package repository

import (
	"errors"
	"strings"

	"hyapp-admin-server/internal/model"

	"gorm.io/gorm"
	"gorm.io/gorm/clause"
)

var ErrWithdrawalApplicationAlreadyAudited = errors.New("withdrawal application already audited")

type WithdrawalApplicationListOptions struct {
	Page     int
	PageSize int
	AppCode  string
	Keyword  string
}

type WithdrawalApplicationAuditInput struct {
	Decision           string
	ApproverUserID     uint
	ApproverName       string
	AuditRemark        string
	AuditImageURL      string
	AuditCommandID     string
	AuditTransactionID string
	ApprovedAtMS       int64
}

func (s *Store) GetWithdrawalApplication(id uint) (*model.UserWithdrawalApplication, error) {
	var application model.UserWithdrawalApplication
	if err := s.db.First(&application, id).Error; err != nil {
		return nil, err
	}
	return &application, nil
}

func (s *Store) GetWithdrawalApplicationForApp(appCode string, id uint) (*model.UserWithdrawalApplication, error) {
	var application model.UserWithdrawalApplication
	if err := s.db.Where("app_code = ? AND id = ?", strings.TrimSpace(appCode), id).First(&application).Error; err != nil {
		return nil, err
	}
	return &application, nil
}

func (s *Store) ListWithdrawalApplications(options WithdrawalApplicationListOptions) ([]model.UserWithdrawalApplication, int64, error) {
	page, pageSize := normalizePage(options.Page, options.PageSize)
	query := s.db.Model(&model.UserWithdrawalApplication{})
	query = applyWithdrawalApplicationFilters(query, options)

	var total int64
	if err := query.Count(&total).Error; err != nil {
		return nil, 0, err
	}
	var applications []model.UserWithdrawalApplication
	// 提现申请是财务审核场景，默认按最新申请优先展示；id 作为同毫秒写入时的稳定次序，避免分页翻页时记录抖动。
	err := query.
		Order("created_at_ms DESC, id DESC").
		Limit(pageSize).
		Offset((page - 1) * pageSize).
		Find(&applications).Error
	return applications, total, err
}

func (s *Store) AuditWithdrawalApplication(id uint, input WithdrawalApplicationAuditInput) (*model.UserWithdrawalApplication, error) {
	return s.AuditWithdrawalApplicationForApp("", id, input)
}

func (s *Store) AuditWithdrawalApplicationForApp(appCode string, id uint, input WithdrawalApplicationAuditInput) (*model.UserWithdrawalApplication, error) {
	if id == 0 {
		return nil, errors.New("withdrawal application id is required")
	}
	if input.Decision != model.WithdrawalApplicationStatusApproved && input.Decision != model.WithdrawalApplicationStatusRejected {
		return nil, errors.New("withdrawal application decision is invalid")
	}

	var application model.UserWithdrawalApplication
	err := s.db.Transaction(func(tx *gorm.DB) error {
		// 审核只能从 pending 进入终态；行锁阻止两个财务同时覆盖同一张提现单的执行结果。
		query := tx.Clauses(clause.Locking{Strength: "UPDATE"})
		if strings.TrimSpace(appCode) != "" {
			// 后台按当前 App 上下文审核，不能只凭全局自增 ID 跨 App 锁定和审核提现单。
			query = query.Where("app_code = ?", strings.TrimSpace(appCode))
		}
		if err := query.First(&application, id).Error; err != nil {
			return err
		}
		if application.Status != model.WithdrawalApplicationStatusPending {
			return ErrWithdrawalApplicationAlreadyAudited
		}
		return tx.Model(&application).Updates(map[string]any{
			"status":               input.Decision,
			"approver_user_id":     input.ApproverUserID,
			"approver_name":        strings.TrimSpace(input.ApproverName),
			"audit_remark":         strings.TrimSpace(input.AuditRemark),
			"audit_image_url":      strings.TrimSpace(input.AuditImageURL),
			"audit_command_id":     strings.TrimSpace(input.AuditCommandID),
			"audit_transaction_id": strings.TrimSpace(input.AuditTransactionID),
			"approved_at_ms":       input.ApprovedAtMS,
			"updated_at_ms":        input.ApprovedAtMS,
		}).Error
	})
	if err != nil {
		return nil, err
	}
	if strings.TrimSpace(appCode) != "" {
		return s.GetWithdrawalApplicationForApp(appCode, id)
	}
	return s.GetWithdrawalApplication(id)
}

// ApprovedWithdrawalStats 按审批通过时间聚合用户提现申请的 USDT 金额。
// 旧工资提现用 withdraw_amount_minor 保存美分；Huwaa POINT 提现该字段保存 gross points，因此必须用 withdraw_amount 的 USD 展示值折算。
type ApprovedWithdrawalStats struct {
	ApprovedCount    int64
	ApprovedUSDMinor int64
}

func (s *Store) ApprovedWithdrawalStats(appCode string, startAtMS int64, endAtMS int64) (ApprovedWithdrawalStats, error) {
	query := s.db.Model(&model.UserWithdrawalApplication{}).
		Where("status = ?", model.WithdrawalApplicationStatusApproved)
	if appCode = strings.TrimSpace(appCode); appCode != "" {
		query = query.Where("app_code = ?", appCode)
	}
	if startAtMS > 0 {
		query = query.Where("approved_at_ms >= ?", startAtMS)
	}
	if endAtMS > 0 {
		query = query.Where("approved_at_ms < ?", endAtMS)
	}
	var stats ApprovedWithdrawalStats
	row := query.Select(`
		COUNT(*),
		COALESCE(SUM(CASE
			WHEN salary_asset_type IN ('POINT', 'COIN_SELLER_POINT') THEN CAST(withdraw_amount * 100 AS SIGNED)
			ELSE withdraw_amount_minor
		END), 0)`).Row()
	if err := row.Scan(&stats.ApprovedCount, &stats.ApprovedUSDMinor); err != nil {
		return ApprovedWithdrawalStats{}, err
	}
	return stats, nil
}

func applyWithdrawalApplicationFilters(query *gorm.DB, options WithdrawalApplicationListOptions) *gorm.DB {
	if appCode := strings.TrimSpace(options.AppCode); appCode != "" {
		query = query.Where("app_code = ?", appCode)
	}
	if keyword := strings.TrimSpace(options.Keyword); keyword != "" {
		like := "%" + keyword + "%"
		// 关键词面向财务排查，覆盖用户、收款方式、收款地址和审批人；不做金额模糊，避免 decimal 隐式转换拖慢常规查询。
		query = query.Where("user_id LIKE ? OR withdraw_method LIKE ? OR withdraw_address LIKE ? OR approver_name LIKE ? OR CAST(id AS CHAR) LIKE ?", like, like, like, like, like)
	}
	return query
}