package distribution

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"strings"
	"time"

	"hfb_sys/backend/internal/auditlog"
	"hfb_sys/backend/internal/model"

	"github.com/redis/go-redis/v9"
	"golang.org/x/crypto/bcrypt"
	"gorm.io/gorm"
	"gorm.io/gorm/clause"
)

var (
	ErrSiteNotFound            = errors.New("distribution site not found")
	ErrRuleNotFound            = errors.New("distribution rule not found")
	ErrOrderNotFound           = errors.New("distribution order not found")
	ErrInvalidOrderKind        = errors.New("invalid distribution order kind")
	ErrAccountDisplayNotFound  = errors.New("distribution account display not found")
	ErrPaymentChannelNotFound  = errors.New("distribution payment channel not found")
	ErrInvalidPeriod           = errors.New("invalid distribution settlement period")
	ErrSettlementBatchNotFound = errors.New("distribution settlement batch not found")
	ErrBatchAlreadySettled     = errors.New("distribution settlement batch already settled")
	ErrSettlementBatchEmpty    = errors.New("distribution settlement batch empty")
	ErrSettlementTotalMismatch = errors.New("distribution settlement total mismatch")
	ErrPaymentConfigNotFound     = errors.New("distribution payment config not found")
	ErrOrderSnapshotExists       = errors.New("distribution order snapshot exists")
	ErrSiteAccessDenied          = errors.New("distribution site access denied")
	ErrInvalidCredential         = errors.New("invalid credential")
	ErrAdminDisabled             = errors.New("admin disabled")
	ErrDuplicateSiteCodeOrDomain = errors.New("distribution site code or domain already exists")
	ErrDuplicateUsername         = errors.New("username already exists")
)

type Repository struct {
	db    *gorm.DB
	redis *redis.Client
}

func NewRepository(db *gorm.DB, redis ...*redis.Client) *Repository {
	r := &Repository{db: db}
	if len(redis) > 0 {
		r.redis = redis[0]
	}
	return r
}

func (r *Repository) ScopeSiteID(ctx context.Context, adminID, requested uint64) (uint64, error) {
	if adminID == 0 {
		return requested, nil
	}
	var members []model.DistributionSiteMember
	if err := r.db.WithContext(ctx).Where("admin_user_id = ? AND status = 'active'", adminID).Find(&members).Error; err != nil {
		return 0, err
	}
	if len(members) == 0 {
		return requested, nil
	}
	if requested > 0 {
		for _, member := range members {
			if member.SiteID == requested {
				return requested, nil
			}
		}
		return 0, ErrSiteAccessDenied
	}
	if len(members) == 1 {
		return members[0].SiteID, nil
	}
	return 0, nil
}

// ensureSiteAccess 校验管理员可访问指定站点：
// 无成员记录（超级管理员语义）放行，有成员记录则必须命中。
func (r *Repository) ensureSiteAccess(ctx context.Context, adminID, siteID uint64) error {
	if adminID == 0 {
		return nil
	}
	var count int64
	if err := r.db.WithContext(ctx).Model(&model.DistributionSiteMember{}).
		Where("admin_user_id = ? AND status = 'active'", adminID).Count(&count).Error; err != nil {
		return err
	}
	if count == 0 {
		return nil
	}
	if siteID == 0 {
		return ErrSiteAccessDenied
	}
	var allowed int64
	if err := r.db.WithContext(ctx).Model(&model.DistributionSiteMember{}).
		Where("admin_user_id = ? AND site_id = ? AND status = 'active'", adminID, siteID).Count(&allowed).Error; err != nil {
		return err
	}
	if allowed == 0 {
		return ErrSiteAccessDenied
	}
	return nil
}

func (r *Repository) ListSites(ctx context.Context) ([]SiteDTO, error) {
	var rows []model.DistributionSite
	if err := r.db.WithContext(ctx).Order("id ASC").Find(&rows).Error; err != nil {
		return nil, err
	}
	items := make([]SiteDTO, 0, len(rows))
	for _, row := range rows {
		items = append(items, siteDTO(row))
	}
	return items, nil
}

func (r *Repository) FindSite(ctx context.Context, adminID, id uint64) (*SiteDTO, error) {
	var row model.DistributionSite
	if err := r.db.WithContext(ctx).First(&row, id).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, ErrSiteNotFound
		}
		return nil, err
	}
	if err := r.ensureSiteAccess(ctx, adminID, row.ID); err != nil {
		return nil, err
	}
	item := siteDTO(row)
	return &item, nil
}

