package middleware

import (
	"awesomeProject/internal/common"
	jwtutil "awesomeProject/pkg/utils"
	"github.com/gin-gonic/gin"
	"net/http"
	"strings"
)

// Whitelist 白名单路径（支持通配符）
var Whitelist = []string{
	"/back/file/**",
	"/back/login",
}

func CORSMiddleware() gin.HandlerFunc {
	return func(c *gin.Context) {
		c.Header("Access-Control-Allow-Origin", "*")
		c.Header("Access-Control-Allow-Methods", "*")
		c.Header("Access-Control-Allow-Headers", "*")
		if c.Request.Method == "OPTIONS" {
			c.AbortWithStatus(http.StatusNoContent)
			return
		}
		c.Next()
	}
}

func JWTMiddleware(c *gin.Context) {
	// ✅ 1. 获取请求路径
	path := c.Request.URL.Path
	if !strings.HasPrefix(path, "/back") {
		c.Next()
		return
	}
	// ✅ 2. 检查是否在白名单中
	for _, rule := range Whitelist {
		if PathMatch(rule, path) {
			c.Next()
			return
		}
	}

	// ✅ 3. 从 Header 中提取 Token
	tokenString := c.GetHeader("token")
	if tokenString == "" {
		c.AbortWithStatusJSON(http.StatusOK, common.Error(401, "token无效"))
		return
	}

	// ✅ 4. 解析并验证 Token
	claims, err := jwtutil.ParseTokenToMap(tokenString)
	if err != nil {
		c.AbortWithStatusJSON(http.StatusOK, common.Error(401, "token无效"))
		return
	}

	// ✅ 5. Token 有效，继续处理
	c.Set("tokenMap", claims)
	c.Next()
}

// PathMatch 判断请求路径是否匹配白名单中的通配符规则
func PathMatch(pattern, path string) bool {
	if pattern == path {
		return true
	}

	if len(pattern) > 0 && pattern[0] == '/' {
		pattern = pattern[1:]
	}
	if len(path) > 0 && path[0] == '/' {
		path = path[1:]
	}

	patternParts := strings.Split(pattern, "/")
	pathParts := strings.Split(path, "/")

	if len(patternParts) > len(pathParts) {
		return false
	}

	for i := 0; i < len(patternParts); i++ {
		p := patternParts[i]
		if p == "**" {
			// 匹配任意多级路径
			return true
		} else if p == "*" {
			// 匹配单级路径
			if i == len(patternParts)-1 {
				return true
			}
			continue
		} else if p != pathParts[i] {
			return false
		}
	}

	// 如果模式完全匹配路径的前缀
	return len(patternParts) == len(pathParts)
}