package db

import (
	"context"
	"fmt"

	"ai-operator/internal/config"
	"github.com/jackc/pgx/v5/pgxpool"
)

func OpenPool(ctx context.Context, cfg config.DatabaseConfig) (*pgxpool.Pool, error) {
	if cfg.URL == "" {
		return nil, fmt.Errorf("DATABASE_URL is required")
	}
	pc, err := pgxpool.ParseConfig(cfg.URL)
	if err != nil {
		return nil, fmt.Errorf("parse database url: %w", err)
	}
	pc.MaxConns = int32(cfg.MaxOpenConns)
	pc.MinConns = 0
	pc.MaxConnLifetime = cfg.ConnMaxLifetime
	pool, err := pgxpool.NewWithConfig(ctx, pc)
	if err != nil {
		return nil, fmt.Errorf("open db pool: %w", err)
	}
	if err := pool.Ping(ctx); err != nil {
		pool.Close()
		return nil, fmt.Errorf("db ping: %w", err)
	}
	return pool, nil
}