package handler

import (
	"crypto/rand"
	"encoding/hex"
	"kenaito-conf/server/internal/dao"
	"kenaito-conf/server/internal/middleware"
	"kenaito-conf/server/internal/model"
	"net/http"
	"strconv"
	"strings"
	"time"

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

type AppHandler struct{}

func NewAppHandler() *AppHandler {
	return &AppHandler{}
}

type AppListRequest struct {
	PageNo   int    `form:"pageNo" binding:"required"`
	PageSize int    `form:"pageSize" binding:"required"`
	AppType  string `form:"appType"`
	Name     string `form:"name"`
	Code     string `form:"code"`
	GroupId  string `form:"groupId"`
}

func (h *AppHandler) List(c *gin.Context) {
	var req AppListRequest
	if err := c.ShouldBindQuery(&req); err != nil {
		c.JSON(http.StatusBadRequest, model.WrapperResponse{Code: 400, Msg: "参数错误"})
		return
	}

	userInfo := middleware.GetUserInfo(c)
	query := dao.Engine.Where("enabled = 1")

	if !userInfo.IsSuperAdmin() {
		userId, _ := strconv.Atoi(userInfo.Id)
		userIdStr := strconv.Itoa(userId)

		if userInfo.IsGroupAdmin() && userInfo.GroupId != nil {
			// 组管理员：本组应用 + 自己是负责人的应用
			query = query.And("(group_id = ? OR FIND_IN_SET('" + userIdStr + "', owner_ids) > 0 OR id IN (SELECT app_id FROM user_permission WHERE user_id = ?))", *userInfo.GroupId, userId)
		} else {
			// 普通用户：自己是负责人的应用 + 被授权的应用
			query = query.And("(FIND_IN_SET('" + userIdStr + "', owner_ids) > 0 OR id IN (SELECT app_id FROM user_permission WHERE user_id = ?))", userId)
		}
	}

	var apps []model.Application
	whereClause := "enabled = 1"
	if !userInfo.IsSuperAdmin() {
		userId, _ := strconv.Atoi(userInfo.Id)
		userIdStr := strconv.Itoa(userId)
		
		if userInfo.IsGroupAdmin() && userInfo.GroupId != nil {
			// 组管理员：本组应用 + 自己是负责人的应用
			whereClause += " AND (group_id = " + strconv.Itoa(*userInfo.GroupId) + " OR FIND_IN_SET('" + userIdStr + "', owner_ids) > 0 OR id IN (SELECT app_id FROM user_permission WHERE user_id = " + strconv.Itoa(userId) + "))"
		} else {
			// 普通用户：自己是负责人的应用 + 被授权的应用
			whereClause += " AND (FIND_IN_SET('" + userIdStr + "', owner_ids) > 0 OR id IN (SELECT app_id FROM user_permission WHERE user_id = " + strconv.Itoa(userId) + "))"
		}
	}
	if req.AppType != "" {
		whereClause += " AND service_id = '" + req.AppType + "'"
	}
	if req.Name != "" {
		whereClause += " AND name LIKE '%" + req.Name + "%'"
	}
	if req.Code != "" {
		whereClause += " AND code LIKE '%" + req.Code + "%'"
	}
	if req.GroupId != "" {
		whereClause += " AND group_id = " + req.GroupId
	}
	
	total, _ := dao.Engine.Where(whereClause).Count(&model.Application{})
	dao.Engine.Where(whereClause).Limit(req.PageSize, (req.PageNo-1)*req.PageSize).Find(&apps)

	// load group names - batch query to avoid N+1
	groupIds := make(map[int]bool)
	for _, app := range apps {
		if app.GroupId != nil {
			groupIds[*app.GroupId] = true
		}
	}
	groupMap := make(map[int]string)
	if len(groupIds) > 0 {
		ids := make([]int, 0, len(groupIds))
		for gid := range groupIds {
			ids = append(ids, gid)
		}
		var groups []model.BusinessGroup
		dao.Engine.In("id", ids).Find(&groups)
		for _, g := range groups {
			groupMap[g.Id] = g.Name
		}
	}
	for i := range apps {
		if apps[i].GroupId != nil {
			apps[i].GroupName = groupMap[*apps[i].GroupId]
		}
	}

	c.JSON(http.StatusOK, model.PageResult{PageNo: req.PageNo, PageSize: req.PageSize, Total: total, Data: apps})
}

