package middleware

import (
	"fmt"
	"net/http"
	"strings"
	"time"
	"verification-platform-backend/internal/database"
	"verification-platform-backend/internal/model"
	"verification-platform-backend/pkg/jwt"
	"verification-platform-backend/pkg/response"

	"github.com/gin-gonic/gin"
)

func CheckAppStatus() gin.HandlerFunc {
	return func(c *gin.Context) {
		appKey := c.Param("appKey")
		if appKey == "" {
			c.Next()
			return
		}

		var app model.Application
		if err := database.DB.Where("app_key = ?", appKey).First(&app).Error; err != nil {
			response.Error(c, 404, "应用不存在")
			c.Abort()
			return
		}

		if app.Status == "maintenance" {
			response.Error(c, 503, "应用维护中，暂时无法访问")
			c.Abort()
			return
		}
		if app.Status == "stopped" {
			response.Error(c, 403, "应用已停止运营")
			c.Abort()
			return
		}

		c.Set("app", &app)
		c.Next()
	}
}

// JWT JWT中间件
func JWT() gin.HandlerFunc {
	return func(c *gin.Context) {
		fmt.Printf("JWT中间件被调用: %s %s\n", c.Request.Method, c.Request.URL.Path)

		var token string

		authHeader := c.GetHeader("Authorization")
		if authHeader != "" {
			parts := strings.SplitN(authHeader, " ", 2)
			if len(parts) == 2 && parts[0] == "Bearer" {
				token = parts[1]
			}
		}

		if token == "" {
			token = c.Query("token")
		}

		if token == "" {
			fmt.Printf("JWT中间件: Authorization header is required\n")
			response.Error(c, http.StatusUnauthorized, "Authorization header is required")
			c.Abort()
			return
		}

		claims, err := jwt.ParseToken(token)
		if err != nil {
			fmt.Printf("JWT中间件: Invalid token: %v\n", err)
			response.Error(c, http.StatusUnauthorized, "Invalid token")
			c.Abort()
			return
		}

		if time.Now().Unix() > claims.ExpiresAt.Unix() {
			fmt.Printf("JWT中间件: Token expired\n")
			response.Error(c, http.StatusUnauthorized, "Token expired")
			c.Abort()
			return
		}

		c.Set("user_id", claims.UserID)
		c.Set("username", claims.Username)
		c.Set("role", claims.Role)
		c.Set("device_id", claims.DeviceID)
		c.Set("instance_id", claims.InstanceID)

		fmt.Printf("JWT中间件: 验证成功, user_id=%d, role=%s, device_id=%s, instance_id=%s\n", claims.UserID, claims.Role, claims.DeviceID, claims.InstanceID)
		c.Next()
	}
}

// AdminAuth 管理员权限中间件
func AdminAuth() gin.HandlerFunc {
	return func(c *gin.Context) {
		role, exists := c.Get("role")
		if !exists {
			response.Error(c, http.StatusForbidden, "Access denied")
			c.Abort()
			return
		}

		if role != "admin" {
			response.Error(c, http.StatusForbidden, "Admin access required")
			c.Abort()
			return
		}

		c.Next()
	}
}

// AgentAuth 代理商授权中间件
func AgentAuth() gin.HandlerFunc {
	return func(c *gin.Context) {
		role, exists := c.Get("role")
		if !exists {
			response.Error(c, http.StatusForbidden, "Access denied")
			c.Abort()
			return
		}

		if role != "agent" && role != "admin" {
			response.Error(c, http.StatusForbidden, "Agent access required")
			c.Abort()
			return
		}

		c.Next()
	}
}

// PackageAuth 套餐授权中间件
func PackageAuth() gin.HandlerFunc {
	return func(c *gin.Context) {
		role, _ := c.Get("role")
		if role == "admin" {
			c.Next()
			return
		}

		userID, exists := c.Get("user_id")
		if !exists {
			response.Error(c, 401, "未授权")
			c.Abort()
			return
		}

		var user model.User
		if err := database.DB.First(&user, userID).Error; err != nil {
			response.Error(c, 500, "获取用户信息失败")
			c.Abort()
			return
		}

		if user.CurrentPackageID == nil {
			response.Error(c, 403, "您还没有购买套餐，请先购买套餐后再使用开发者功能")
			c.Abort()
			return
		}

		var userPackage model.UserPackage
		if err := database.DB.Where("user_id = ? AND package_id = ? AND status = ?",
			userID, user.CurrentPackageID, "active").First(&userPackage).Error; err != nil {
			response.Error(c, 403, "套餐授权已失效，请续费或重新购买套餐")
			c.Abort()
			return
		}

		if userPackage.ExpiredAt != nil && userPackage.ExpiredAt.Before(time.Now()) {
			response.Error(c, 403, "套餐已过期，请续费后再使用开发者功能")
			c.Abort()
			return
		}

		c.Set("user_package", &userPackage)
		c.Next()
	}
}

// Logger 日志中间件
func Logger() gin.HandlerFunc {
	return gin.LoggerWithFormatter(func(param gin.LogFormatterParams) string {
		return fmt.Sprintf("%s - [%s] \"%s %s %s %d %s \"%s\" %s\"\n",
			param.ClientIP,
			param.TimeStamp.Format(time.RFC1123),
			param.Method,
			param.Path,
			param.Request.Proto,
			param.StatusCode,
			param.Latency,
			param.Request.UserAgent(),
			param.ErrorMessage,
		)
	})
}

// Recovery 恢复中间件
func Recovery() gin.HandlerFunc {
	return gin.CustomRecovery(func(c *gin.Context, recovered interface{}) {
		response.Error(c, http.StatusInternalServerError, "Internal server error")
	})
}

// Cors 跨域中间件
func Cors() gin.HandlerFunc {
	return func(c *gin.Context) {
		c.Writer.Header().Set("Access-Control-Allow-Origin", "*")
		c.Writer.Header().Set("Access-Control-Allow-Credentials", "false")
		c.Writer.Header().Set("Access-Control-Allow-Headers", "Content-Type, Content-Length, Accept-Encoding, X-CSRF-Token, Authorization, accept, origin, Cache-Control, X-Requested-With")
		c.Writer.Header().Set("Access-Control-Allow-Methods", "POST, OPTIONS, GET, PUT, DELETE, PATCH")
		c.Writer.Header().Set("Access-Control-Max-Age", "86400")

		if c.Request.Method == "OPTIONS" {
			c.AbortWithStatus(http.StatusOK)
			return
		}

		c.Next()
	}
}

// RateLimit 限流中间件
func RateLimit() gin.HandlerFunc {
	return func(c *gin.Context) {
		// 这里可以实现基于Redis的限流逻辑
		// 暂时跳过实现
		c.Next()
	}
}