func (r *Repository) CreateSite(ctx context.Context, req CreateSiteRequest) (*SiteDTO, error) {
	row := model.DistributionSite{
		SiteCode: strings.TrimSpace(req.SiteCode), SiteName: strings.TrimSpace(req.SiteName), Domain: strings.TrimSpace(req.Domain),
		Status: "active", DisplayAccountEnabled: true, TaxRateBPS: 100,
	}
	if req.DisplayAccountEnabled != nil {
		row.DisplayAccountEnabled = *req.DisplayAccountEnabled
	}
	if req.DefaultSupportGroupID != nil {
		row.DefaultSupportGroupID = req.DefaultSupportGroupID
	}
	if req.TaxEnabled != nil {
		row.TaxEnabled = *req.TaxEnabled
	}
	if req.TaxRateBPS != nil {
		row.TaxRateBPS = *req.TaxRateBPS
	}
	if err := r.db.WithContext(ctx).Create(&row).Error; err != nil {
		return nil, err
	}
	item := siteDTO(row)
	return &item, nil
}

func (r *Repository) UpdateSite(ctx context.Context, adminID, id uint64, req UpdateSiteRequest) (*SiteDTO, error) {
	var row model.DistributionSite
	if err := r.db.WithContext(ctx).First(&row, id).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, ErrSiteNotFound
		}
		return nil, err
	}
	if err := r.ensureSiteAccess(ctx, adminID, row.ID); err != nil {
		return nil, err
	}
	if req.SiteName != nil {
		row.SiteName = strings.TrimSpace(*req.SiteName)
	}
	if req.Domain != nil {
		row.Domain = strings.TrimSpace(*req.Domain)
	}
	if req.Status != nil {
		row.Status = strings.TrimSpace(*req.Status)
	}
	if req.DisplayAccountEnabled != nil {
		row.DisplayAccountEnabled = *req.DisplayAccountEnabled
	}
	if req.DefaultSupportGroupID != nil {
		row.DefaultSupportGroupID = req.DefaultSupportGroupID
	}
	if req.TaxEnabled != nil {
		row.TaxEnabled = *req.TaxEnabled
	}
	if req.TaxRateBPS != nil {
		row.TaxRateBPS = *req.TaxRateBPS
	}
	if err := r.db.WithContext(ctx).Save(&row).Error; err != nil {
		return nil, err
	}
	item := siteDTO(row)
	return &item, nil
}

func (r *Repository) ListRules(ctx context.Context, adminID uint64, siteID *uint64, mode string) ([]RuleDTO, error) {
	db := r.db.WithContext(ctx).Model(&model.DistributionRuleVersion{}).Order("effective_from DESC, id DESC")
	if siteID == nil {
		db = db.Where("site_id IS NULL")
	} else {
		if err := r.ensureSiteAccess(ctx, adminID, *siteID); err != nil {
			return nil, err
		}
		db = db.Where("site_id = ?", *siteID)
	}
	if mode = strings.TrimSpace(mode); mode != "" {
		db = db.Where("mode = ?", mode)
	}
	var rows []model.DistributionRuleVersion
	if err := db.Find(&rows).Error; err != nil {
		return nil, err
	}
	items := make([]RuleDTO, 0, len(rows))
	for _, row := range rows {
		items = append(items, ruleDTO(row))
	}
	return items, nil
}

func (r *Repository) CreateRule(ctx context.Context, adminID uint64, req CreateRuleRequest) (*RuleDTO, error) {
	if req.SiteID != nil {
		if err := r.ensureSiteAccess(ctx, adminID, *req.SiteID); err != nil {
			return nil, err
		}
	}
	version := 1
	var maxVersion int
	db := r.db.WithContext(ctx).Model(&model.DistributionRuleVersion{}).Where("mode = ?", req.Mode)
	if req.SiteID == nil {
		db = db.Where("site_id IS NULL")
	} else {
		db = db.Where("site_id = ?", *req.SiteID)
	}
	if err := db.Select("COALESCE(MAX(version), 0)").Scan(&maxVersion).Error; err != nil {
		return nil, err
	}
	version = maxVersion + 1
	effectiveFrom := req.EffectiveFrom
	if effectiveFrom.IsZero() {
		effectiveFrom = time.Now()
	}
	row := model.DistributionRuleVersion{
		SiteID: req.SiteID, Mode: strings.TrimSpace(req.Mode), Version: version, Status: "draft",
		PlatformReceiveRatio: req.PlatformReceiveRatio, PlatformSellRatio: req.PlatformSellRatio,
		DistributorReceiveRatio: req.DistributorReceiveRatio, DistributorSellRatio: req.DistributorSellRatio,
		DistributorARatio: req.DistributorARatio, DistributorBRatio: req.DistributorBRatio,
		ServiceFeeValue: req.ServiceFeeValue, ServiceFeeUnit: strings.TrimSpace(req.ServiceFeeUnit),
		PaymentFeeBPS: req.PaymentFeeBPS, TaxEnabled: req.TaxEnabled, TaxRateBPS: req.TaxRateBPS,
		EffectiveFrom: effectiveFrom, CreatedBy: &adminID,
	}
	if row.PaymentFeeBPS == 0 {
		row.PaymentFeeBPS = 50
	}
	if row.TaxRateBPS == 0 {
		row.TaxRateBPS = 100
	}
	if err := r.db.WithContext(ctx).Create(&row).Error; err != nil {
		return nil, err
	}
	item := ruleDTO(row)
	return &item, nil
}

