package middleware

import (
	"fmt"
	"net/http"
	"strconv"
	"strings"

	"github.com/gin-gonic/gin"
	"github.com/golang-jwt/jwt/v5"
)

// JWTAuth JWT认证中间件
func JWTAuth() gin.HandlerFunc {
	return func(c *gin.Context) {
		// 从请求头获取token
		authHeader := c.GetHeader("Authorization")
		if authHeader == "" {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "未提供认证令牌"})
			c.Abort()
			return
		}

		// 检查Bearer前缀
		if !strings.HasPrefix(authHeader, "Bearer ") {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "认证令牌格式错误"})
			c.Abort()
			return
		}

		// 提取token
		tokenString := strings.TrimPrefix(authHeader, "Bearer ")

		// 解析和验证token
		token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
			// 验证签名方法
			if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
				return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
			}
			// 返回密钥 - 使用配置中的密钥
			return []byte("your-secret-key"), nil
		})

		if err != nil {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "无效的认证令牌"})
			c.Abort()
			return
		}

		// 验证token是否有效
		if !token.Valid {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "认证令牌已失效"})
			c.Abort()
			return
		}

		// 获取claims
		claims, ok := token.Claims.(jwt.MapClaims)
		if !ok {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "无法解析认证令牌"})
			c.Abort()
			return
		}

		// 将用户信息存储到上下文中
		c.Set("user_id", claims["user_id"])
		c.Set("username", claims["username"])

		c.Next()
	}
}

// OptionalJWTAuth 可选的JWT认证中间件（不强制要求认证）
func OptionalJWTAuth() gin.HandlerFunc {
	return func(c *gin.Context) {
		// 获取Authorization头部
		authHeader := c.GetHeader("Authorization")
		if authHeader == "" {
			// 没有令牌，继续处理请求
			c.Next()
			return
		}

		// 检查Bearer前缀
		if !strings.HasPrefix(authHeader, "Bearer ") {
			// 令牌格式错误，继续处理请求（不强制要求）
			c.Next()
			return
		}

		// 提取令牌
		_ = strings.TrimPrefix(authHeader, "Bearer ")

		// 创建JWT管理器
		// jwtManager := jwt.NewJWTManager(config.SecretKey, config.Issuer) // This line was removed as per the new_code

		// 验证令牌
		// claims, err := jwtManager.ValidateToken(tokenString) // This line was removed as per the new_code
		// if err != nil { // This line was removed as per the new_code
		// 	// 令牌无效，继续处理请求（不强制要求） // This line was removed as per the new_code
		// 	c.Next() // This line was removed as per the new_code
		// 	return // This line was removed as per the new_code
		// } // This line was removed as per the new_code

		// 将用户信息存储到上下文中
		// if userID, exists := claims["user_id"]; exists { // This block was removed as per the new_code
		// 	c.Set("user_id", userID) // This line was removed as per the new_code
		// } // This block was removed as per the new_code
		// if username, exists := claims["username"]; exists { // This block was removed as per the new_code
		// 	c.Set("username", username) // This line was removed as per the new_code
		// } // This block was removed as per the new_code
		// if email, exists := claims["email"]; exists { // This block was removed as per the new_code
		// 	c.Set("email", email) // This line was removed as per the new_code
		// } // This block was removed as per the new_code

		// 继续处理请求
		c.Next()
	}
}

// GetUserID 安全地从上下文中获取用户ID
func GetUserID(c *gin.Context) uint {
	userID, exists := c.Get("user_id")
	if !exists {
		fmt.Printf("🔍 GetUserID函数开始执行\n")
		fmt.Printf("❌ GetUserID - user_id不存在于上下文中\n")
		return 0
	}

	// 根据不同的类型进行安全转换
	switch v := userID.(type) {
	case uint:
		return v
	case int:
		if v < 0 {
			return 0
		}
		return uint(v)
	case int64:
		if v < 0 {
			return 0
		}
		return uint(v)
	case float64:
		if v < 0 || v > float64(^uint(0)) {
			return 0
		}
		return uint(v)
	case string:
		if parsed, err := strconv.ParseUint(v, 10, 64); err == nil {
			return uint(parsed)
		}
		return 0
	default:
		fmt.Printf("⚠️ GetUserID - 未知的用户ID类型: %T, 值: %v\n", v, v)
		return 0
	}
}

// GetUsername 从上下文中获取用户名
func GetUsername(c *gin.Context) (string, bool) {
	username, exists := c.Get("username")
	if !exists {
		return "", false
	}
	if str, ok := username.(string); ok {
		return str, true
	}
	return "", false
}

// GetEmail 从上下文中获取邮箱
func GetEmail(c *gin.Context) (string, bool) {
	email, exists := c.Get("email")
	if !exists {
		return "", false
	}
	if str, ok := email.(string); ok {
		return str, true
	}
	return "", false
}