package admin

import (
	"errors"
	"strconv"
	"strings"
	"time"

	"git.echol.cn/loser/Go-Web-Template/server/global"
	appModel "git.echol.cn/loser/Go-Web-Template/server/model/app"
	"git.echol.cn/loser/Go-Web-Template/server/model/common/response"
	appSvc "git.echol.cn/loser/Go-Web-Template/server/service/app"
	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
)

type AppInviteCodesApi struct{}

type appInviteCodeListItem struct {
	ID              uint                      `json:"id"`
	CreatedByUserID uint                      `json:"createdByUserId"`
	CodeLast4       string                    `json:"codeLast4"`
	Status          appModel.InviteCodeStatus `json:"status"`
	ExpiresAt       *time.Time                `json:"expiresAt,omitempty"`
	UsedByUserID    *uint                     `json:"usedByUserId,omitempty"`
	UsedAt          *time.Time                `json:"usedAt,omitempty"`
	CreatedAt       time.Time                 `json:"createdAt"`
}

type appInviteCodeDetailResponse struct {
	Code    appModel.AppInviteCode `json:"code"`
	Inviter struct {
		ID       uint   `json:"id"`
		Username string `json:"username"`
	} `json:"inviter"`
	Invitee *struct {
		ID       uint   `json:"id"`
		Username string `json:"username"`
	} `json:"invitee,omitempty"`
	Relation *appModel.AppUserInviteRelation `json:"relation,omitempty"`
}

type issueInviteCodeRequest struct {
	UserID      uint `json:"userId" binding:"required"`
	ExpireHours *int `json:"expireHours"`
}

type issueInviteCodeResponse struct {
	Code      string     `json:"code"`
	CodeLast4 string     `json:"codeLast4"`
	ExpiresAt *time.Time `json:"expiresAt,omitempty"`
}

type clearUnusedRequest struct {
	UserID uint   `json:"userId" binding:"required"`
	Scope  string `json:"scope"` // active|all
}

// GetAppInviteCodesList
// @Tags     AppInviteCodesAdmin
// @Summary  后台获取玩家邀请码列表
// @Security ApiKeyAuth
// @Produce  application/json
// @Param    page            query     int     false  "页码" default(1)
// @Param    pageSize        query     int     false  "每页大小" default(10)
// @Param    status          query     string  false  "状态 unused|used|revoked|expired"
// @Param    createdByUserId query     int     false  "邀请人用户ID"
// @Param    usedByUserId    query     int     false  "使用人用户ID"
// @Param    codeLast4       query     string  false  "末4位"
// @Success  200  {object}   response.Response{data=response.PageResult,msg=string}  "获取成功"
// @Router   /admin/app-invite-codes [get]
func (a *AppInviteCodesApi) GetAppInviteCodesList(c *gin.Context) {
	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
	pageSize, _ := strconv.Atoi(c.DefaultQuery("pageSize", "10"))
	if page <= 0 {
		page = 1
	}
	if pageSize <= 0 || pageSize > 200 {
		pageSize = 10
	}

	status := strings.TrimSpace(c.Query("status"))
	createdByUserID, _ := strconv.Atoi(c.Query("createdByUserId"))
	usedByUserID, _ := strconv.Atoi(c.Query("usedByUserId"))
	codeLast4 := strings.TrimSpace(c.Query("codeLast4"))

	db := global.GVA_DB.Model(&appModel.AppInviteCode{})
	if status != "" && status != "expired" {
		db = db.Where("status = ?", status)
	}
	if createdByUserID > 0 {
		db = db.Where("created_by_user_id = ?", createdByUserID)
	}
	if usedByUserID > 0 {
		db = db.Where("used_by_user_id = ?", usedByUserID)
	}
	if codeLast4 != "" {
		db = db.Where("code_last4 = ?", codeLast4)
	}

	// 仅查询“已过期”视图：expires_at < now AND status=unused
	if status == "expired" {
		now := time.Now()
		db = db.Where("status = ?", appModel.InviteCodeStatusUnused).Where("expires_at IS NOT NULL AND expires_at <= ?", now)
	}

	var total int64
	if err := db.Count(&total).Error; err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}

	var list []appModel.AppInviteCode
	if err := db.Order("id desc").Limit(pageSize).Offset((page - 1) * pageSize).Find(&list).Error; err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}

	items := make([]appInviteCodeListItem, 0, len(list))
	for _, rec := range list {
		items = append(items, appInviteCodeListItem{
			ID:              rec.ID,
			CreatedByUserID: rec.CreatedByUserID,
			CodeLast4:       rec.CodeLast4,
			Status:          rec.Status,
			ExpiresAt:       rec.ExpiresAt,
			UsedByUserID:    rec.UsedByUserID,
			UsedAt:          rec.UsedAt,
			CreatedAt:       rec.CreatedAt,
		})
	}

	response.OkWithDetailed(response.PageResult{
		List:     items,
		Total:    total,
		Page:     page,
		PageSize: pageSize,
	}, "获取成功", c)
}