func (r *Repository) UpdateRuleStatus(ctx context.Context, adminID, id uint64, status string) (*RuleDTO, error) {
	var row model.DistributionRuleVersion
	if err := r.db.WithContext(ctx).First(&row, id).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, ErrRuleNotFound
		}
		return nil, err
	}
	if row.SiteID != nil {
		if err := r.ensureSiteAccess(ctx, adminID, *row.SiteID); err != nil {
			return nil, err
		}
	}
	row.Status = strings.TrimSpace(status)
	if err := r.db.WithContext(ctx).Save(&row).Error; err != nil {
		return nil, err
	}
	item := ruleDTO(row)
	return &item, nil
}

func siteDTO(row model.DistributionSite) SiteDTO {
	return SiteDTO{ID: row.ID, SiteCode: row.SiteCode, SiteName: row.SiteName, Domain: row.Domain, Status: row.Status, DisplayAccountEnabled: row.DisplayAccountEnabled, DefaultSupportGroupID: row.DefaultSupportGroupID, TaxEnabled: row.TaxEnabled, TaxRateBPS: row.TaxRateBPS, CreatedAt: row.CreatedAt, UpdatedAt: row.UpdatedAt}
}

func ruleDTO(row model.DistributionRuleVersion) RuleDTO {
	return RuleDTO{ID: row.ID, SiteID: row.SiteID, Mode: row.Mode, Version: row.Version, Status: row.Status, PlatformReceiveRatio: row.PlatformReceiveRatio, PlatformSellRatio: row.PlatformSellRatio, DistributorReceiveRatio: row.DistributorReceiveRatio, DistributorSellRatio: row.DistributorSellRatio, DistributorARatio: row.DistributorARatio, DistributorBRatio: row.DistributorBRatio, ServiceFeeValue: row.ServiceFeeValue, ServiceFeeUnit: row.ServiceFeeUnit, PaymentFeeBPS: row.PaymentFeeBPS, TaxEnabled: row.TaxEnabled, TaxRateBPS: row.TaxRateBPS, EffectiveFrom: row.EffectiveFrom, EffectiveTo: row.EffectiveTo, CreatedBy: row.CreatedBy, CreatedAt: row.CreatedAt}
}

func (r *Repository) ListOrders(ctx context.Context, query DistributionOrderListQuery) (*DistributionOrderPage, error) {
	page, size := query.Page, query.Size
	if page < 1 {
		page = 1
	}
	if size < 1 {
		size = 20
	}
	if size > 100 {
		size = 100
	}
	base := r.db.WithContext(ctx).Table("rental_orders ro").Joins("JOIN distribution_order_financials f ON f.order_id = ro.id")
	if query.SiteID > 0 {
		base = base.Where("ro.distribution_site_id = ?", query.SiteID)
	}
	if query.Status != "" {
		base = base.Where("ro.status = ?", query.Status)
	}
	switch strings.TrimSpace(query.Kind) {
	case "sold":
		base = base.Where("EXISTS (SELECT 1 FROM distribution_order_parties p WHERE p.order_id = ro.id AND p.party_role IN ('distributor_sell','distributor_b'))")
	case "receive":
		base = base.Where("EXISTS (SELECT 1 FROM distribution_order_parties p WHERE p.order_id = ro.id AND p.party_role IN ('distributor_receive','distributor_a'))")
	case "", "all":
	default:
		return nil, ErrInvalidOrderKind
	}
	var total int64
	if err := base.Session(&gorm.Session{}).Select("ro.id").Count(&total).Error; err != nil {
		return nil, err
	}
	items := make([]DistributionOrderDTO, 0)
	selectSQL := "ro.id AS order_id, ro.order_no, ro.distribution_site_id AS site_id, ro.listing_id, ro.account_id, ro.owner_id, ro.renter_id, ro.status, ro.handoff_status, ro.refund_status, ro.settlement_status, ro.distribution_mode, f.gross_paid_amount_cent, f.refund_amount_cent, f.net_paid_amount_cent, f.payment_fee_cent, f.service_fee_cent, f.markup_amount_cent, f.tax_amount_cent, f.split_base_amount_cent, f.rounding_adjustment_cent, ro.created_at"
	if err := base.Select(selectSQL).Order("ro.id DESC").Offset((page - 1) * size).Limit(size).Scan(&items).Error; err != nil {
		return nil, err
	}
	return &DistributionOrderPage{Items: items, Total: total, Page: page, PageSize: size}, nil
}

