package config

import (
	"fmt"

	"github.com/spf13/viper"
	"github.com/subosito/gotenv"
)

// ServerConfig 服务器配置
type ServerConfig struct {
	Port        string `mapstructure:"port"`
	Environment string `mapstructure:"environment"`
}

// DatabaseConfig 数据库配置
type DatabaseConfig struct {
	Driver string `mapstructure:"driver"`
	SQLite struct {
		Path string `mapstructure:"path"`
	} `mapstructure:"sqlite"`
	Postgres struct {
		Host     string `mapstructure:"host"`
		Port     string `mapstructure:"port"`
		User     string `mapstructure:"user"`
		Password string `mapstructure:"password"`
		DBName   string `mapstructure:"dbname"`
		SSLMode  string `mapstructure:"sslmode"`
	} `mapstructure:"postgres"`
}

// JWTConfig JWT 配置
type JWTConfig struct {
	Secret string `mapstructure:"secret"`
	Expire int    `mapstructure:"expire"`
}

// AppConfig 应用程序配置
type AppConfig struct {
	Server   ServerConfig   `mapstructure:"server"`
	Database DatabaseConfig `mapstructure:"database"`
	JWT      JWTConfig      `mapstructure:"jwt"`
}

// 全局配置变量
var appConfig AppConfig

// LoadConfig 加载配置
func LoadConfig() {
	// 使用 gotenv 加载 .env 文件
	if err := gotenv.Load(); err != nil {
		fmt.Printf("警告: 未找到 .env 文件: %v\n", err)
	}

	// 配置 Viper 以读取 YAML 配置文件
	viper.SetConfigName("config")
	viper.SetConfigType("yaml")
	viper.AddConfigPath(".")
	viper.AddConfigPath("./config")
	viper.AddConfigPath("../")
	if err := viper.MergeInConfig(); err != nil {
		fmt.Printf("警告: 未找到配置文件，使用默认值: %v\n", err)
	}

	// 环境变量前缀
	viper.SetEnvPrefix("TRACE")
	viper.AutomaticEnv()

	// 默认配置
	viper.SetDefault("server.port", "3000")
	viper.SetDefault("server.environment", "development")
	viper.SetDefault("database.driver", "sqlite")
	viper.SetDefault("database.sqlite.path", "./data/database.sqlite")
	viper.SetDefault("database.postgres.host", "localhost")
	viper.SetDefault("database.postgres.port", "5432")
	viper.SetDefault("database.postgres.user", "trace")
	viper.SetDefault("database.postgres.password", "trace123")
	viper.SetDefault("database.postgres.dbname", "trace")
	viper.SetDefault("database.postgres.sslmode", "disable")
	viper.SetDefault("jwt.secret", "your-secret-key-here-change-in-production")
	viper.SetDefault("jwt.expire", 7200)

	// 绑定环境变量（支持无前缀的 .env 文件）
	viper.BindEnv("server.port", "PORT", "TRACE_SERVER_PORT")
	viper.BindEnv("server.environment", "ENVIRONMENT", "TRACE_SERVER_ENVIRONMENT")
	viper.BindEnv("jwt.secret", "JWT_SECRET", "TRACE_JWT_SECRET")
	viper.BindEnv("jwt.expire", "JWT_EXPIRE", "TRACE_JWT_EXPIRE")
	viper.BindEnv("database.driver", "DATABASE_DRIVER", "TRACE_DATABASE_DRIVER")
	viper.BindEnv("database.sqlite.path", "DATABASE_PATH", "TRACE_DATABASE_SQLITE_PATH")
	viper.BindEnv("database.postgres.host", "POSTGRES_HOST", "TRACE_DATABASE_POSTGRES_HOST")
	viper.BindEnv("database.postgres.port", "POSTGRES_PORT", "TRACE_DATABASE_POSTGRES_PORT")
	viper.BindEnv("database.postgres.user", "POSTGRES_USER", "TRACE_DATABASE_POSTGRES_USER")
	viper.BindEnv("database.postgres.password", "POSTGRES_PASSWORD", "TRACE_DATABASE_POSTGRES_PASSWORD")
	viper.BindEnv("database.postgres.dbname", "POSTGRES_DB", "TRACE_DATABASE_POSTGRES_DBNAME")
	viper.BindEnv("database.postgres.sslmode", "POSTGRES_SSLMODE", "TRACE_DATABASE_POSTGRES_SSLMODE")

	// 解析配置
	if err := viper.Unmarshal(&appConfig); err != nil {
		fmt.Printf("配置解析失败: %v\n", err)
	}

	// 验证 JWT 密钥
	if appConfig.JWT.Secret == "your-secret-key-here-change-in-production" {
		fmt.Println("警告: 使用默认 JWT 密钥，请在生产环境中设置 JWT_SECRET 环境变量")
	}

	// 调试打印
	fmt.Printf("加载的配置 - 环境: %s\n", appConfig.Server.Environment)
	fmt.Printf("加载的配置 - 数据库驱动: %s\n", appConfig.Database.Driver)
}

// GetAppConfig 获取应用程序配置
func GetAppConfig() *AppConfig {
	return &appConfig
}