package controllers

import (
	"encoding/json"
	"strconv"
	"strings"
	"time"

	"server/models"
	"server/pkg/identity"
	"server/pkg/jwtutil"

	"github.com/beego/beego/v2/client/orm"
	beego "github.com/beego/beego/v2/server/web"
)

// BackendOaSchedulingController OA 工作排班（班次 / 排班方案 / 排班看板 / 临时调配）。
//
// 排班的作用范围直接复用租户的组织架构（yz_backend_organization）：
// 公司、部门、小组是同一棵树上的不同层级，选中某个节点并勾选“含下级”
// 即可把排班下发给该节点下的全部员工；也可以跳过组织，直接挑选
// 一个或多个员工做临时安排。所有数据按 JWT 中的 tid 做租户隔离。
type BackendOaSchedulingController struct {
	beego.Controller
}

// ---------------------------------------------------------------------------
// 认证与响应
// ---------------------------------------------------------------------------

func (c *BackendOaSchedulingController) scClaims() (*jwtutil.Claims, bool) {
	claims, err := identity.Claims(c.Ctx.Request.Header.Get("Authorization"), identity.EndBackend)
	if err != nil || claims.TenantId <= 0 {
		return nil, false
	}
	return claims, true
}

// scOperator 返回当前操作人信息：tid、uid、用户名。
func (c *BackendOaSchedulingController) scOperator() (uint64, uint64, string, bool) {
	claims, ok := c.scClaims()
	if !ok {
		c.scFail(401, 401, "未登录或登录已过期")
		return 0, 0, "", false
	}
	return uint64(claims.TenantId), uint64(claims.UserID), claims.Username, true
}

func (c *BackendOaSchedulingController) scOK(data interface{}) {
	c.Data["json"] = map[string]interface{}{"code": 200, "msg": "success", "data": data}
	_ = c.ServeJSON()
}

func (c *BackendOaSchedulingController) scFail(httpStatus, bizCode int, msg string) {
	if httpStatus > 0 {
		c.Ctx.Output.SetStatus(httpStatus)
	}
	c.Data["json"] = map[string]interface{}{"code": bizCode, "msg": msg}
	_ = c.ServeJSON()
}

func (c *BackendOaSchedulingController) scBody() map[string]interface{} {
	body := map[string]interface{}{}
	if len(c.Ctx.Input.RequestBody) == 0 {
		return body
	}
	_ = json.Unmarshal(c.Ctx.Input.RequestBody, &body)
	return body
}

func (c *BackendOaSchedulingController) scPathID(param string) (uint64, bool) {
	id, err := strconv.ParseUint(strings.TrimSpace(c.Ctx.Input.Param(param)), 10, 64)
	return id, err == nil && id > 0
}

// ---------------------------------------------------------------------------
// 参数解析辅助
// ---------------------------------------------------------------------------

func scStringValue(body map[string]interface{}, keys ...string) string {
	for _, key := range keys {
		raw, ok := body[key]
		if !ok || raw == nil {
			continue
		}
		switch value := raw.(type) {
		case string:
			return strings.TrimSpace(value)
		case float64:
			return strconv.FormatFloat(value, 'f', -1, 64)
		case bool:
			return strconv.FormatBool(value)
		}
	}
	return ""
}

func scIntValue(body map[string]interface{}, keys ...string) (int, bool) {
	raw := scStringValue(body, keys...)
	if raw == "" {
		return 0, false
	}
	value, err := strconv.Atoi(raw)
	return value, err == nil
}

func scUintValue(body map[string]interface{}, keys ...string) uint64 {
	raw := scStringValue(body, keys...)
	if raw == "" {
		return 0
	}
	value, err := strconv.ParseUint(raw, 10, 64)
	if err != nil {
		return 0
	}
	return value
}

// scUintSlice 解析 [] 形式的 ID 列表，兼容数字与字符串两种元素。
func scUintSlice(body map[string]interface{}, key string) []uint64 {
	raw, ok := body[key]
	if !ok || raw == nil {
		return nil
	}
	list, ok := raw.([]interface{})
	if !ok {
		return nil
	}
	ids := make([]uint64, 0, len(list))
	seen := map[uint64]bool{}
	for _, item := range list {
		var value uint64
		switch v := item.(type) {
		case float64:
			value = uint64(v)
		case string:
			value, _ = strconv.ParseUint(strings.TrimSpace(v), 10, 64)
		}
		if value > 0 && !seen[value] {
			seen[value] = true
			ids = append(ids, value)
		}
	}
	return ids
}

func scBoolValue(body map[string]interface{}, keys ...string) bool {
	for _, key := range keys {
		raw, ok := body[key]
		if !ok || raw == nil {
			continue
		}
		switch value := raw.(type) {
		case bool:
			return value
		case float64:
			return value != 0
		case string:
			return value == "1" || strings.EqualFold(value, "true")
		}
	}
	return false
}