func (r *Repository) FindOrder(ctx context.Context, adminID, id uint64) (*DistributionOrderDTO, error) {
	var item DistributionOrderDTO
	err := r.db.WithContext(ctx).Table("rental_orders ro").Joins("JOIN distribution_order_financials f ON f.order_id = ro.id").Select("ro.id AS order_id, ro.order_no, ro.distribution_site_id AS site_id, ro.listing_id, ro.account_id, ro.owner_id, ro.renter_id, ro.status, ro.handoff_status, ro.refund_status, ro.settlement_status, ro.distribution_mode, f.gross_paid_amount_cent, f.refund_amount_cent, f.net_paid_amount_cent, f.payment_fee_cent, f.service_fee_cent, f.markup_amount_cent, f.tax_amount_cent, f.split_base_amount_cent, f.rounding_adjustment_cent, ro.created_at").Where("ro.id = ?", id).Scan(&item).Error
	if err != nil {
		return nil, err
	}
	if item.OrderID == 0 {
		return nil, ErrOrderNotFound
	}
	if err := r.ensureSiteAccess(ctx, adminID, item.SiteID); err != nil {
		return nil, err
	}
	return &item, nil
}

func (r *Repository) ListAccountDisplays(ctx context.Context, siteID uint64, status string) ([]AccountDisplayDTO, error) {
	var rows []model.DistributionSiteAccount
	db := r.db.WithContext(ctx).Where("site_id = ?", siteID).Order("id DESC")
	if status != "" {
		db = db.Where("display_status = ?", status)
	}
	if err := db.Find(&rows).Error; err != nil {
		return nil, err
	}
	items := make([]AccountDisplayDTO, 0, len(rows))
	for _, row := range rows {
		items = append(items, AccountDisplayDTO{ID: row.ID, SiteID: row.SiteID, AccountID: row.AccountID, ListingID: row.ListingID, DisplayStatus: row.DisplayStatus})
	}
	return items, nil
}

func (r *Repository) UpdateAccountDisplay(ctx context.Context, adminID, id uint64, status string) (*AccountDisplayDTO, error) {
	var row model.DistributionSiteAccount
	if err := r.db.WithContext(ctx).First(&row, id).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, ErrAccountDisplayNotFound
		}
		return nil, err
	}
	if err := r.ensureSiteAccess(ctx, adminID, row.SiteID); err != nil {
		return nil, err
	}
	row.DisplayStatus = strings.TrimSpace(status)
	if err := r.db.WithContext(ctx).Save(&row).Error; err != nil {
		return nil, err
	}
	item := &AccountDisplayDTO{ID: row.ID, SiteID: row.SiteID, AccountID: row.AccountID, ListingID: row.ListingID, DisplayStatus: row.DisplayStatus}
	return item, nil
}

func (r *Repository) ListPaymentChannels(ctx context.Context, siteID uint64) ([]PaymentChannelDTO, error) {
	var rows []model.DistributionSitePaymentChannel
	if err := r.db.WithContext(ctx).Where("site_id = ?", siteID).Order("priority ASC, id ASC").Find(&rows).Error; err != nil {
		return nil, err
	}
	items := make([]PaymentChannelDTO, 0, len(rows))
	for _, row := range rows {
		items = append(items, PaymentChannelDTO{ID: row.ID, SiteID: row.SiteID, ConfigID: row.ConfigID, Priority: row.Priority, Status: row.Status})
	}
	return items, nil
}

func (r *Repository) BindPaymentChannel(ctx context.Context, siteID uint64, req BindPaymentChannelRequest) (*PaymentChannelDTO, error) {
	var configCount int64
	if err := r.db.WithContext(ctx).Model(&model.PaymentMerchantConfig{}).
		Where("id = ?", req.ConfigID).Count(&configCount).Error; err != nil {
		return nil, err
	}
	if configCount == 0 {
		return nil, ErrPaymentConfigNotFound
	}
	row := model.DistributionSitePaymentChannel{SiteID: siteID, ConfigID: req.ConfigID, Priority: req.Priority, Status: "active"}
	if err := r.db.WithContext(ctx).Where("site_id = ? AND config_id = ?", siteID, req.ConfigID).FirstOrCreate(&row).Error; err != nil {
		return nil, err
	}
	return &PaymentChannelDTO{ID: row.ID, SiteID: row.SiteID, ConfigID: row.ConfigID, Priority: row.Priority, Status: row.Status}, nil
}

func (r *Repository) UnbindPaymentChannel(ctx context.Context, adminID, id uint64) error {
	var row model.DistributionSitePaymentChannel
	if err := r.db.WithContext(ctx).First(&row, id).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return ErrPaymentChannelNotFound
		}
		return err
	}
	if err := r.ensureSiteAccess(ctx, adminID, row.SiteID); err != nil {
		return err
	}
	return r.db.WithContext(ctx).Delete(&row).Error
}

func (r *Repository) ListSettlementBatches(ctx context.Context, siteID uint64) ([]SettlementBatchDTO, error) {
	var rows []model.DistributionSettlementBatch
	if err := r.db.WithContext(ctx).Where("site_id = ?", siteID).Order("id DESC").Find(&rows).Error; err != nil {
		return nil, err
	}
	items := make([]SettlementBatchDTO, 0, len(rows))
	for _, row := range rows {
		items = append(items, SettlementBatchDTO{ID: row.ID, SiteID: row.SiteID, BatchNo: row.BatchNo, PeriodStart: row.PeriodStart, PeriodEnd: row.PeriodEnd, TotalAmountCent: row.TotalAmountCent, Status: row.Status})
	}
	return items, nil
}

