package middleware

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

    "github.com/gin-gonic/gin"
    "github.com/golang-jwt/jwt/v5"
    "github.com/rs/zerolog/log"
    "tss-rocks-be/internal/service"
)

// AuthMiddleware creates a middleware for JWT authentication
func AuthMiddleware(jwtSecret string, tokenBlacklist *service.TokenBlacklist) gin.HandlerFunc {
    return func(c *gin.Context) {
        authHeader := c.GetHeader("Authorization")
        if authHeader == "" {
            c.JSON(http.StatusUnauthorized, gin.H{"error": "Authorization header is required"})
            c.Abort()
            return
        }

        parts := strings.Split(authHeader, " ")
        if len(parts) != 2 || parts[0] != "Bearer" {
            c.JSON(http.StatusUnauthorized, gin.H{"error": "Authorization header format must be Bearer {token}"})
            c.Abort()
            return
        }

        tokenStr := parts[1]

        // 检查 token 是否在黑名单中
        if tokenBlacklist.IsBlacklisted(tokenStr) {
            c.JSON(http.StatusUnauthorized, gin.H{"error": "Token has been revoked"})
            c.Abort()
            return
        }

        token, err := jwt.Parse(tokenStr, func(token *jwt.Token) (interface{}, error) {
            // 添加调试输出
            log.Debug().Str("token", tokenStr).Msg("Parsing token")
            if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
                log.Error().Str("method", token.Method.Alg()).Msg("Invalid signing method")
                return nil, jwt.ErrSignatureInvalid
            }
            return []byte(jwtSecret), nil
        })

        if err != nil {
            log.Error().Err(err).Msg("Failed to parse token")
            c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid token"})
            c.Abort()
            return
        }

        if claims, ok := token.Claims.(jwt.MapClaims); ok && token.Valid {
            // 添加调试信息
            log.Debug().Interface("claims", claims).Msg("Token claims")
            
            // 获取用户ID
            sub, exists := claims["sub"]
            if !exists {
                log.Error().Msg("Token does not contain sub claim")
                c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid token format"})
                c.Abort()
                return
            }

            // 打印类型信息
            log.Debug().
                Str("type", fmt.Sprintf("%T", sub)).
                Interface("value", sub).
                Msg("User ID from token")

            // 将用户 ID 转换为字符串
            var userIDStr string
            switch v := sub.(type) {
            case string:
                userIDStr = v
            case float64:
                userIDStr = strconv.FormatFloat(v, 'f', 0, 64)
            case json.Number:
                userIDStr = v.String()
            default:
                userIDStr = fmt.Sprintf("%v", v)
            }

            // 验证用户 ID 是否为有效的数字字符串
            _, err := strconv.Atoi(userIDStr)
            if err != nil {
                log.Error().
                    Err(err).
                    Str("user_id", userIDStr).
                    Msg("Invalid user ID format")
                c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid user ID format"})
                c.Abort()
                return
            }

            // 获取用户角色
            roles, exists := claims["roles"]
            if !exists {
                log.Error().Msg("Token does not contain roles claim")
                c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid token format: missing roles"})
                c.Abort()
                return
            }

            // 将角色转换为字符串数组
            var roleNames []string
            if rolesArray, ok := roles.([]interface{}); ok {
                for _, r := range rolesArray {
                    if roleStr, ok := r.(string); ok {
                        roleNames = append(roleNames, roleStr)
                    }
                }
            }

            // 设置上下文
            c.Set("user_id", userIDStr)
            c.Set("user_roles", roleNames)  // 存储角色数组
            c.Next()
            return
        } else {
            c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid token"})
            c.Abort()
            return
        }
    }
}

// RoleMiddleware creates a middleware for role-based authorization
func RoleMiddleware(roles ...string) gin.HandlerFunc {
    return func(c *gin.Context) {
        userRoles, exists := c.Get("user_roles")
        if !exists {
            log.Error().Msg("User roles not found in context")
            c.JSON(http.StatusUnauthorized, gin.H{"error": "User roles not found"})
            c.Abort()
            return
        }

        roleNames, ok := userRoles.([]string)
        if !ok {
            log.Error().Msg("Invalid user roles type")
            c.JSON(http.StatusInternalServerError, gin.H{"error": "Invalid user roles type"})
            c.Abort()
            return
        }

        // 检查用户是否拥有任一所需角色
        for _, requiredRole := range roles {
            for _, userRole := range roleNames {
                if requiredRole == userRole {
                    c.Next()
                    return
                }
            }
        }

        log.Warn().
            Strs("required_roles", roles).
            Strs("user_roles", roleNames).
            Msg("Insufficient permissions")

        c.JSON(http.StatusForbidden, gin.H{"error": "Insufficient permissions"})
        c.Abort()
    }
}