package dbpool

import (
	"context"
	"fmt"
	"time"

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

type PoolConfig struct {
	MaxOpenConns          int
	MinIdleConns          int
	MaxConnLifetime       time.Duration
	MaxConnIdleTime       time.Duration
	HealthCheckPeriod     time.Duration
	ConnectionAcquireWait time.Duration
}

func NewPostgresPool(ctx context.Context, databaseURL string, pool PoolConfig) (*pgxpool.Pool, error) {
	cfg, err := pgxpool.ParseConfig(databaseURL)
	if err != nil {
		return nil, fmt.Errorf("parse postgres pool config: %w", err)
	}

	if pool.MaxOpenConns <= 0 {
		pool.MaxOpenConns = 25
	}
	if pool.MinIdleConns < 0 {
		pool.MinIdleConns = 0
	}
	if pool.MinIdleConns > pool.MaxOpenConns {
		pool.MinIdleConns = pool.MaxOpenConns
	}
	if pool.MaxConnLifetime <= 0 {
		pool.MaxConnLifetime = 30 * time.Minute
	}
	if pool.MaxConnIdleTime <= 0 {
		pool.MaxConnIdleTime = 5 * time.Minute
	}
	if pool.HealthCheckPeriod <= 0 {
		pool.HealthCheckPeriod = time.Minute
	}
	if pool.ConnectionAcquireWait <= 0 {
		pool.ConnectionAcquireWait = 10 * time.Second
	}

	cfg.MaxConns = int32(pool.MaxOpenConns)
	cfg.MinConns = int32(pool.MinIdleConns)
	cfg.MaxConnLifetime = pool.MaxConnLifetime
	cfg.MaxConnIdleTime = pool.MaxConnIdleTime
	cfg.HealthCheckPeriod = pool.HealthCheckPeriod

	pingCtx, cancel := context.WithTimeout(ctx, pool.ConnectionAcquireWait)
	defer cancel()

	poolConn, err := pgxpool.NewWithConfig(ctx, cfg)
	if err != nil {
		return nil, fmt.Errorf("open postgres pool: %w", err)
	}

	if err := poolConn.Ping(pingCtx); err != nil {
		poolConn.Close()
		return nil, fmt.Errorf("ping postgres: %w", err)
	}

	return poolConn, nil
}