func (r *Repository) CreateSettlementBatch(ctx context.Context, adminID uint64, req CreateSettlementBatchRequest) (*SettlementBatchDTO, error) {
	if req.PeriodEnd.Before(req.PeriodStart) {
		return nil, ErrInvalidPeriod
	}
	if err := r.ensureSiteAccess(ctx, adminID, req.SiteID); err != nil {
		return nil, err
	}
	if req.SiteID == 0 {
		return nil, ErrInvalidPeriod
	}
	var batch model.DistributionSettlementBatch
	err := r.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
		batch = model.DistributionSettlementBatch{SiteID: req.SiteID, BatchNo: "DS" + time.Now().Format("20060102150405.000000000"), PeriodStart: req.PeriodStart, PeriodEnd: req.PeriodEnd, Status: "draft", CreatedBy: &adminID}
		if err := tx.Create(&batch).Error; err != nil {
			return err
		}
		// 聚合周期内尚未进入任何批次的待结算订单财务快照。
		var financials []model.DistributionOrderFinancial
		if err := tx.Where("site_id = ? AND settlement_status = 'pending'", req.SiteID).
			Where("created_at >= ? AND created_at < ?", req.PeriodStart, req.PeriodEnd).
			Where("NOT EXISTS (SELECT 1 FROM distribution_settlement_items i WHERE i.order_id = distribution_order_financials.order_id)").
			Order("id ASC").Find(&financials).Error; err != nil {
			return err
		}
		total := int64(0)
		for _, financial := range financials {
			var parties []model.DistributionOrderParty
			if err := tx.Where("order_id = ?", financial.OrderID).Find(&parties).Error; err != nil {
				return err
			}
			for _, party := range parties {
				item := model.DistributionSettlementItem{BatchID: batch.ID, OrderID: financial.OrderID, PartyID: party.ID, AmountCent: party.IncomeAmountCent, Status: "pending"}
				if err := tx.Create(&item).Error; err != nil {
					return err
				}
				total += party.IncomeAmountCent
			}
		}
		batch.TotalAmountCent = total
		return tx.Model(&model.DistributionSettlementBatch{}).Where("id = ?", batch.ID).
			Update("total_amount_cent", total).Error
	})
	if err != nil {
		return nil, err
	}
	return &SettlementBatchDTO{ID: batch.ID, SiteID: batch.SiteID, BatchNo: batch.BatchNo, PeriodStart: batch.PeriodStart, PeriodEnd: batch.PeriodEnd, TotalAmountCent: batch.TotalAmountCent, Status: batch.Status}, nil
}

func (r *Repository) MarkSettlementBatch(ctx context.Context, adminID, id uint64) (*SettlementBatchDTO, error) {
	var row model.DistributionSettlementBatch
	err := r.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
		if err := tx.Clauses(clause.Locking{Strength: "UPDATE"}).First(&row, id).Error; err != nil {
			if errors.Is(err, gorm.ErrRecordNotFound) {
				return ErrSettlementBatchNotFound
			}
			return err
		}
		if err := r.ensureSiteAccess(ctx, adminID, row.SiteID); err != nil {
			return err
		}
		if row.Status == "settled" {
			return ErrBatchAlreadySettled
		}
		var items []model.DistributionSettlementItem
		if err := tx.Where("batch_id = ?", row.ID).Find(&items).Error; err != nil {
			return err
		}
		if len(items) == 0 {
			return ErrSettlementBatchEmpty
		}
		var total int64
		for _, item := range items {
			total += item.AmountCent
		}
		if total != row.TotalAmountCent {
			return ErrSettlementTotalMismatch
		}
		now := time.Now()
		if err := tx.Model(&model.DistributionSettlementItem{}).Where("batch_id = ?", row.ID).
			Update("status", "settled").Error; err != nil {
			return err
		}
		if err := tx.Model(&model.DistributionOrderFinancial{}).
			Where("order_id IN (?)", tx.Model(&model.DistributionSettlementItem{}).
				Select("order_id").Where("batch_id = ?", row.ID)).
			Updates(map[string]any{"settlement_status": "settled", "settled_at": now}).Error; err != nil {
			return err
		}
		row.Status = "settled"
		row.SettledAt = &now
		return tx.Save(&row).Error
	})
	if err != nil {
		return nil, err
	}
	return &SettlementBatchDTO{ID: row.ID, SiteID: row.SiteID, BatchNo: row.BatchNo, PeriodStart: row.PeriodStart, PeriodEnd: row.PeriodEnd, TotalAmountCent: row.TotalAmountCent, Status: row.Status}, nil
}

