package middleware

import (
    "net/http"
    "strings"

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

// AuthMiddleware creates a middleware for JWT authentication
func AuthMiddleware(jwtSecret string) 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
        }

        token, err := jwt.Parse(parts[1], func(token *jwt.Token) (interface{}, error) {
            if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
                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 {
            c.Set("user_id", claims["sub"])
            c.Set("user_role", claims["role"])
            c.Next()
        } 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) {
        userRole, exists := c.Get("user_role")
        if !exists {
            c.JSON(http.StatusUnauthorized, gin.H{"error": "User role not found"})
            c.Abort()
            return
        }

        roleStr, ok := userRole.(string)
        if !ok {
            c.JSON(http.StatusInternalServerError, gin.H{"error": "Invalid user role type"})
            c.Abort()
            return
        }

        for _, role := range roles {
            if role == roleStr {
                c.Next()
                return
            }
        }

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