package refund

import (
	"context"
	"strconv"

	"gorm.io/gorm"

	"github.com/break/junhong_cmp_fiber/internal/infrastructure/audit"
	"github.com/break/junhong_cmp_fiber/internal/model"
	"github.com/break/junhong_cmp_fiber/pkg/constants"
	"github.com/break/junhong_cmp_fiber/pkg/errors"
)

// appendRefundAudit 在调用方事务内追加退款状态及完整关联资源。
func (s *Service) appendRefundAudit(
	ctx context.Context,
	tx *gorm.DB,
	refundID uint,
	actionCode string,
	summary string,
	eventID string,
	beforeRefund map[string]any,
	beforeOrder map[string]any,
	subjectSummary string,
) error {
	if s.auditWriter == nil {
		return errors.New(errors.CodeInvalidStatus, "退款统一审计接缝未配置")
	}
	var refund model.RefundRequest
	if err := tx.WithContext(ctx).First(&refund, refundID).Error; err != nil {
		return errors.Wrap(errors.CodeDatabaseError, err, "查询退款审计快照失败")
	}
	var order model.Order
	if err := tx.WithContext(ctx).First(&order, refund.OrderID).Error; err != nil {
		return errors.Wrap(errors.CodeDatabaseError, err, "查询退款关联订单审计快照失败")
	}

	primary := audit.RefundResource(&refund, constants.AuditResourceRelationPrimary, constants.AuditResourceRoleRefundTarget)
	primary.BeforeData = beforeRefund
	primary.AfterData = refundAuditState(&refund)
	primary.SubjectVisibility = constants.AuditSubjectResult
	primary.SubjectSummary = subjectSummary
	orderResource := audit.OrderResource(&order, constants.AuditResourceRelationReference, constants.AuditResourceRoleRefundOrder)
	orderResource.BeforeData = beforeOrder
	orderResource.AfterData = map[string]any{"payment_status": order.PaymentStatus}
	orderResource.SubjectVisibility = constants.AuditSubjectInternalOnly
	resources := []audit.ResourceInput{primary, orderResource}

	if refund.ApprovalInstanceID != nil {
		var approval model.ApprovalInstance
		if err := tx.WithContext(ctx).First(&approval, *refund.ApprovalInstanceID).Error; err != nil {
			return errors.Wrap(errors.CodeDatabaseError, err, "查询退款审批审计快照失败")
		}
		resource := audit.ApprovalInstanceResource(&approval, constants.AuditResourceRelationReference, constants.AuditResourceRoleRefundApproval, nil, nil)
		resource.SubjectVisibility = constants.AuditSubjectInternalOnly
		resources = append(resources, resource)
	}
	asset, err := audit.RefundAssetResource(ctx, tx, &order, subjectSummary)
	if err != nil {
		return err
	}
	if asset != nil {
		resources = append(resources, *asset)
	}
	if actionCode == constants.AuditActionRefundApproved || actionCode == constants.AuditActionRefundAssetProcessed {
		chain, err := refundChainAuditResources(ctx, tx, &refund, &order)
		if err != nil {
			return err
		}
		resources = append(resources, chain...)
	}

	return s.auditWriter.Append(ctx, tx, audit.AppendInput{
		EventID: eventID, ActionCode: actionCode, Summary: summary,
		ScopeType: constants.AuditScopePlatform, Result: constants.AuditResultSuccess,
		CorrelationID: refund.RefundNo,
		Metadata: map[string]any{
			"requested_refund_amount": refund.RequestedRefundAmount,
			"approved_refund_amount":  refund.ApprovedRefundAmount,
		},
		Resources: resources,
	})
}