// GetAppInviteCodeById
// @Tags     AppInviteCodesAdmin
// @Summary  后台获取玩家邀请码详情
// @Security ApiKeyAuth
// @Produce  application/json
// @Param    id   path      int  true  "邀请码ID"
// @Success  200  {object}  response.Response{data=appInviteCodeDetailResponse,msg=string}  "获取成功"
// @Router   /admin/app-invite-codes/{id} [get]
func (a *AppInviteCodesApi) GetAppInviteCodeById(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	if id <= 0 {
		response.FailWithMessage("参数错误", c)
		return
	}

	var code appModel.AppInviteCode
	if err := global.GVA_DB.First(&code, id).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			response.FailWithMessage("记录不存在", c)
			return
		}
		response.FailWithMessage(err.Error(), c)
		return
	}

	var inviter appModel.AppUser
	_ = global.GVA_DB.Select("id, username").First(&inviter, code.CreatedByUserID).Error

	var relation appModel.AppUserInviteRelation
	relErr := global.GVA_DB.Where("invite_code_id = ?", code.ID).First(&relation).Error
	var invitee *appModel.AppUser = nil
	if relErr == nil {
		var u appModel.AppUser
		if err := global.GVA_DB.Select("id, username").First(&u, relation.InviteeUserID).Error; err == nil {
			invitee = &u
		}
	}

	payload := appInviteCodeDetailResponse{Code: code}
	payload.Inviter.ID = inviter.ID
	payload.Inviter.Username = inviter.Username
	if invitee != nil {
		payload.Invitee = &struct {
			ID       uint   `json:"id"`
			Username string `json:"username"`
		}{ID: invitee.ID, Username: invitee.Username}
	}
	if relErr == nil {
		payload.Relation = &relation
	}

	response.OkWithData(payload, c)
}

// RevokeAppInviteCode
// @Tags     AppInviteCodesAdmin
// @Summary  作废玩家邀请码
// @Security ApiKeyAuth
// @Produce  application/json
// @Param    id   path      int  true  "邀请码ID"
// @Success  200  {object}  response.Response{msg=string}  "作废成功"
// @Router   /admin/app-invite-codes/{id}/revoke [post]
func (a *AppInviteCodesApi) RevokeAppInviteCode(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	if id <= 0 {
		response.FailWithMessage("参数错误", c)
		return
	}

	var code appModel.AppInviteCode
	if err := global.GVA_DB.First(&code, id).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			response.FailWithMessage("记录不存在", c)
			return
		}
		response.FailWithMessage(err.Error(), c)
		return
	}
	if code.Status == appModel.InviteCodeStatusUsed {
		response.FailWithMessage("已使用的邀请码不可作废", c)
		return
	}
	if code.Status == appModel.InviteCodeStatusRevoked {
		response.OkWithMessage("已作废", c)
		return
	}
	if err := global.GVA_DB.Model(&code).Update("status", appModel.InviteCodeStatusRevoked).Error; err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}
	response.OkWithMessage("作废成功", c)
}

// IssueAppInviteCodeForUser
// @Tags     AppInviteCodesAdmin
// @Summary  后台代用户生成邀请码（返回明文一次性）
// @Security ApiKeyAuth
// @Produce  application/json
// @Param    data  body      issueInviteCodeRequest  true  "用户ID"
// @Success  200   {object}  response.Response{data=issueInviteCodeResponse,msg=string}  "生成成功"
// @Router   /admin/app-invite-codes/issue [post]
func (a *AppInviteCodesApi) IssueAppInviteCodeForUser(c *gin.Context) {
	var req issueInviteCodeRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}

	// 先强制作废该用户所有 active unused
	now := time.Now()
	revokeDB := global.GVA_DB.Model(&appModel.AppInviteCode{}).
		Where("created_by_user_id = ? AND status = ?", req.UserID, appModel.InviteCodeStatusUnused).
		Where(global.GVA_DB.Where("expires_at IS NULL").Or("expires_at > ?", now)).
		Update("status", appModel.InviteCodeStatusRevoked)
	if revokeDB.Error != nil {
		response.FailWithMessage(revokeDB.Error.Error(), c)
		return
	}

	// 复用现有生成逻辑（按系统参数 expireHours），若你传了 expireHours，本期先忽略，后续可扩展为临时覆盖。
	res, err := appSvc.AppInviteCodeServiceApp.Generate(req.UserID)
	if err != nil {
		// 若生成被“已有未使用码”拦住，说明 revoke 未覆盖（例如过期时间为空/逻辑差异），直接返回错误即可。
		response.FailWithMessage(err.Error(), c)
		return
	}
	response.OkWithData(issueInviteCodeResponse{Code: res.Code, CodeLast4: res.CodeLast4, ExpiresAt: res.ExpiresAt}, c)
}

// ClearUnusedInviteCodes
// @Tags     AppInviteCodesAdmin
// @Summary  强制清空用户未使用邀请码（批量作废）
// @Security ApiKeyAuth
// @Produce  application/json
// @Param    data  body      clearUnusedRequest  true  "用户ID"
// @Success  200   {object}  response.Response{msg=string}  "清空成功"
// @Router   /admin/app-invite-codes/clear-unused [post]
func (a *AppInviteCodesApi) ClearUnusedInviteCodes(c *gin.Context) {
	var req clearUnusedRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}
	scope := strings.TrimSpace(req.Scope)
	if scope == "" {
		scope = "active"
	}

	db := global.GVA_DB.Model(&appModel.AppInviteCode{}).
		Where("created_by_user_id = ? AND status = ?", req.UserID, appModel.InviteCodeStatusUnused)
	if scope == "active" {
		now := time.Now()
		db = db.Where(global.GVA_DB.Where("expires_at IS NULL").Or("expires_at > ?", now))
	}

	if err := db.Update("status", appModel.InviteCodeStatusRevoked).Error; err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}
	response.OkWithMessage("清空成功", c)
}