func (r *Repository) CreateFinancialSnapshot(ctx context.Context, adminID, orderID uint64, req CreateFinancialSnapshotRequest) (*DistributionOrderDTO, error) {
	if req.SiteID == 0 || orderID == 0 {
		return nil, ErrInvalidAmount
	}
	if err := r.ensureSiteAccess(ctx, adminID, req.SiteID); err != nil {
		return nil, err
	}
	var rule model.DistributionRuleVersion
	if err := r.db.WithContext(ctx).First(&rule, req.RuleVersionID).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, ErrRuleNotFound
		}
		return nil, err
	}
	var orderExists int64
	if err := r.db.WithContext(ctx).Model(&model.RentalOrder{}).Where("id = ?", orderID).Count(&orderExists).Error; err != nil {
		return nil, err
	}
	if orderExists == 0 {
		return nil, ErrOrderNotFound
	}
	// 手工补数只允许创建，不允许覆盖支付事务写入的真实快照。
	var existing int64
	if err := r.db.WithContext(ctx).Model(&model.DistributionOrderFinancial{}).
		Where("order_id = ?", orderID).Count(&existing).Error; err != nil {
		return nil, err
	}
	if existing > 0 {
		return nil, ErrOrderSnapshotExists
	}
	partyInputs := make([]PartyProfitInput, 0, len(req.Parties))
	for _, party := range req.Parties {
		partyInputs = append(partyInputs, PartyProfitInput{PartyRole: party.PartyRole, IncomeAmountCent: party.IncomeAmountCent, CostAmountCent: party.CostAmountCent})
	}
	result, err := CalculateSettlement(Rule{Mode: rule.Mode, ServiceFeeValue: rule.ServiceFeeValue, ServiceFeeUnit: rule.ServiceFeeUnit, PaymentFeeBPS: rule.PaymentFeeBPS, TaxEnabled: rule.TaxEnabled, TaxRateBPS: rule.TaxRateBPS}, SettlementInput{GrossPaidAmountCent: req.GrossPaidAmountCent, RefundAmountCent: req.RefundAmountCent, MarkupAmountCent: req.MarkupAmountCent, GrossProfitByParty: partyInputs})
	if err != nil {
		return nil, err
	}
	err = r.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
		financial := model.DistributionOrderFinancial{OrderID: orderID, SiteID: req.SiteID, RuleVersionID: req.RuleVersionID, GrossPaidAmountCent: result.GrossPaidAmountCent, RefundAmountCent: result.RefundAmountCent, NetPaidAmountCent: result.NetPaidAmountCent, PaymentFeeBPS: rule.PaymentFeeBPS, PaymentFeeCent: result.PaymentFeeCent, ServiceFeeValue: rule.ServiceFeeValue, ServiceFeeUnit: rule.ServiceFeeUnit, ServiceFeeCent: result.ServiceFeeCent, MarkupAmountCent: result.MarkupAmountCent, TaxEnabled: rule.TaxEnabled, TaxRateBPS: rule.TaxRateBPS, TaxAmountCent: result.TaxAmountCent, SplitBaseAmountCent: result.SplitBaseAmountCent, RoundingAdjustmentCent: SplitRemainderCent(result.SplitBaseAmountCent, SplitSettlement(Rule{Mode: rule.Mode}, result.SplitBaseAmountCent, result.MarkupAmountCent)), SettlementStatus: "pending"}
		if err := tx.Create(&financial).Error; err != nil {
			return err
		}
		for idx, party := range req.Parties {
			tax := int64(0)
			if idx < len(result.TaxByParty) {
				tax = result.TaxByParty[idx].TaxAmountCent
			}
			profit := party.IncomeAmountCent - party.CostAmountCent
			row := model.DistributionOrderParty{OrderID: orderID, SiteID: req.SiteID, PartyRole: party.PartyRole, PartyType: party.PartyType, PartyID: party.PartyID, Ratio: party.Ratio, IncomeAmountCent: party.IncomeAmountCent, CostAmountCent: party.CostAmountCent, ProfitAmountCent: profit, TaxAmountCent: tax}
			if err := tx.Create(&row).Error; err != nil {
				return err
			}
		}
		if err := tx.Model(&model.RentalOrder{}).Where("id = ?", orderID).Updates(map[string]any{"distribution_site_id": req.SiteID, "distribution_rule_version_id": req.RuleVersionID}).Error; err != nil {
			return err
		}
		return auditlog.Append(tx, auditlog.Entry{
			ActorType: "admin", ActorID: adminID, Action: "distribution_financial_snapshot_create", BizType: "distribution_order", BizID: &orderID,
			Detail: map[string]any{"site_id": req.SiteID, "rule_version_id": req.RuleVersionID, "gross_paid_amount_cent": req.GrossPaidAmountCent, "refund_amount_cent": req.RefundAmountCent, "parties": len(req.Parties)},
		})
	})
	if err != nil {
		return nil, err
	}
	return r.FindOrder(ctx, adminID, orderID)
}