// refundChainAuditResources 汇总退款已形成的资金、佣金、套餐和通知事实引用。
func refundChainAuditResources(ctx context.Context, tx *gorm.DB, refund *model.RefundRequest, order *model.Order) ([]audit.ResourceInput, error) {
	resources, err := refundFinanceAuditResources(ctx, tx, refund, order)
	if err != nil {
		return nil, err
	}
	var commissions []model.CommissionRecord
	if err := tx.WithContext(ctx).Where("order_id = ?", order.ID).Order("id ASC").Find(&commissions).Error; err != nil {
		return nil, errors.Wrap(errors.CodeDatabaseError, err, "查询退款佣金审计快照失败")
	}
	for i := range commissions {
		resource := audit.CommissionRecordResource(&commissions[i], nil, nil)
		resource.Relation = constants.AuditResourceRelationReference
		resource.SubjectVisibility = constants.AuditSubjectInternalOnly
		resources = append(resources, resource)
	}
	var usages []model.PackageUsage
	if err := tx.WithContext(ctx).Where("refund_id = ?", refund.ID).Order("id ASC").Find(&usages).Error; err != nil {
		return nil, errors.Wrap(errors.CodeDatabaseError, err, "查询退款套餐权益审计快照失败")
	}
	for i := range usages {
		resource := audit.PackageUsageResource(&usages[i], constants.AuditResourceRelationReference, constants.AuditResourceRoleRefundPackageUsage, nil, nil)
		resource.SubjectVisibility = constants.AuditSubjectInternalOnly
		resources = append(resources, resource)
	}
	var notification model.OutboxEvent
	notificationEventID := "refund:" + strconv.FormatUint(uint64(refund.ID), 10) + ":completed"
	if err := tx.WithContext(ctx).Where("event_id = ?", notificationEventID).First(&notification).Error; err == nil {
		id := strconv.FormatUint(uint64(notification.ID), 10)
		resources = append(resources, audit.ResourceInput{
			Type: constants.AuditResourceOutboxEvent, ID: &id, Key: notification.EventID, DisplayName: notification.EventID,
			Relation: constants.AuditResourceRelationReference, Role: constants.AuditResourceRoleRefundNotification,
			IdentitySnapshot: map[string]any{
				"event_id": notification.EventID, "event_type": notification.EventType,
				"aggregate_type": notification.AggregateType, "aggregate_id": notification.AggregateID,
				"resource_type": notification.ResourceType, "resource_id": notification.ResourceID,
				"business_key": notification.BusinessKey,
			},
			SubjectVisibility: constants.AuditSubjectInternalOnly,
		})
	} else if err != gorm.ErrRecordNotFound {
		return nil, errors.Wrap(errors.CodeDatabaseError, err, "查询退款通知审计快照失败")
	}
	return resources, nil
}

// refundFinanceAuditResources 关联原扣款与退款流水，但不替代钱包流水权威事实。
func refundFinanceAuditResources(ctx context.Context, tx *gorm.DB, refund *model.RefundRequest, order *model.Order) ([]audit.ResourceInput, error) {
	var agentTransactions []model.AgentWalletTransaction
	if err := tx.WithContext(ctx).Unscoped().
		Where("(reference_type = ? AND reference_id = ? AND transaction_type = ? AND status = ?) OR (reference_type = ? AND reference_id = ? AND transaction_type = ? AND status = ?)",
			constants.ReferenceTypeOrder, order.ID, constants.AgentTransactionTypeDeduct, constants.TransactionStatusSuccess,
			constants.ReferenceTypeRefund, refund.ID, constants.AgentTransactionTypeRefund, constants.TransactionStatusSuccess).
		Order("id DESC").Find(&agentTransactions).Error; err != nil {
		return nil, errors.Wrap(errors.CodeDatabaseError, err, "查询退款代理钱包流水审计快照失败")
	}
	resources := make([]audit.ResourceInput, 0, len(agentTransactions)*2+2)
	wallets := make(map[uint]struct{}, len(agentTransactions))
	for i := range agentTransactions {
		transaction := &agentTransactions[i]
		if _, exists := wallets[transaction.AgentWalletID]; !exists {
			var wallet model.AgentWallet
			if err := tx.WithContext(ctx).First(&wallet, transaction.AgentWalletID).Error; err != nil {
				return nil, errors.Wrap(errors.CodeDatabaseError, err, "查询退款代理钱包审计快照失败")
			}
			resources = append(resources, agentWalletRefundResource(&wallet, transaction))
			wallets[transaction.AgentWalletID] = struct{}{}
		}
		resources = append(resources, agentWalletRefundTransactionResource(transaction, refund.ID))
	}

