package handler

import (
	"errors"
	"io"
	"net/http"
	"time"

	"github.com/gin-gonic/gin"

	"wx_service/internal/middleware"
	"wx_service/internal/model"
	smokeservice "wx_service/internal/smoke/service"
)

type unlockAIAdviceRequest struct {
	Date        string `json:"date"`
	AdWatchedAt string `json:"ad_watched_at"`
}

func (h *SmokeHandler) GetAIAdvice(c *gin.Context) {
	user, ok := middleware.CurrentUser(c)
	if !ok {
		c.JSON(http.StatusUnauthorized, model.Error(http.StatusUnauthorized, "未登录或登录已过期"))
		return
	}

	dateStr := c.Query("date")
	adviceDate := yesterdayDate()
	if dateStr != "" {
		parsed, err := time.ParseInLocation(dateLayout, dateStr, time.Local)
		if err != nil {
			c.JSON(http.StatusBadRequest, model.Error(http.StatusBadRequest, "date 格式错误，应为 YYYY-MM-DD"))
			return
		}
		adviceDate = parsed
	}

	record, err := h.smokeAIAdviceService.GetOrGenerate(c.Request.Context(), user, adviceDate, smokeservice.DefaultAdvicePromptVersion)
	if err != nil {
		switch {
		case errors.Is(err, smokeservice.ErrAIAdviceLocked):
			c.JSON(http.StatusForbidden, model.Error(http.StatusForbidden, "需要会员或观看广告解锁后才可生成建议"))
			return
		case errors.Is(err, smokeservice.ErrAIServiceDisabled):
			c.JSON(http.StatusServiceUnavailable, model.Error(http.StatusServiceUnavailable, "AI 服务暂不可用，请联系管理员"))
			return
		case errors.Is(err, smokeservice.ErrNoSmokeLogs):
			c.JSON(http.StatusBadRequest, model.Error(http.StatusBadRequest, "该日期没有抽烟记录，无法生成建议"))
			return
		default:
			c.JSON(http.StatusInternalServerError, model.Error(http.StatusInternalServerError, "生成建议失败，请稍后重试"))
			return
		}
	}

	c.JSON(http.StatusOK, model.Success(gin.H{
		"date":   record.AdviceDate.Format(dateLayout),
		"advice": record.Advice,
	}))
}

func (h *SmokeHandler) UnlockAIAdvice(c *gin.Context) {
	user, ok := middleware.CurrentUser(c)
	if !ok {
		c.JSON(http.StatusUnauthorized, model.Error(http.StatusUnauthorized, "未登录或登录已过期"))
		return
	}

	var req unlockAIAdviceRequest
	if err := c.ShouldBindJSON(&req); err != nil && !errors.Is(err, io.EOF) {
		c.JSON(http.StatusBadRequest, model.Error(http.StatusBadRequest, "请求参数错误"))
		return
	}

	unlockDate := yesterdayDate()
	if req.Date != "" {
		parsed, err := time.ParseInLocation(dateLayout, req.Date, time.Local)
		if err != nil {
			c.JSON(http.StatusBadRequest, model.Error(http.StatusBadRequest, "date 格式错误，应为 YYYY-MM-DD"))
			return
		}
		unlockDate = parsed
	}

	if err := h.smokeAIAdviceService.Unlock(c.Request.Context(), user, unlockDate); err != nil {
		c.JSON(http.StatusInternalServerError, model.Error(http.StatusInternalServerError, "解锁失败，请稍后重试"))
		return
	}

	c.JSON(http.StatusOK, model.Success(gin.H{
		"unlocked": true,
		"date":     unlockDate.Format(dateLayout),
	}))
}

func yesterdayDate() time.Time {
	now := time.Now().In(time.Local)
	y := now.AddDate(0, 0, -1)
	return time.Date(y.Year(), y.Month(), y.Day(), 0, 0, 0, 0, time.Local)
}