//go:build mysql

package mysql

import (
	"database/sql"
	"fmt"
	"os"
	"path/filepath"
	"runtime"
	"testing"
	"time"

	"github.com/pressly/goose/v3"
	"github.com/stretchr/testify/require"
	"gorm.io/driver/mysql"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
)

type MySQLTestConfig struct {
	Host     string
	Port     int
	User     string
	Password string
	Database string
}

func getMySQLTestConfig() *MySQLTestConfig {
	return &MySQLTestConfig{
		Host:     getEnvOrDefault("NEX_TEST_MYSQL_HOST", "localhost"),
		Port:     getEnvOrDefaultInt("NEX_TEST_MYSQL_PORT", 13306),
		User:     getEnvOrDefault("NEX_TEST_MYSQL_USER", "nex_test"),
		Password: getEnvOrDefault("NEX_TEST_MYSQL_PASSWORD", "testpass"),
		Database: getEnvOrDefault("NEX_TEST_MYSQL_DATABASE", "nex_test"),
	}
}

func getEnvOrDefault(key, defaultValue string) string {
	if value := os.Getenv(key); value != "" {
		return value
	}
	return defaultValue
}

func getEnvOrDefaultInt(key string, defaultValue int) int {
	if value := os.Getenv(key); value != "" {
		var intValue int
		if _, err := fmt.Sscanf(value, "%d", &intValue); err == nil {
			return intValue
		}
	}
	return defaultValue
}

func SkipIfMySQLUnavailable(t *testing.T) {
	t.Helper()

	cfg := getMySQLTestConfig()
	dsn := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?charset=utf8mb4&parseTime=true&loc=Local",
		cfg.User, cfg.Password, cfg.Host, cfg.Port, cfg.Database)

	db, err := sql.Open("mysql", dsn)
	if err != nil {
		t.Skipf("MySQL 不可用: %v", err)
	}
	defer db.Close()

	if err := db.Ping(); err != nil {
		t.Skipf("MySQL 不可用: %v", err)
	}
}

func SetupMySQLTestDB(t *testing.T) *gorm.DB {
	t.Helper()

	SkipIfMySQLUnavailable(t)

	cfg := getMySQLTestConfig()
	dsn := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?charset=utf8mb4&parseTime=true&loc=Local",
		cfg.User, cfg.Password, cfg.Host, cfg.Port, cfg.Database)

	db, err := gorm.Open(mysql.Open(dsn), &gorm.Config{
		Logger: logger.Default.LogMode(logger.Silent),
	})
	require.NoError(t, err, "连接 MySQL 失败")

	if err := runMigrations(db); err != nil {
		require.NoError(t, err, "运行迁移失败")
	}

	if err := cleanupTables(db); err != nil {
		require.NoError(t, err, "清理表数据失败")
	}

	sqlDB, err := db.DB()
	require.NoError(t, err)
	sqlDB.SetMaxIdleConns(10)
	sqlDB.SetMaxOpenConns(100)
	sqlDB.SetConnMaxLifetime(time.Hour)

	t.Cleanup(func() {
		time.Sleep(50 * time.Millisecond)
		sqlDB, err := db.DB()
		if err == nil {
			sqlDB.Close()
		}
	})

	return db
}

func cleanupTables(db *gorm.DB) error {
	if err := db.Exec("SET FOREIGN_KEY_CHECKS = 0").Error; err != nil {
		return err
	}
	if err := db.Exec("TRUNCATE TABLE usage_stats").Error; err != nil {
		return err
	}
	if err := db.Exec("TRUNCATE TABLE models").Error; err != nil {
		return err
	}
	if err := db.Exec("TRUNCATE TABLE providers").Error; err != nil {
		return err
	}
	if err := db.Exec("SET FOREIGN_KEY_CHECKS = 1").Error; err != nil {
		return err
	}
	return nil
}

func runMigrations(db *gorm.DB) error {
	sqlDB, err := db.DB()
	if err != nil {
		return err
	}

	migrationsDir := getMigrationsDir()
	if _, err := os.Stat(migrationsDir); os.IsNotExist(err) {
		return fmt.Errorf("迁移目录不存在: %s", migrationsDir)
	}

	goose.SetDialect("mysql")
	if err := goose.Up(sqlDB, migrationsDir); err != nil {
		return err
	}

	return nil
}

func getMigrationsDir() string {
	_, filename, _, ok := runtime.Caller(0)
	if ok {
		dir := filepath.Join(filepath.Dir(filename), "..", "..", "migrations", "mysql")
		if abs, err := filepath.Abs(dir); err == nil {
			return abs
		}
	}
	return "./migrations/mysql"
}