package service

import (
	"context"
	"database/sql"
	"time"

	"bdrp-server/app/main/model"
	"bdrp-server/common/globalkey"
)

// IsMembershipExpired 判断代理会员是否已过期（仅VIP/SVIP会被判定）
func IsMembershipExpired(agent *model.Agent, now time.Time) bool {
	if agent == nil {
		return false
	}
	if agent.LevelName != model.AgentLeveNameVIP && agent.LevelName != model.AgentLeveNameSVIP {
		return false
	}
	if !agent.MembershipExpiryTime.Valid {
		return true
	}
	return !agent.MembershipExpiryTime.Time.After(now)
}

// DowngradeExpiredMembership 将已过期会员降级为普通代理，返回是否发生了降级
func DowngradeExpiredMembership(ctx context.Context, agentModel model.AgentModel, agentID int64, now time.Time) (bool, error) {
	agent, err := agentModel.FindOne(ctx, agentID)
	if err != nil {
		return false, err
	}
	if !IsMembershipExpired(agent, now) {
		return false, nil
	}
	agent.LevelName = model.AgentLeveNameNormal
	ClearMembershipOnDowngrade(agent)
	agent.UpdateTime = now
	if err = agentModel.UpdateWithVersion(ctx, nil, agent); err != nil {
		return false, err
	}
	return true, nil
}

// ListTodayWillExpireAgents 查询当天将到期的VIP/SVIP代理
func ListTodayWillExpireAgents(ctx context.Context, agentModel model.AgentModel, start, end time.Time) ([]*model.Agent, error) {
	builder := agentModel.SelectBuilder().
		Where("level_name IN (?, ?)", model.AgentLeveNameVIP, model.AgentLeveNameSVIP).
		Where("membership_expiry_time IS NOT NULL").
		Where("membership_expiry_time >= ?", start).
		Where("membership_expiry_time <= ?", end).
		Where("del_state = ?", globalkey.DelStateNo)

	return agentModel.FindAll(ctx, builder, "membership_expiry_time ASC")
}

// ListExpiredUnprocessedAgents 查询已过期但仍为VIP/SVIP的代理
func ListExpiredUnprocessedAgents(ctx context.Context, agentModel model.AgentModel, now time.Time) ([]*model.Agent, error) {
	builder := agentModel.SelectBuilder().
		Where("level_name IN (?, ?)", model.AgentLeveNameVIP, model.AgentLeveNameSVIP).
		Where("membership_expiry_time IS NOT NULL").
		Where("membership_expiry_time <= ?", now).
		Where("del_state = ?", globalkey.DelStateNo)

	return agentModel.FindAll(ctx, builder, "membership_expiry_time ASC")
}

// ClearMembershipOnDowngrade 降级时清理会员有效期，避免脏状态
func ClearMembershipOnDowngrade(agent *model.Agent) {
	agent.MembershipExpiryTime = sql.NullTime{}
}