package user

import (
	"net/http"

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

type Handler struct {
	svc *Service
}

func NewHandler(svc *Service) *Handler {
	return &Handler{svc: svc}
}

type registerReq struct {
	Username string `json:"username"`
	Password string `json:"password"`
}

type loginReq struct {
	Username string `json:"username"`
	Password string `json:"password"`
}

func (h *Handler) Register(c *gin.Context) {
	var req registerReq
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "invalid request"})
		return
	}

	if err := h.svc.Register(c.Request.Context(), req.Username, req.Password); err != nil {
		if err == ErrUserAlreadyExists {
			c.JSON(http.StatusConflict, gin.H{"code": 409, "message": "user already exists"})
			return
		}
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{"code": 0, "message": "register success"})
}

func (h *Handler) Login(c *gin.Context) {
	var req loginReq
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"code": 400, "message": "invalid request"})
		return
	}

	token, err := h.svc.Login(c.Request.Context(), req.Username, req.Password)
	if err != nil {
		// login 统一返回 401，避免泄露用户名是否存在
		c.JSON(http.StatusUnauthorized, gin.H{"code": 401, "message": "invalid credentials"})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"code":    0,
		"message": "login success",
		"data": gin.H{
			"token":      token,
			"token_type": "Bearer",
		},
	})
}

// Me 当前登录用户信息（需要 JWT middleware）。
func (h *Handler) Me(c *gin.Context) {
	username, ok := c.Get("username")
	if !ok || username == "" {
		c.JSON(http.StatusUnauthorized, gin.H{"code": 401, "message": "unauthorized"})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"code":    0,
		"message": "ok",
		"data": gin.H{
			"username": username,
		},
	})
}