// SPDX-License-Identifier: GPL-2.0-or-later
// Copyright (C) 2026 Bryan Joshua Pedini

package main

import (
	"context"
	"database/sql"
	"log/slog"
	"os"
	"time"

	_ "github.com/go-sql-driver/mysql"
)

// OpenDB opens the MySQL pool and pings it with a timeout, mirroring the
// Corefile's pool limits. Must be called after the privilege drop.
func OpenDB(logger *slog.Logger, dsn string) *sql.DB {
	db, err := sql.Open("mysql", dsn)
	if err != nil {
		logger.Error("failed to open mysql pool", "error", err)
		os.Exit(1)
	}

	db.SetMaxOpenConns(10)
	db.SetMaxIdleConns(5)
	db.SetConnMaxLifetime(60 * time.Second)

	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()

	if err := db.PingContext(ctx); err != nil {
		logger.Error("failed to reach mysql", "error", err)
		os.Exit(1)
	}

	logger.Info("mysql pool ready")
	return db
}