package database

import (
	"database/sql"
	"fmt"
	"log"

	_ "github.com/lib/pq"

	"git.gobha.me/xcaliber/chat-switchboard/config"
)

// DB is the application-wide database connection pool.
var DB *sql.DB

// Connect opens a connection pool to PostgreSQL using the
// DATABASE_URL from config. It pings to verify connectivity.
func Connect(cfg *config.Config) error {
	if cfg.DatabaseURL == "" {
		log.Println("⚠ DATABASE_URL not set — running without database")
		return nil
	}

	var err error
	DB, err = sql.Open("postgres", cfg.DatabaseURL)
	if err != nil {
		return fmt.Errorf("database open: %w", err)
	}

	// Connection pool tuning
	DB.SetMaxOpenConns(25)
	DB.SetMaxIdleConns(5)

	if err := DB.Ping(); err != nil {
		return fmt.Errorf("database ping: %w", err)
	}

	log.Println("✅ Database connected")
	return nil
}

// Close gracefully shuts down the connection pool.
func Close() {
	if DB != nil {
		DB.Close()
	}
}

// IsConnected returns true if a database connection is available.
func IsConnected() bool {
	if DB == nil {
		return false
	}
	return DB.Ping() == nil
}