package handler

import (
	"net/http"

	"affiliate_dash/internal/pkg/response"
	"affiliate_dash/internal/service"

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

// DCAuthHandler 暴露 DCAuth 2.0.0 协议端点。
type DCAuthHandler struct {
	svc *service.DCAuthService
}

func NewDCAuthHandler(svc *service.DCAuthService) *DCAuthHandler {
	return &DCAuthHandler{svc: svc}
}

// Authorize 接收 DCAuth 客户端签名并推进 challenge 到 authorized。
func (h *DCAuthHandler) Authorize(c *gin.Context) {
	if h == nil || h.svc == nil {
		writeDCAuthError(c, newDCAuthUnavailable())
		return
	}
	var req service.DCAuthorizeRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		writeDCAuthError(c, &service.AuthError{Status: http.StatusBadRequest, Code: "payload_invalid", Message: "设备认证参数无效"})
		return
	}
	if err := h.svc.Authorize(req); err != nil {
		writeDCAuthError(c, err)
		return
	}
	response.OK(c, gin.H{"status": "authorized"})
}

// Status 轮询 challenge 状态；authorized 时签发一次性 deviceTicket。
func (h *DCAuthHandler) Status(c *gin.Context) {
	if h == nil || h.svc == nil {
		writeDCAuthError(c, newDCAuthUnavailable())
		return
	}
	pollToken := c.GetHeader("X-Poll-Token")
	if pollToken == "" {
		pollToken = c.Query("pollToken")
	}
	status, err := h.svc.ChallengeStatus(c.Param("challengeId"), pollToken)
	if err != nil {
		writeDCAuthError(c, err)
		return
	}
	response.OK(c, status)
}

func newDCAuthUnavailable() *service.AuthError {
	return &service.AuthError{Status: http.StatusServiceUnavailable, Code: "device_auth_unavailable", Message: "设备认证服务未配置"}
}

// writeDCAuthError 使用协议约定的字符串 error code，便于 DCAuth 客户端识别。
func writeDCAuthError(c *gin.Context, err error) {
	if authErr, ok := service.AsAuthError(err); ok {
		c.JSON(authErr.Status, gin.H{"code": authErr.Code, "message": authErr.Message})
		return
	}
	c.JSON(http.StatusInternalServerError, gin.H{"code": "internal_error", "message": "设备认证服务异常"})
}