package handler

import (
    "net/http"
    "time"

    "github.com/gin-gonic/gin"
    "github.com/golang-jwt/jwt/v5"
    "github.com/rs/zerolog/log"
    "golang.org/x/crypto/bcrypt"
)

type RegisterRequest struct {
    Username string `json:"username" binding:"required"`
    Email    string `json:"email" binding:"required,email"`
    Password string `json:"password" binding:"required,min=8"`
    Role     string `json:"role" binding:"required,oneof=admin editor contributor"`
}

type LoginRequest struct {
    Username string `json:"username" binding:"required,min=3,max=32"`
    Password string `json:"password" binding:"required"`
}

type AuthResponse struct {
    Token string `json:"token"`
}

func (h *Handler) Register(c *gin.Context) {
    // 检查是否启用注册功能
    if !h.config.Auth.Registration.Enabled {
        message := h.config.Auth.Registration.Message
        if message == "" {
            message = "Registration is currently disabled"
        }
        c.JSON(http.StatusForbidden, gin.H{
            "error": gin.H{
                "code":    "REGISTRATION_DISABLED",
                "message": message,
            },
        })
        return
    }

    var req RegisterRequest
    if err := c.ShouldBindJSON(&req); err != nil {
        c.JSON(http.StatusBadRequest, gin.H{
            "error": gin.H{
                "code":    "INVALID_REQUEST",
                "message": err.Error(),
            },
        })
        return
    }

    user, err := h.service.CreateUser(c.Request.Context(), req.Username, req.Email, req.Password, req.Role)
    if err != nil {
        log.Error().Err(err).Msg("Failed to create user")
        c.JSON(http.StatusInternalServerError, gin.H{
            "error": gin.H{
                "code":    "CREATE_USER_FAILED",
                "message": "Failed to create user",
            },
        })
        return
    }

    // Get user roles
    roles, err := h.service.GetUserRoles(c.Request.Context(), user.ID)
    if err != nil {
        log.Error().Err(err).Msg("Failed to get user roles")
        c.JSON(http.StatusInternalServerError, gin.H{
            "error": gin.H{
                "code":    "GET_ROLES_FAILED",
                "message": "Failed to get user roles",
            },
        })
        return
    }

    // Extract role names for JWT
    roleNames := make([]string, len(roles))
    for i, r := range roles {
        roleNames[i] = r.Name
    }

    // Generate JWT token
    token := jwt.NewWithClaims(jwt.SigningMethodHS256, jwt.MapClaims{
        "sub":   user.ID,
        "roles": roleNames,
        "exp":   time.Now().Add(24 * time.Hour).Unix(),
    })

    tokenString, err := token.SignedString([]byte(h.cfg.JWT.Secret))
    if err != nil {
        log.Error().Err(err).Msg("Failed to generate token")
        c.JSON(http.StatusInternalServerError, gin.H{
            "error": gin.H{
                "code":    "GENERATE_TOKEN_FAILED",
                "message": "Failed to generate token",
            },
        })
        return
    }

    c.JSON(http.StatusCreated, AuthResponse{Token: tokenString})
}

func (h *Handler) Login(c *gin.Context) {
    var req LoginRequest
    if err := c.ShouldBindJSON(&req); err != nil {
        c.JSON(http.StatusBadRequest, gin.H{
            "error": gin.H{
                "code":    "INVALID_REQUEST",
                "message": err.Error(),
            },
        })
        return
    }

    user, err := h.service.GetUserByUsername(c.Request.Context(), req.Username)
    if err != nil {
        c.JSON(http.StatusUnauthorized, gin.H{
            "error": gin.H{
                "code":    "INVALID_CREDENTIALS",
                "message": "Invalid username or password",
            },
        })
        return
    }

    // 验证密码
    err = bcrypt.CompareHashAndPassword([]byte(user.PasswordHash), []byte(req.Password))
    if err != nil {
        c.JSON(http.StatusUnauthorized, gin.H{
            "error": gin.H{
                "code":    "INVALID_CREDENTIALS",
                "message": "Invalid username or password",
            },
        })
        return
    }

    // Get user roles
    roles, err := h.service.GetUserRoles(c.Request.Context(), user.ID)
    if err != nil {
        log.Error().Err(err).Msg("Failed to get user roles")
        c.JSON(http.StatusInternalServerError, gin.H{
            "error": gin.H{
                "code":    "GET_ROLES_FAILED",
                "message": "Failed to get user roles",
            },
        })
        return
    }

    // Extract role names for JWT
    roleNames := make([]string, len(roles))
    for i, r := range roles {
        roleNames[i] = r.Name
    }

    // Generate JWT token
    token := jwt.NewWithClaims(jwt.SigningMethodHS256, jwt.MapClaims{
        "sub":   user.ID,
        "roles": roleNames,
        "exp":   time.Now().Add(24 * time.Hour).Unix(),
    })

    tokenString, err := token.SignedString([]byte(h.cfg.JWT.Secret))
    if err != nil {
        log.Error().Err(err).Msg("Failed to generate token")
        c.JSON(http.StatusInternalServerError, gin.H{
            "error": gin.H{
                "code":    "GENERATE_TOKEN_FAILED",
                "message": "Failed to generate token",
            },
        })
        return
    }

    c.JSON(http.StatusOK, AuthResponse{Token: tokenString})
}