func (r *Repository) ListSettlementItems(ctx context.Context, adminID, batchID uint64) ([]SettlementItemDTO, error) {
	var batch model.DistributionSettlementBatch
	if err := r.db.WithContext(ctx).First(&batch, batchID).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, ErrSettlementBatchNotFound
		}
		return nil, err
	}
	if err := r.ensureSiteAccess(ctx, adminID, batch.SiteID); err != nil {
		return nil, err
	}
	var rows []struct {
		model.DistributionSettlementItem
		PartyRole string
	}
	if err := r.db.WithContext(ctx).
		Table("distribution_settlement_items i").
		Select("i.id, i.order_id, i.amount_cent, i.status, p.party_role").
		Joins("JOIN distribution_order_parties p ON p.id = i.party_id").
		Where("i.batch_id = ?", batchID).
		Order("i.id ASC").Scan(&rows).Error; err != nil {
		return nil, err
	}
	items := make([]SettlementItemDTO, 0, len(rows))
	for _, row := range rows {
		items = append(items, SettlementItemDTO{ID: row.ID, OrderID: row.OrderID, PartyRole: row.PartyRole, AmountCent: row.AmountCent, Status: row.Status})
	}
	return items, nil
}

func (r *Repository) LoginMember(ctx context.Context, username, password string) (*model.AdminUser, *DistributionCurrentMemberDTO, error) {
	if r.db == nil {
		return nil, nil, ErrDependencyUnavailable
	}
	var admin model.AdminUser
	if err := r.db.WithContext(ctx).Where("username = ?", username).First(&admin).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, nil, ErrInvalidCredential
		}
		return nil, nil, err
	}
	if admin.Status != "active" {
		return nil, nil, ErrAdminDisabled
	}
	if err := bcrypt.CompareHashAndPassword([]byte(admin.PasswordHash), []byte(password)); err != nil {
		return nil, nil, ErrInvalidCredential
	}

	var members []model.DistributionSiteMember
	if err := r.db.WithContext(ctx).Where("admin_user_id = ? AND status = 'active'", admin.ID).Find(&members).Error; err != nil {
		return nil, nil, err
	}

	dto := DistributionCurrentMemberDTO{
		AdminID:      admin.ID,
		Username:     admin.Username,
		Nickname:     admin.Nickname,
		IsSuperadmin: len(members) == 0,
	}
	if len(members) > 0 {
		var site model.DistributionSite
		if err := r.db.WithContext(ctx).First(&site, members[0].SiteID).Error; err == nil {
			dto.SiteID = &site.ID
			dto.SiteCode = site.SiteCode
			dto.SiteName = site.SiteName
			dto.Domain = site.Domain
			dto.MemberType = members[0].MemberType
		}
	}

	now := time.Now()
	admin.LastLoginAt = &now
	_ = r.db.WithContext(ctx).Model(&admin).Update("last_login_at", now).Error

	if r.redis != nil {
		if dto.IsSuperadmin {
			raw, _ := json.Marshal([]string{"*"})
			_ = r.redis.Set(ctx, fmt.Sprintf("admin:perms:%d", admin.ID), string(raw), 2*time.Hour).Err()
		} else {
			var permCodes []string
			if r.db != nil {
				_ = r.db.WithContext(ctx).Table("permissions").
					Select("DISTINCT permissions.code").
					Joins("JOIN role_permissions rp ON rp.permission_id = permissions.id").
					Joins("JOIN admin_user_roles aur ON aur.role_id = rp.role_id").
					Where("aur.admin_user_id = ?", admin.ID).
					Pluck("code", &permCodes).Error
			}
			if len(permCodes) == 0 {
				permCodes = []string{
					"distribution:site_view",
					"distribution:rule_view",
					"distribution:order_view",
					"distribution:account_view",
					"distribution:account_display",
					"distribution:payment_view",
					"distribution:payment_manage",
					"distribution:settlement_view",
					"distribution:settlement_manage",
				}
			}
			raw, _ := json.Marshal(permCodes)
			_ = r.redis.Set(ctx, fmt.Sprintf("admin:perms:%d", admin.ID), string(raw), 2*time.Hour).Err()
		}
	}

	return &admin, &dto, nil
}

func (r *Repository) GetMemberProfile(ctx context.Context, adminID uint64) (*DistributionCurrentMemberDTO, error) {
	if r.db == nil {
		return nil, ErrDependencyUnavailable
	}
	var admin model.AdminUser
	if err := r.db.WithContext(ctx).First(&admin, adminID).Error; err != nil {
		return nil, err
	}
	var members []model.DistributionSiteMember
	if err := r.db.WithContext(ctx).Where("admin_user_id = ? AND status = 'active'", adminID).Find(&members).Error; err != nil {
		return nil, err
	}
	dto := DistributionCurrentMemberDTO{
		AdminID:      admin.ID,
		Username:     admin.Username,
		Nickname:     admin.Nickname,
		IsSuperadmin: len(members) == 0,
	}
	if len(members) > 0 {
		var site model.DistributionSite
		if err := r.db.WithContext(ctx).First(&site, members[0].SiteID).Error; err == nil {
			dto.SiteID = &site.ID
			dto.SiteCode = site.SiteCode
			dto.SiteName = site.SiteName
			dto.Domain = site.Domain
			dto.MemberType = members[0].MemberType
		}
	}
	return &dto, nil
}