	var assetTransactions []model.AssetWalletTransaction
	if err := tx.WithContext(ctx).Unscoped().
		Where("(reference_type = ? AND reference_no = ? AND transaction_type = ? AND status = ?) OR (reference_type = ? AND reference_no = ? AND transaction_type = ? AND status = ?)",
			constants.ReferenceTypeOrder, order.OrderNo, constants.AssetTransactionTypeDeduct, constants.TransactionStatusSuccess,
			constants.ReferenceTypeRefund, refund.RefundNo, constants.AssetTransactionTypeRefund, constants.TransactionStatusSuccess).
		Order("id DESC").Find(&assetTransactions).Error; err != nil {
		return nil, errors.Wrap(errors.CodeDatabaseError, err, "查询退款资产钱包流水审计快照失败")
	}
	assetWallets := make(map[uint]struct{}, len(assetTransactions))
	for i := range assetTransactions {
		transaction := &assetTransactions[i]
		if _, exists := assetWallets[transaction.AssetWalletID]; !exists {
			var wallet model.AssetWallet
			if err := tx.WithContext(ctx).First(&wallet, transaction.AssetWalletID).Error; err != nil {
				return nil, errors.Wrap(errors.CodeDatabaseError, err, "查询退款资产钱包审计快照失败")
			}
			resources = append(resources, assetWalletRefundResource(&wallet, transaction))
			assetWallets[transaction.AssetWalletID] = struct{}{}
		}
		resources = append(resources, assetWalletRefundTransactionResource(transaction, refund.RefundNo))
	}
	return resources, nil
}

// agentWalletRefundResource 构造代理钱包退款余额变化资源。
func agentWalletRefundResource(wallet *model.AgentWallet, transaction *model.AgentWalletTransaction) audit.ResourceInput {
	id := strconv.FormatUint(uint64(wallet.ID), 10)
	return audit.ResourceInput{
		Type: constants.AuditResourceAgentWallet, ID: &id, Key: id, DisplayName: "代理钱包 " + id,
		Relation: constants.AuditResourceRelationAffected, Role: constants.AuditResourceRoleRefundWallet,
		IdentitySnapshot: map[string]any{
			"id": wallet.ID, "shop_id": wallet.ShopID, "wallet_type": wallet.WalletType,
			"currency": wallet.Currency, "status": wallet.Status,
		},
		BeforeData: map[string]any{"balance": transaction.BalanceBefore},
		AfterData:  map[string]any{"balance": transaction.BalanceAfter}, SubjectVisibility: constants.AuditSubjectInternalOnly,
	}
}

// agentWalletRefundTransactionResource 区分原扣款流水和退款回充流水。
func agentWalletRefundTransactionResource(transaction *model.AgentWalletTransaction, refundID uint) audit.ResourceInput {
	id := strconv.FormatUint(uint64(transaction.ID), 10)
	role := constants.AuditResourceRoleRefundOriginalTransaction
	relation := constants.AuditResourceRelationReference
	if transaction.ReferenceType != nil && *transaction.ReferenceType == constants.ReferenceTypeRefund &&
		transaction.ReferenceID != nil && *transaction.ReferenceID == refundID {
		role, relation = constants.AuditResourceRoleRefundTransaction, constants.AuditResourceRelationAffected
	}
	return audit.ResourceInput{
		Type: constants.AuditResourceAgentWalletTransaction, ID: &id, Key: id, DisplayName: "代理钱包流水 " + id,
		Relation: relation, Role: role,
		IdentitySnapshot: map[string]any{
			"id": transaction.ID, "agent_wallet_id": transaction.AgentWalletID, "shop_id": transaction.ShopID,
			"transaction_type": transaction.TransactionType, "transaction_subtype": transaction.TransactionSubtype,
			"reference_type": transaction.ReferenceType, "reference_id": transaction.ReferenceID, "status": transaction.Status,
		},
		AfterData: map[string]any{
			"amount": transaction.Amount, "balance_before": transaction.BalanceBefore, "balance_after": transaction.BalanceAfter,
		},
		SubjectVisibility: constants.AuditSubjectInternalOnly,
	}
}

