package db

import (
	"context"
	"fmt"
	"log"
	"os"

	"github.com/jackc/pgx/v5/pgxpool"
	"github.com/joho/godotenv"
)

var Pool *pgxpool.Pool

func InitDB() {
	err := godotenv.Load()
	if err != nil {
		log.Fatalf("Error loading .env file: %v", err)
	}

	connString := fmt.Sprintf("postgresql://%s:%s@%s:%s/%s",
		os.Getenv("DB_USER"),
		os.Getenv("DB_PASSWORD"),
		os.Getenv("DB_HOST"),
		os.Getenv("DB_PORT"),
		os.Getenv("DB_NAME"),
	)

	ctx := context.Background()

	config, err := pgxpool.ParseConfig(connString)
	if err != nil {
		log.Fatalf("Unable to parse database config: %v", err)
	}

	Pool, err = pgxpool.NewWithConfig(ctx, config)
	if err != nil {
		log.Fatalf("Unable to create connection pool: %v", err)
	}

	err = Pool.Ping(ctx)
	if err != nil {
		log.Fatalf("Unable to ping database: %v", err)
	}

	fmt.Println("Database connection established successfully")

	if err := CreateTables(); err != nil {
		log.Fatalf("Failed to create tables: %v", err)
	}
}

func CreateTables() error {
	ctx := context.Background()

	_, err := Pool.Exec(ctx, `
		CREATE TABLE IF NOT EXISTS users (
			id SERIAL PRIMARY KEY,
			username VARCHAR(50) UNIQUE NOT NULL,
			email VARCHAR(255) UNIQUE NOT NULL,
			password_hash VARCHAR(255) NOT NULL,
			is_verified BOOLEAN DEFAULT FALSE,
			created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP
		);
		
		CREATE TABLE IF NOT EXISTS verification_codes (
			id SERIAL PRIMARY KEY,
			user_id INT REFERENCES users(id) ON DELETE CASCADE,
			code VARCHAR(6) NOT NULL,
			expires_at TIMESTAMP WITH TIME ZONE NOT NULL,
			used BOOLEAN DEFAULT FALSE,
			created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP
		);
		
		CREATE TABLE IF NOT EXISTS messages (
			id SERIAL PRIMARY KEY,
			sender_id INT REFERENCES users(id),
			receiver_id INT REFERENCES users(id),
			content TEXT NOT NULL,
			sent_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP
		);
	`)

	return err
}
func Close() {
	if Pool != nil {
		Pool.Close()
	}
}