// scWeekdaySet 解析星期筛选，1=周一 ... 7=周日。
// 支持 [1,3,5] 数组与 "1,3,5" 字符串；空值表示每天。
func scWeekdaySet(body map[string]interface{}) map[int]bool {
	result := map[int]bool{}
	raw, ok := body["weekdays"]
	if !ok || raw == nil {
		return result
	}
	add := func(value int) {
		if value >= 1 && value <= 7 {
			result[value] = true
		}
	}
	switch list := raw.(type) {
	case []interface{}:
		for _, item := range list {
			switch v := item.(type) {
			case float64:
				add(int(v))
			case string:
				n, _ := strconv.Atoi(strings.TrimSpace(v))
				add(n)
			}
		}
	case string:
		for _, part := range strings.Split(list, ",") {
			n, _ := strconv.Atoi(strings.TrimSpace(part))
			add(n)
		}
	}
	return result
}

// scParseDate 解析 "YYYY-MM-DD" 并返回时间对象。
func scParseDate(value string) (time.Time, bool) {
	if !isValidOaDate(value) {
		return time.Time{}, false
	}
	parsed, err := time.ParseInLocation("2006-01-02", value, time.Local)
	if err != nil {
		return time.Time{}, false
	}
	return parsed, true
}

// scDateSpan 展开 [start, end] 之间的全部日期字符串；区间上限 92 天，
// 避免一次请求把看板拖垮。
func scDateSpan(start, end string) ([]string, string) {
	startDate, ok := scParseDate(start)
	if !ok {
		return nil, "开始日期格式错误"
	}
	endDate, ok := scParseDate(end)
	if !ok {
		return nil, "结束日期格式错误"
	}
	if endDate.Before(startDate) {
		return nil, "结束日期不能早于开始日期"
	}
	if endDate.Sub(startDate) > 92*24*time.Hour {
		return nil, "日期区间不能超过 92 天"
	}
	dates := make([]string, 0, 32)
	for cursor := startDate; !cursor.After(endDate); cursor = cursor.AddDate(0, 0, 1) {
		dates = append(dates, cursor.Format("2006-01-02"))
	}
	return dates, ""
}

// scPlanNoEndDate 无期限方案的结束日期哨兵：数据库日期列不支持空串，
// 统一存 2099-12-31，前端按 no_end 标记展示为「无期限」。
const scPlanNoEndDate = "2099-12-31"

// scDateSpanUnbounded 展开任意长度的日期区间，供无期限方案的
// 「当年窗口」使用，不受 scDateSpan 的 92 天上限约束。
func scDateSpanUnbounded(start, end string) ([]string, string) {
	startDate, ok := scParseDate(start)
	if !ok {
		return nil, "开始日期格式错误"
	}
	endDate, ok := scParseDate(end)
	if !ok {
		return nil, "结束日期格式错误"
	}
	if endDate.Before(startDate) {
		return nil, "结束日期不能早于开始日期"
	}
	total := int(endDate.Sub(startDate).Hours()/24) + 1
	dates := make([]string, 0, total)
	for cursor := startDate; !cursor.After(endDate); cursor = cursor.AddDate(0, 0, 1) {
		dates = append(dates, cursor.Format("2006-01-02"))
	}
	return dates, ""
}

// scIsNoEnd 判断结束日期是否表示无期限（空串或哨兵值）。
func scIsNoEnd(end string) bool {
	return end == "" || end >= scPlanNoEndDate
}

// scPlanGenWindow 计算一次预览 / 发布实际展开的日期窗口。
// 普通方案：[start, end] 原样展开；无期限方案：从 max(start, 今天) 生成到
// 当年 12 月 31 日，跨年不自动延续，新的一年需要重新排班。
func scPlanGenWindow(startText, endText string) ([]string, string) {
	if !scIsNoEnd(endText) {
		return scDateSpan(startText, endText)
	}
	startDate, ok := scParseDate(startText)
	if !ok {
		return nil, "开始日期格式错误"
	}
	windowStart := startDate
	today := time.Now()
	if today.After(startDate) {
		windowStart = today
	}
	windowEnd := time.Date(today.Year(), 12, 31, 0, 0, 0, 0, today.Location())
	if windowEnd.Before(windowStart) {
		windowEnd = windowStart
	}
	return scDateSpanUnbounded(windowStart.Format("2006-01-02"), windowEnd.Format("2006-01-02"))
}