// assetWalletRefundResource 构造资产钱包退款余额变化资源。
func assetWalletRefundResource(wallet *model.AssetWallet, transaction *model.AssetWalletTransaction) audit.ResourceInput {
	id := strconv.FormatUint(uint64(wallet.ID), 10)
	return audit.ResourceInput{
		Type: constants.AuditResourceAssetWallet, ID: &id, Key: id, DisplayName: "资产钱包 " + id,
		Relation: constants.AuditResourceRelationAffected, Role: constants.AuditResourceRoleRefundWallet,
		IdentitySnapshot: map[string]any{
			"id": wallet.ID, "resource_type": wallet.ResourceType, "resource_id": wallet.ResourceID,
			"currency": wallet.Currency, "shop_id_tag": wallet.ShopIDTag, "enterprise_id_tag": wallet.EnterpriseIDTag,
		},
		BeforeData: map[string]any{"balance": transaction.BalanceBefore},
		AfterData:  map[string]any{"balance": transaction.BalanceAfter}, SubjectVisibility: constants.AuditSubjectInternalOnly,
	}
}

// assetWalletRefundTransactionResource 区分资产钱包原扣款流水和退款回充流水。
func assetWalletRefundTransactionResource(transaction *model.AssetWalletTransaction, refundNo string) audit.ResourceInput {
	id := strconv.FormatUint(uint64(transaction.ID), 10)
	role := constants.AuditResourceRoleRefundOriginalTransaction
	relation := constants.AuditResourceRelationReference
	if transaction.ReferenceType != nil && *transaction.ReferenceType == constants.ReferenceTypeRefund &&
		transaction.ReferenceNo != nil && *transaction.ReferenceNo == refundNo {
		role, relation = constants.AuditResourceRoleRefundTransaction, constants.AuditResourceRelationAffected
	}
	return audit.ResourceInput{
		Type: constants.AuditResourceAssetWalletTransaction, ID: &id, Key: id, DisplayName: "资产钱包流水 " + id,
		Relation: relation, Role: role,
		IdentitySnapshot: map[string]any{
			"id": transaction.ID, "asset_wallet_id": transaction.AssetWalletID,
			"resource_type": transaction.ResourceType, "resource_id": transaction.ResourceID,
			"transaction_type": transaction.TransactionType, "reference_type": transaction.ReferenceType,
			"reference_no": transaction.ReferenceNo, "status": transaction.Status,
		},
		AfterData: map[string]any{
			"amount": transaction.Amount, "balance_before": transaction.BalanceBefore, "balance_after": transaction.BalanceAfter,
		},
		SubjectVisibility: constants.AuditSubjectInternalOnly,
	}
}