func (h *AppHandler) GetById(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	var app model.Application
	has, _ := dao.Engine.ID(id).Get(&app)
	if !has {
		c.JSON(http.StatusOK, model.WrapperResponse{Code: 404, Msg: "应用不存在"})
		return
	}
	c.JSON(http.StatusOK, model.WrapperResponse{Code: 0, Data: app})
}

type AddAppRequest struct {
	Id        int     `json:"id"`
	GroupId   *int    `json:"groupId"`
	Name      string  `json:"name" binding:"required"`
	Code      string  `json:"code" binding:"required"`
	ServiceId string  `json:"serviceId"`
	OwnerIds  []int   `json:"ownerIds"`
	Remarks   string  `json:"remarks"`
}

func (h *AppHandler) Add(c *gin.Context) {
	var req AddAppRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, model.WrapperResponse{Code: 400, Msg: "参数错误"})
		return
	}

	userInfo := middleware.GetUserInfo(c)

	// check if code exists
	var existing model.Application
	if has, _ := dao.Engine.Where("code = ?", req.Code).Get(&existing); has {
		c.JSON(http.StatusOK, model.WrapperResponse{Code: 1002, Msg: "应用已存在"})
		return
	}

	// 处理负责人：如果未指定，默认为当前用户
	ownerIds := req.OwnerIds
	if len(ownerIds) == 0 {
		uid, _ := strconv.Atoi(userInfo.Id)
		ownerIds = []int{uid}
	}

	// 验证所有用户ID都存在
	var users []model.User
	if err := dao.Engine.In("id", ownerIds).Find(&users); err != nil || len(users) != len(ownerIds) {
		c.JSON(http.StatusOK, model.WrapperResponse{Code: 400, Msg: "部分负责人不存在"})
		return
	}

	// 构建逗号分隔的用户名和ID字符串
	ownerNames := make([]string, 0, len(users))
	ownerIdStrs := make([]string, 0, len(users))
	for _, u := range users {
		ownerNames = append(ownerNames, u.Name)
		ownerIdStrs = append(ownerIdStrs, strconv.Itoa(u.Id))
	}

	app := model.Application{
		GroupId:    req.GroupId,
		Name:       req.Name,
		Code:       req.Code,
		ServiceId:  req.ServiceId,
		OwnerIds:   strings.Join(ownerIdStrs, ","),
		OwnerNames: strings.Join(ownerNames, ","),
		Remarks:    req.Remarks,
		Enabled:    true,
		CreatedAt:  func() *time.Time { t := time.Now(); return &t }(),
		CreatedBy:  userInfo.Name,
	}

	dao.Engine.Insert(&app)

	c.JSON(http.StatusOK, model.WrapperResponse{Code: 0, Data: true})
}

func (h *AppHandler) Update(c *gin.Context) {
	var req AddAppRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, model.WrapperResponse{Code: 400, Msg: "参数错误"})
		return
	}

	if req.Id == 0 {
		c.JSON(http.StatusOK, model.WrapperResponse{Code: 400, Msg: "id参数缺失"})
		return
	}

	var app model.Application
	has, _ := dao.Engine.ID(req.Id).Get(&app)
	if !has {
		c.JSON(http.StatusOK, model.WrapperResponse{Code: 404, Msg: "应用不存在"})
		return
	}

	userInfo := middleware.GetUserInfo(c)

	app.Name = req.Name
	app.ServiceId = req.ServiceId
	app.Remarks = req.Remarks

	// 更新负责人
	if len(req.OwnerIds) > 0 {
		// 验证所有用户ID都存在
		var users []model.User
		if err := dao.Engine.In("id", req.OwnerIds).Find(&users); err != nil || len(users) != len(req.OwnerIds) {
			c.JSON(http.StatusOK, model.WrapperResponse{Code: 400, Msg: "部分负责人不存在"})
			return
		}