// scMinutes 把 "HH:mm" 转为当日分钟数。
func scMinutes(value string) (int, bool) {
	if value == "" {
		return 0, false
	}
	parsed, err := time.ParseInLocation("15:04", value, time.Local)
	if err != nil {
		return 0, false
	}
	return parsed.Hour()*60 + parsed.Minute(), true
}

// scCalcWorkHours 计算班次工时（小时）：上下班跨度扣除休息时段。
// 下班时间早于上班时间视为跨天班次，自动加 24 小时。
func scCalcWorkHours(workStart, workEnd, restStart, restEnd string) float64 {
	start, okStart := scMinutes(workStart)
	end, okEnd := scMinutes(workEnd)
	if !okStart || !okEnd {
		return 0
	}
	if end <= start {
		end += 24 * 60
	}
	span := end - start
	if restStart != "" && restEnd != "" {
		restFrom, okFrom := scMinutes(restStart)
		restTo, okTo := scMinutes(restEnd)
		if okFrom && okTo {
			if restTo <= restFrom {
				restTo += 24 * 60
			}
			if restTo > start && restFrom < end {
				overlap := restTo - restFrom
				if restFrom < start {
					overlap -= start - restFrom
				}
				if restTo > end {
					overlap -= restTo - end
				}
				if overlap > 0 {
					span -= overlap
				}
			}
		}
	}
	if span < 0 {
		return 0
	}
	return float64(span) / 60
}

// ---------------------------------------------------------------------------
// 班次管理
// ---------------------------------------------------------------------------

func (c *BackendOaSchedulingController) shiftQuery(tid uint64) orm.QuerySeter {
	return models.Orm.QueryTable(new(models.OaShift)).
		Filter("tid", tid).
		Filter("is_deleted", 0)
}

func (c *BackendOaSchedulingController) shiftByID(tid, id uint64) (*models.OaShift, bool) {
	var row models.OaShift
	if err := c.shiftQuery(tid).Filter("id", id).One(&row); err != nil {
		return nil, false
	}
	return &row, true
}

// ShiftList 班次列表。
// GET /backend/oa/scheduling/shifts
func (c *BackendOaSchedulingController) ShiftList() {
	tid, _, _, ok := c.scOperator()
	if !ok {
		return
	}

	var rows []models.OaShift
	if _, err := c.shiftQuery(tid).OrderBy("sort", "id").All(&rows); err != nil {
		c.scFail(500, 500, "查询班次失败: "+err.Error())
		return
	}
	if rows == nil {
		rows = []models.OaShift{}
	}

	var defaultID uint64
	for _, row := range rows {
		if row.IsDefault == 1 {
			defaultID = row.ID
			break
		}
	}

	c.scOK(map[string]interface{}{
		"list":       rows,
		"default_id": defaultID,
		"total":      len(rows),
	})
}

// CreateShift 新增班次。
// POST /backend/oa/scheduling/shifts
func (c *BackendOaSchedulingController) CreateShift() {
	tid, _, _, ok := c.scOperator()
	if !ok {
		return
	}
	body := c.scBody()

	row, msg := c.buildShiftFromBody(body)
	if msg != "" {
		c.scFail(400, 400, msg)
		return
	}
	row.Tid = int(tid)

	if row.IsDefault == 1 {
		c.clearDefaultShift(tid, 0)
	}
	if _, err := models.Orm.Insert(row); err != nil {
		c.scFail(500, 500, "新增班次失败: "+err.Error())
		return
	}

	c.scOK(row)
}

// UpdateShift 更新班次。
// POST /backend/oa/scheduling/shifts/:id
func (c *BackendOaSchedulingController) UpdateShift() {
	tid, _, _, ok := c.scOperator()
	if !ok {
		return
	}
	id, valid := c.scPathID(":id")
	if !valid {
		c.scFail(400, 400, "无效的班次ID")
		return
	}
	existing, found := c.shiftByID(tid, id)
	if !found {
		c.scFail(404, 404, "班次不存在")
		return
	}

	body := c.scBody()
	row, msg := c.buildShiftFromBody(body)
	if msg != "" {
		c.scFail(400, 400, msg)
		return
	}

	existing.Name = row.Name
	existing.ShortName = row.ShortName
	existing.Color = row.Color
	existing.WorkStart = row.WorkStart
	existing.WorkEnd = row.WorkEnd
	existing.RestStart = row.RestStart
	existing.RestEnd = row.RestEnd
	existing.WorkHours = row.WorkHours
	existing.IsDefault = row.IsDefault
	existing.Status = row.Status
	existing.Sort = row.Sort
	existing.Remark = row.Remark

	if existing.IsDefault == 1 {
		c.clearDefaultShift(tid, existing.ID)
	}
	if _, err := models.Orm.Update(existing); err != nil {
		c.scFail(500, 500, "更新班次失败: "+err.Error())
		return
	}

