package app

import (
	"fmt"
	"net/http"
	"time"

	"mini-chat/internal/code"
	"mini-chat/internal/pkg/core"
	"mini-chat/internal/pkg/timeutil"
	"mini-chat/internal/pkg/validation"
)

type latestMessageByAppIdRequest struct {
	AppID    string `form:"app_id" binding:"required"` // 小程序ID
	Page     int    `form:"page"`                      // 当前页码，默认1
	PageSize int    `form:"page_size"`                 // 每页返回的数据量，默认20
}

type latestMessageData struct {
	SendTime     string `json:"send_time"`     // 发送时间
	SenderID     string `json:"sender_id"`     // 发送人ID
	SenderName   string `json:"sender_name"`   // 发送人昵称
	SenderAvatar string `json:"sender_avatar"` // 发送人头像
	UnreadCount  int64  `json:"unread_count"`  // 未读数量
}

type latestMessageByAppIdResponse struct {
	Page     int                 `json:"page"`      // 当前页码
	PageSize int                 `json:"page_size"` // 每页返回的数据量
	Total    int64               `json:"total"`     // 符合查询条件的总记录数
	List     []latestMessageData `json:"list"`
}

// LatestMessageByAppId 根据appid获取最新消息记录
// @Summary 根据appid获取最新消息记录
// @Description 管理端根据appid获取最新消息记录，包含已读未读状态，访问时自动标记为已读
// @Tags 管理端.小程序
// @Accept json
// @Produce json
// @Param app_id query string true "小程序ID"
// @Param page query int true "当前页码" default(1)
// @Param page_size query int true "每页返回的数据量，最多 100 条" default(20)
// @Success 200 {object} latestMessageByAppIdResponse
// @Failure 400 {object} code.Failure
// @Router /admin/messages/latest [get]
// @Security LoginVerifyToken
func (h *handler) LatestMessageByAppId() core.HandlerFunc {
	return func(ctx core.Context) {
		req := new(latestMessageByAppIdRequest)
		res := new(latestMessageByAppIdResponse)
		if err := ctx.ShouldBindForm(req); err != nil {
			ctx.AbortWithError(core.Error(
				http.StatusBadRequest,
				code.ParamBindError,
				validation.Error(err)),
			)
			return
		}

		if req.Page == 0 {
			req.Page = 1
		}

		if req.PageSize == 0 {
			req.PageSize = 20
		}

		if req.PageSize > 100 {
			ctx.AbortWithError(core.Error(
				http.StatusBadRequest,
				code.ListMessageError,
				fmt.Sprintf("%s: 一次最多只能查询 100 条", code.Text(code.ListMessageError)),
			))
			return
		}

		type unreadMessageResult struct {
			SenderID    string    `json:"sender_id"`
			SenderName  string    `json:"sender_name"`
			SendTime    time.Time `json:"send_time"`
			AvatarURL   string    `json:"avatar_url"`
			UnreadCount int64     `json:"unread_count"`
		}

		var results []unreadMessageResult
		var total int64

		countErr := h.db.GetDbR().Table("app_message_log m").
			Select("m.send_time, m.sender_id, m.sender_name, u.user_avatar as avatar_url, COUNT(*) as unread_count").
			Joins("LEFT JOIN app_user u ON m.sender_id = u.user_id").
			Where("m.app_id = ? AND m.sender_id != ? AND m.is_read = 1", req.AppID, "888888").
			Group("m.sender_id").
			Count(&total).
			Error
		if countErr != nil {
			ctx.AbortWithError(core.Error(
				http.StatusBadRequest,
				code.ListMessageError,
				fmt.Sprintf("%s：%s", code.Text(code.ListMessageError), countErr.Error())),
			)
			return
		}

		resultErr := h.db.GetDbR().Table("app_message_log m").
			Select("max(m.send_time) as send_time, m.sender_id, max(m.sender_name) as sender_name, max(u.user_avatar) as avatar_url, COUNT(*) as unread_count").
			Joins("LEFT JOIN app_user u ON m.sender_id = u.user_id").
			Where("m.app_id = ? AND m.sender_id != ? AND m.is_read = 1", req.AppID, "888888").
			Group("m.sender_id").
			Order("unread_count DESC").
			Offset((req.Page - 1) * req.PageSize).
			Limit(req.PageSize).
			Find(&results).
			Error
		if resultErr != nil {
			ctx.AbortWithError(core.Error(
				http.StatusBadRequest,
				code.ListMessageError,
				fmt.Sprintf("%s：%s", code.Text(code.ListMessageError), resultErr.Error())),
			)
			return
		}

		// 自动标记该appid下的所有消息为已读（管理端访问时）
		_, err := h.writeDB.AppMessageLog.WithContext(ctx.RequestContext()).
			Where(h.writeDB.AppMessageLog.AppID.Eq(req.AppID)).
			Where(h.writeDB.AppMessageLog.IsRead.Eq(0)).
			Update(h.writeDB.AppMessageLog.IsRead, 1)
		if err != nil {
			// 记录错误但不影响查询结果
			// TODO: 可以添加日志记录
		}

		res.Page = req.Page
		res.PageSize = req.PageSize
		res.Total = total
		res.List = make([]latestMessageData, len(results))

		for k, v := range results {
			res.List[k] = latestMessageData{
				SendTime:     timeutil.FriendlyTime(v.SendTime),
				SenderID:     v.SenderID,
				SenderName:   v.SenderName,
				SenderAvatar: v.AvatarURL,
				UnreadCount:  v.UnreadCount,
			}
		}

		ctx.Payload(res)
	}
}