package controllers

import (
	"fmt"
	"time"

	"server/models"
	"server/pkg/jwtutil"
	"server/services"
	approvalEngine "server/services/approval"

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

// reimburse_approval_core.go 报销单「审批人视角」操作共享逻辑。
//
// Web 端（/backend/reimbursements/approve|reject|my-approve-task）与
// 小程序端（/api/oa/expense/approve|reject|my-approve-task）共用本文件；
// 审批中心 TaskAct 也复用其中的 biz_type 判定与时间线回写。

// isReimburseBizType 判断审批任务/实例是否属于报销类单据。
func isReimburseBizType(bizType string) bool {
	return approvalEngine.IsReimburseBizType(bizType)
}

// claimsReimburseUIDs 当前登录用户可能出现在 approver_id 上的两种口径：
// 认证中心 identity_id 与本租户 uid（历史上两种写法并存，这里都兼容）。
func claimsReimburseUIDs(claims *jwtutil.Claims) []interface{} {
	raw := uint64(claims.UserID)
	out := []interface{}{raw}
	if uid := services.ResolveTenantUID(uint64(claims.TenantId), raw); uid != raw {
		out = append(out, uid)
	}
	return out
}

// reimburseMyTaskCore 查当前用户在报销单 id 上的待办审批任务；无待办返回 (nil, nil)。
func reimburseMyTaskCore(claims *jwtutil.Claims, id uint64) (*models.ApprovalTask, error) {
	tid := uint64(claims.TenantId)
	var task models.ApprovalTask
	err := models.Orm.QueryTable(new(models.ApprovalTask)).
		Filter("scope", models.ApprovalScopeTenant).
		Filter("tid", tid).
		Filter("biz_type", models.ApprovalBizReimburse).
		Filter("biz_id", id).
		Filter("status", models.ApprovalTaskPending).
		Filter("is_deleted", 0).
		Filter("approver_id__in", claimsReimburseUIDs(claims)...).
		OrderBy("-id").One(&task)
	if err == orm.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	return &task, nil
}

// reimburseActCore 报销单审批操作共享逻辑（pass=true 通过 / false 驳回）。
//
// 返回 (httpCode, errMsg, hint)：errMsg 非空表示失败；成功时 hint 为提示文案。
// 节点流转交由统一审批引擎，本函数负责定位当前用户的待办任务并补记业务时间线。
func reimburseActCore(claims *jwtutil.Claims, id uint64, pass bool, comment string) (int, string, string) {
	if _, err := findOwnedReimbursement(claims, id); err != nil {
		return 404, "报销单不存在", ""
	}
	task, err := reimburseMyTaskCore(claims, id)
	if err != nil {
		return 500, "查询审批任务失败", ""
	}
	if task == nil {
		return 400, "当前没有待您审批的节点", ""
	}

	result, err := approvalEngine.Approve(task.ID, approvalEngine.ApproveInput{
		ApproverID: task.ApproverID,
		Pass:       pass,
		Comment:    comment,
	})
	if err != nil {
		return 400, err.Error(), ""
	}

	applyReimburseApprovalResult(uint64(claims.TenantId), id,
		uint64(claims.UserID), reimburseActorName(uint64(claims.TenantId), claims), task.Sort,
		pass, comment, result.Finished, result.InstanceStat)

	hint := result.Message
	if hint == "" {
		if pass {
			hint = "审批通过"
		} else {
			hint = "已驳回"
		}
	}
	return 200, "", hint
}

// applyReimburseApprovalResult 把一次审批动作回写到报销业务侧：
// 补记 yz_backend_approval_records 时间线；流程结束时同步单据终态（引擎的
// SyncBizResult 也会做同样的事，这里按终态幂等，避免重复插记录）。
func applyReimburseApprovalResult(tid, bizID, actorID uint64, actorName string, step int,
	pass bool, comment string, finished bool, instStatus int8) {
	if tid == 0 || bizID == 0 {
		return
	}
	action := int8(models.ApprovalActionApprove)
	if !pass {
		action = models.ApprovalActionReject
	}

	var row models.BackendReimbursement
	if err := models.Orm.QueryTable(new(models.BackendReimbursement)).
		Filter("id", bizID).Filter("tid", tid).Filter("is_deleted", 0).One(&row); err != nil {
		return
	}

	// 终态同步（审批中→通过/驳回），引擎已同步过则跳过
	var bizStatus int8
	if finished {
		switch instStatus {
		case models.ApprovalInstanceApproved:
			bizStatus = 2
		case models.ApprovalInstanceRejected:
			bizStatus = 3
		}
		if bizStatus != 0 && row.Status != bizStatus {
			_, _ = models.Orm.QueryTable(new(models.BackendReimbursement)).
				Filter("id", bizID).Filter("tid", tid).
				Update(orm.Params{"status": bizStatus, "current_approver_id": 0, "update_time": time.Now()})
		}
	}

	// 时间线去重：同一步骤同一动作只记一次
	dup := models.Orm.QueryTable(new(models.BackendApprovalRecord)).
		Filter("tid", tid).Filter("reimbursement_id", bizID).
		Filter("approver_id", actorID).Filter("action", action).
		Filter("step", int8(step)).Filter("is_deleted", 0).Exist()
	if dup {
		return
	}
	var commentPtr *string
	if comment != "" {
		commentPtr = &comment
	}
	_, _ = models.Orm.Insert(&models.BackendApprovalRecord{
		Tid: tid, UID: uint64Ptr(actorID), ReimbursementID: bizID,
		ApproverID: actorID, ApproverName: fmt.Sprintf("%s", actorName), Action: action,
		Comment: commentPtr, Step: int8(step), PrevStep: int8(step),
	})
}