	// 班次名称/时间变化时同步已排班的快照，避免看板显示旧时间。
	c.syncShiftSnapshot(tid, existing)

	c.scOK(existing)
}

// DeleteShift 删除班次（软删除）。已被排班使用时拒绝删除，建议改为停用。
// DELETE /backend/oa/scheduling/shifts/:id
func (c *BackendOaSchedulingController) DeleteShift() {
	tid, _, _, ok := c.scOperator()
	if !ok {
		return
	}
	id, valid := c.scPathID(":id")
	if !valid {
		c.scFail(400, 400, "无效的班次ID")
		return
	}
	row, found := c.shiftByID(tid, id)
	if !found {
		c.scFail(404, 404, "班次不存在")
		return
	}

	used, _ := models.Orm.QueryTable(new(models.OaScheduleEntry)).
		Filter("tid", tid).
		Filter("shift_id", id).
		Filter("is_deleted", 0).
		Count()
	if used > 0 {
		c.scFail(400, 400, "该班次已被排班使用，无法删除，请改为停用")
		return
	}

	now := time.Now()
	row.IsDeleted = 1
	row.DeleteTime = &now
	if _, err := models.Orm.Update(row, "is_deleted", "delete_time"); err != nil {
		c.scFail(500, 500, "删除班次失败: "+err.Error())
		return
	}
	c.scOK(map[string]interface{}{"id": id})
}

// buildShiftFromBody 校验并构造班次对象；返回非空 msg 表示参数错误。
func (c *BackendOaSchedulingController) buildShiftFromBody(body map[string]interface{}) (*models.OaShift, string) {
	name := scStringValue(body, "name")
	if name == "" {
		return nil, "班次名称不能为空"
	}
	if len([]rune(name)) > 50 {
		return nil, "班次名称不能超过 50 个字符"
	}

	workStart := scStringValue(body, "work_start")
	workEnd := scStringValue(body, "work_end")
	if !isValidOaTime(workStart) || !isValidOaTime(workEnd) {
		return nil, "上下班时间格式应为 HH:mm"
	}
	if workStart == workEnd {
		return nil, "上下班时间不能相同"
	}

	restStart := scStringValue(body, "rest_start")
	restEnd := scStringValue(body, "rest_end")
	if (restStart == "") != (restEnd == "") {
		return nil, "休息开始与结束时间需要同时填写"
	}
	if restStart != "" && (!isValidOaTime(restStart) || !isValidOaTime(restEnd)) {
		return nil, "休息时间格式应为 HH:mm"
	}

	shortName := scStringValue(body, "short_name")
	if shortName == "" {
		shortName = name
	}
	color := scStringValue(body, "color")
	if color == "" {
		color = "#409EFF"
	}
	status := int8(1)
	if value, has := scIntValue(body, "status"); has {
		status = int8(value)
	}
	sortValue, _ := scIntValue(body, "sort")
	isDefault := int8(0)
	if scBoolValue(body, "is_default") {
		isDefault = 1
	}
	remark := scStringValue(body, "remark")
	row := &models.OaShift{
		Name:      name,
		ShortName: shortName,
		Color:     color,
		WorkStart: workStart,
		WorkEnd:   workEnd,
		RestStart: restStart,
		RestEnd:   restEnd,
		WorkHours: scCalcWorkHours(workStart, workEnd, restStart, restEnd),
		IsDefault: isDefault,
		Status:    status,
		Sort:      sortValue,
	}
	if remark != "" {
		row.Remark = &remark
	}
	return row, ""
}

// clearDefaultShift 把同租户下其它班次的默认标记清掉，保证只有一个默认班次。
func (c *BackendOaSchedulingController) clearDefaultShift(tid, excludeID uint64) {
	qs := c.shiftQuery(tid).Filter("is_default", 1)
	if excludeID > 0 {
		qs = qs.Exclude("id", excludeID)
	}
	var rows []models.OaShift
	if _, err := qs.All(&rows); err != nil {
		return
	}
	for i := range rows {
		rows[i].IsDefault = 0
		_, _ = models.Orm.Update(&rows[i], "is_default")
	}
}

// syncShiftSnapshot 班次变更后，把新快照写回已生成的排班明细。
func (c *BackendOaSchedulingController) syncShiftSnapshot(tid uint64, shift *models.OaShift) {
	_, _ = models.Orm.Raw(
		"UPDATE yz_backend_oa_schedule_entry SET shift_name=?, short_name=?, color=?, work_start=?, work_end=? "+
			"WHERE tid=? AND shift_id=? AND is_deleted=0",
		shift.Name, shift.ShortName, shift.Color, shift.WorkStart, shift.WorkEnd, tid, shift.ID,
	).Exec()
}