package service

import (
	"context"

	"github.com/gogf/gf/v2/errors/gerror"
	"github.com/gogf/gf/v2/util/gconv"

	"cid/dao"
	"cid/model/dto"
	"cid/model/entity"
)

var Advertiser = new(advertiser)

type advertiser struct{}

// Add 添加广告主
func (s *advertiser) Add(ctx context.Context, req *dto.AddAdvertiserReq) (res *dto.AddAdvertiserRes, err error) {
	advertiser := &entity.Advertiser{}
	if err = gconv.Struct(req, advertiser); err != nil {
		return
	}

	// 设置初始状态
	advertiser.Status = "待审核"

	// 注意：CreatedAt、UpdatedAt、TenantId、IsDeleted等字段由common/mongo的Insert方法自动设置
	if err = dao.Advertiser.Insert(ctx, advertiser); err != nil {
		return
	}

	res = &dto.AddAdvertiserRes{Id: advertiser.Id.Hex()}
	return
}

// Update 更新广告主
func (s *advertiser) Update(ctx context.Context, req *dto.UpdateAdvertiserReq) (err error) {
	// 更新修改时间（不需要设置，DAO层会处理）
	return dao.Advertiser.Update(ctx, req)
}

// UpdateStatus 更新广告主状态
func (s *advertiser) UpdateStatus(ctx context.Context, req *dto.UpdateAdvertiserStatusReq) (err error) {
	return dao.Advertiser.UpdateStatus(ctx, req.Id, req.Status)
}

// Audit 审核广告主
func (s *advertiser) Audit(ctx context.Context, req *dto.AuditAdvertiserReq) (err error) {
	return dao.Advertiser.Audit(ctx, req.Id, req.AuditStatus, req.AuditReason)
}

// Recharge 充值
func (s *advertiser) Recharge(ctx context.Context, req *dto.RechargeAdvertiserReq) (err error) {
	// 验证金额
	if req.Amount <= 0 {
		return gerror.New("充值金额必须大于0")
	}

	// 执行充值
	err = dao.Advertiser.Recharge(ctx, req.Id, req.Amount, req.Remark)
	if err != nil {
		return
	}

	// 记录充值流水（实际项目中可能需要创建充值记录表）
	// 这里简化处理

	return
}

// UpdateCreditLimit 更新授信额度
func (s *advertiser) UpdateCreditLimit(ctx context.Context, req *dto.UpdateCreditLimitReq) (err error) {
	// 验证授信额度
	if req.CreditLimit < 0 {
		return gerror.New("授信额度不能为负数")
	}

	// 更新授信额度
	err = dao.Advertiser.UpdateCreditLimit(ctx, req.Id, req.CreditLimit)
	return
}

// GetOne 获取广告主详情
func (s *advertiser) GetOne(ctx context.Context, req *dto.GetAdvertiserReq) (res *dto.GetAdvertiserRes, err error) {
	advertiser, err := dao.Advertiser.GetOne(ctx, req.Id)
	if err != nil {
		return
	}

	res = &dto.GetAdvertiserRes{
		Advertiser: advertiser,
	}
	return
}

// List 获取广告主列表
func (s *advertiser) List(ctx context.Context, req *dto.ListAdvertiserReq) (res *dto.ListAdvertiserRes, err error) {
	list, total, err := dao.Advertiser.List(ctx, req)
	if err != nil {
		return
	}

	res = &dto.ListAdvertiserRes{
		List:  list,
		Total: int(total),
	}
	return
}

// GetBalance 获取广告主余额
func (s *advertiser) GetBalance(ctx context.Context, id string) (balance, creditLimit int64, err error) {
	advertiser, err := dao.Advertiser.GetOne(ctx, id)
	if err != nil {
		return
	}

	balance = advertiser.AccountBalance
	creditLimit = advertiser.CreditLimit
	return
}

// CheckBudget 检查广告主预算
func (s *advertiser) CheckBudget(ctx context.Context, id string, cost int64) (hasEnoughBudget bool, err error) {
	advertiser, err := dao.Advertiser.GetOne(ctx, id)
	if err != nil {
		return
	}

	// 可用金额 = 账户余额 + 授信额度 - 已消耗
	availableAmount := advertiser.AccountBalance + advertiser.CreditLimit

	// 检查预算是否充足
	hasEnoughBudget = availableAmount >= cost

	return
}

// DeductBudget 扣除预算
func (s *advertiser) DeductBudget(ctx context.Context, id string, cost int64) (err error) {
	// 检查预算是否充足
	hasEnoughBudget, err := s.CheckBudget(ctx, id, cost)
	if err != nil {
		return
	}

	if !hasEnoughBudget {
		return gerror.New("预算不足")
	}

	// 获取广告主信息
	advertiser, err := dao.Advertiser.GetOne(ctx, id)
	if err != nil {
		return
	}

	// 计算新余额
	newBalance := advertiser.AccountBalance - cost

	// 如果账户余额为负，从授信额度中扣除
	if newBalance < 0 {
		newCreditLimit := advertiser.CreditLimit + newBalance
		newBalance = 0

		// 更新授信额度
		err = dao.Advertiser.UpdateCreditLimit(ctx, id, newCreditLimit)
		if err != nil {
			return
		}
	}

	// 更新账户余额
	err = dao.Advertiser.Update(ctx, &dto.UpdateAdvertiserReq{
		Id:             id,
		AccountBalance: &newBalance,
	})
	return
}