		// 构建逗号分隔的用户名和ID字符串
		ownerNames := make([]string, 0, len(users))
		ownerIdStrs := make([]string, 0, len(users))
		for _, u := range users {
			ownerNames = append(ownerNames, u.Name)
			ownerIdStrs = append(ownerIdStrs, strconv.Itoa(u.Id))
		}
		app.OwnerIds = strings.Join(ownerIdStrs, ",")
		app.OwnerNames = strings.Join(ownerNames, ",")
	}

	app.UpdatedBy = userInfo.Name
	now := time.Now()
	app.UpdatedAt = &now

	dao.Engine.ID(app.Id).Cols("name", "service_id", "remarks", "owner_ids", "owner_names", "updated_by", "updated_at").Update(&app)

	c.JSON(http.StatusOK, model.WrapperResponse{Code: 0, Data: true})
}

func (h *AppHandler) Delete(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	userInfo := middleware.GetUserInfo(c)

	if !userInfo.IsSuperAdmin() {
		c.JSON(http.StatusForbidden, model.WrapperResponse{Code: 403, Msg: "超级管理员才能删除"})
		return
	}

	var app model.Application
	has, _ := dao.Engine.ID(id).Get(&app)
	if !has {
		c.JSON(http.StatusOK, model.WrapperResponse{Code: 404, Msg: "应用不存在"})
		return
	}

	app.Enabled = false
	app.UpdatedBy = userInfo.Name
	now := time.Now()
	app.UpdatedAt = &now
	dao.Engine.ID(app.Id).Cols("enabled", "updated_by", "updated_at").Update(&app)

	// soft delete related configs
	dao.Engine.Where("app_id = ?", id).Cols("enabled").Update(&model.AppConfig{Enabled: false})

	c.JSON(http.StatusOK, model.WrapperResponse{Code: 0})
}

func (h *AppHandler) Switch(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	userInfo := middleware.GetUserInfo(c)

	var app model.Application
	has, _ := dao.Engine.ID(id).Get(&app)
	if !has {
		c.JSON(http.StatusOK, model.WrapperResponse{Code: 404, Msg: "应用不存在"})
		return
	}

	app.Enabled = !app.Enabled
	app.UpdatedBy = userInfo.Name
	now := time.Now()
	app.UpdatedAt = &now
	dao.Engine.ID(app.Id).Cols("enabled", "updated_by", "updated_at").Update(&app)

	c.JSON(http.StatusOK, model.WrapperResponse{Code: 0, Data: true})
}

func (h *AppHandler) Options(c *gin.Context) {
	userInfo := middleware.GetUserInfo(c)
	query := dao.Engine.Where("enabled = 1")

	if !userInfo.IsSuperAdmin() {
		if userInfo.IsGroupAdmin() && userInfo.GroupId != nil {
			query = query.And("group_id = ?", *userInfo.GroupId)
		} else {
			userId, _ := strconv.Atoi(userInfo.Id)
			userIdStr := strconv.Itoa(userId)
			query = query.And("FIND_IN_SET(?, owner_ids) > 0", userIdStr)
		}
	}

	var apps []model.Application
	query.Find(&apps)

	options := make([]model.SelectOption, 0)
	for _, app := range apps {
		options = append(options, model.SelectOption{Value: strconv.Itoa(app.Id), Label: app.Name})
	}

	c.JSON(http.StatusOK, model.WrapperResponse{Code: 0, Data: options})
}

func (h *AppHandler) GenerateToken(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	userInfo := middleware.GetUserInfo(c)

	var app model.Application
	has, _ := dao.Engine.ID(id).Get(&app)
	if !has {
		c.JSON(http.StatusOK, model.WrapperResponse{Code: 404, Msg: "应用不存在"})
		return
	}

	bytes := make([]byte, 32)
	if _, err := rand.Read(bytes); err != nil {
		c.JSON(http.StatusOK, model.WrapperResponse{Code: 500, Msg: "生成 Token 失败"})
		return
	}
	token := hex.EncodeToString(bytes)

	app.Token = token
	app.UpdatedBy = userInfo.Name
	now := time.Now()
	app.UpdatedAt = &now
	dao.Engine.ID(app.Id).Cols("token", "updated_by", "updated_at").Update(&app)

	c.JSON(http.StatusOK, model.WrapperResponse{Code: 0, Data: token})
}

func (h *AppHandler) DeleteToken(c *gin.Context) {
	id, _ := strconv.Atoi(c.Param("id"))
	userInfo := middleware.GetUserInfo(c)

	var app model.Application
	has, _ := dao.Engine.ID(id).Get(&app)
	if !has {
		c.JSON(http.StatusOK, model.WrapperResponse{Code: 404, Msg: "应用不存在"})
		return
	}

	app.Token = ""
	app.UpdatedBy = userInfo.Name
	now := time.Now()
	app.UpdatedAt = &now
	dao.Engine.ID(app.Id).Cols("token", "updated_by", "updated_at").Update(&app)

	c.JSON(http.StatusOK, model.WrapperResponse{Code: 0, Data: true})
}