Missing required env variable: %s", key)
	}
	return val
}

func getEnv(key, fallback string) string {
	if val := os.Getenv(key); val != "" {
		return val
	}
	return fallback
}