func (r *Repository) OnboardSite(ctx context.Context, req OnboardSiteRequest) (*OnboardSiteResponse, error) {
	if r.db == nil {
		return nil, ErrDependencyUnavailable
	}
	var count int64
	if err := r.db.WithContext(ctx).Model(&model.DistributionSite{}).
		Where("site_code = ? OR domain = ?", req.SiteCode, req.Domain).Count(&count).Error; err != nil {
		return nil, err
	}
	if count > 0 {
		return nil, ErrDuplicateSiteCodeOrDomain
	}
	if err := r.db.WithContext(ctx).Model(&model.AdminUser{}).
		Where("username = ?", req.AdminUsername).Count(&count).Error; err != nil {
		return nil, err
	}
	if count > 0 {
		return nil, ErrDuplicateUsername
	}

	hash, err := bcrypt.GenerateFromPassword([]byte(req.AdminPassword), bcrypt.DefaultCost)
	if err != nil {
		return nil, err
	}

	var resp OnboardSiteResponse
	err = r.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
		displayEnabled := true
		if req.DisplayAccountEnabled != nil {
			displayEnabled = *req.DisplayAccountEnabled
		}
		taxEnabled := false
		if req.TaxEnabled != nil {
			taxEnabled = *req.TaxEnabled
		}
		taxRate := int64(100)
		if req.TaxRateBPS != nil {
			taxRate = *req.TaxRateBPS
		}

		site := model.DistributionSite{
			SiteCode:              req.SiteCode,
			SiteName:              req.SiteName,
			Domain:                req.Domain,
			Status:                "active",
			DisplayAccountEnabled: displayEnabled,
			TaxEnabled:            taxEnabled,
			TaxRateBPS:            taxRate,
		}
		if err := tx.Create(&site).Error; err != nil {
			return err
		}

		nickname := req.AdminNickname
		if nickname == "" {
			nickname = req.SiteName + "管理员"
		}
		adminUser := model.AdminUser{
			Username:           req.AdminUsername,
			PasswordHash:       string(hash),
			Nickname:           nickname,
			Status:             "active",
			TokenVersion:       1,
			PasswordMustChange: false,
		}
		if err := tx.Create(&adminUser).Error; err != nil {
			return err
		}

		var roleID uint64
		if err := tx.Table("roles").Where("code = ?", "ops").Pluck("id", &roleID).Error; err == nil && roleID > 0 {
			_ = tx.Exec("INSERT IGNORE INTO admin_user_roles (admin_user_id, role_id) VALUES (?, ?)", adminUser.ID, roleID).Error
		}

		memberType := req.MemberType
		if memberType == "" {
			memberType = "operator"
		}
		member := model.DistributionSiteMember{
			SiteID:      site.ID,
			AdminUserID: adminUser.ID,
			MemberType:  memberType,
			Status:      "active",
			DataScope:   "site",
		}
		if err := tx.Create(&member).Error; err != nil {
			return err
		}

		distReceive := req.DistributorReceiveRatio
		if distReceive == 0 {
			distReceive = 3.5
		}
		platSell := req.PlatformSellRatio
		if platSell == 0 {
			platSell = 4.0
		}
		serviceFee := req.ServiceFeeValue
		if serviceFee == 0 {
			serviceFee = 2.5
		}

		rule := model.DistributionRuleVersion{
			SiteID:                  &site.ID,
			Mode:                    ModeTwoPartyDistributorReceive,
			Version:                 1,
			Status:                  "active",
			DistributorReceiveRatio: distReceive,
			PlatformSellRatio:       platSell,
			ServiceFeeValue:         serviceFee,
			ServiceFeeUnit:          ServiceFeeUnitFixedAmount,
			PaymentFeeBPS:           50,
			TaxEnabled:              taxEnabled,
			TaxRateBPS:              taxRate,
			EffectiveFrom:           time.Now(),
		}
		if err := tx.Create(&rule).Error; err != nil {
			return err
		}

		resp = OnboardSiteResponse{
			Site: siteDTO(site),
			Rule: ruleDTO(rule),
			Member: DistributionCurrentMemberDTO{
				AdminID:      adminUser.ID,
				Username:     adminUser.Username,
				Nickname:     adminUser.Nickname,
				IsSuperadmin: false,
				SiteID:       &site.ID,
				SiteCode:     site.SiteCode,
				SiteName:     site.SiteName,
				Domain:       site.Domain,
				MemberType:   member.MemberType,
			},
		}
		return nil
	})
	if err != nil {
		return nil, err
	}
	return &resp, nil
}