// appendCommissionAudit 将佣金失效、钱包扣减和回扣流水绑定在同一事务。
func (s *Service) appendCommissionAudit(ctx context.Context, tx *gorm.DB, refund *model.RefundRequest, commission *model.CommissionRecord, wallet *model.AgentWallet, transaction *model.AgentWalletTransaction) error {
	if s.auditWriter == nil {
		return errors.New(errors.CodeInvalidStatus, "退款统一审计接缝未配置")
	}
	primary := audit.RefundResource(refund, constants.AuditResourceRelationPrimary, constants.AuditResourceRoleRefundTarget)
	primary.SubjectVisibility = constants.AuditSubjectResult
	primary.SubjectSummary = "退款佣金已处理"
	commissionResource := audit.CommissionRecordResource(commission,
		map[string]any{"status": constants.CommissionStatusReleased}, map[string]any{"status": constants.CommissionStatusInvalid})
	commissionResource.SubjectVisibility = constants.AuditSubjectInternalOnly
	transactionResource := agentWalletRefundTransactionResource(transaction, refund.ID)
	transactionResource.Relation = constants.AuditResourceRelationAffected
	transactionResource.Role = constants.AuditResourceRoleRefundTransaction
	resources := []audit.ResourceInput{primary, commissionResource, agentWalletRefundResource(wallet, transaction), transactionResource}
	var order model.Order
	if err := tx.WithContext(ctx).First(&order, refund.OrderID).Error; err != nil {
		return errors.Wrap(errors.CodeDatabaseError, err, "查询退款佣金关联订单审计快照失败")
	}
	orderResource := audit.OrderResource(&order, constants.AuditResourceRelationReference, constants.AuditResourceRoleRefundOrder)
	orderResource.SubjectVisibility = constants.AuditSubjectInternalOnly
	resources = append(resources, orderResource)
	var shop model.Shop
	if err := tx.WithContext(ctx).First(&shop, commission.ShopID).Error; err != nil {
		return errors.Wrap(errors.CodeDatabaseError, err, "查询退款佣金关联店铺审计快照失败")
	}
	shopResource := audit.ShopResource(&shop, constants.AuditResourceRelationReference, constants.AuditResourceRoleRefundCommission)
	shopResource.SubjectVisibility = constants.AuditSubjectInternalOnly
	resources = append(resources, shopResource)
	return s.auditWriter.Append(ctx, tx, audit.AppendInput{
		EventID:    "refund:" + strconv.FormatUint(uint64(refund.ID), 10) + ":commission:" + strconv.FormatUint(uint64(commission.ID), 10) + ":invalidated",
		ActionCode: constants.AuditActionRefundCommissionInvalidated, Summary: "退款失效佣金",
		ScopeType: constants.AuditScopePlatform, Result: constants.AuditResultSuccess,
		CorrelationID: refund.RefundNo, Resources: resources,
	})
}

// recordRefundFailure 在原业务事务回滚后记录已定位退款的失败或拒绝。
func (s *Service) recordRefundFailure(ctx context.Context, actionCode, summary string, refund *model.RefundRequest, order *model.Order, businessErr error) {
	if businessErr == nil || refund == nil || refund.RefundNo == "" || s.auditWriter == nil || s.db == nil {
		return
	}
	primary := audit.RefundResource(refund, constants.AuditResourceRelationPrimary, constants.AuditResourceRoleRefundTarget)
	primary.BeforeData = refundAuditState(refund)
	primary.SubjectVisibility = constants.AuditSubjectInternalOnly
	resources := []audit.ResourceInput{primary}
	if order != nil && (order.ID > 0 || order.OrderNo != "") {
		resource := audit.OrderResource(order, constants.AuditResourceRelationReference, constants.AuditResourceRoleRefundOrder)
		resource.SubjectVisibility = constants.AuditSubjectInternalOnly
		resources = append(resources, resource)
	}
	s.auditWriter.RecordFailure(ctx, s.db, audit.AppendInput{
		ActionCode: actionCode, Summary: summary, ScopeType: constants.AuditScopePlatform,
		CorrelationID: refund.RefundNo, Resources: resources,
	}, businessErr)
}

// recordCommissionFailure 在单条佣金回扣事务回滚后记录失败事实。
func (s *Service) recordCommissionFailure(ctx context.Context, refund *model.RefundRequest, commission *model.CommissionRecord, businessErr error) {
	if businessErr == nil || refund == nil || commission == nil || s.auditWriter == nil || s.db == nil {
		return
	}
	primary := audit.RefundResource(refund, constants.AuditResourceRelationPrimary, constants.AuditResourceRoleRefundTarget)
	primary.SubjectVisibility = constants.AuditSubjectInternalOnly
	commissionResource := audit.CommissionRecordResource(commission, map[string]any{"status": commission.Status}, nil)
	commissionResource.SubjectVisibility = constants.AuditSubjectInternalOnly
	s.auditWriter.RecordFailure(ctx, s.db, audit.AppendInput{
		ActionCode: constants.AuditActionRefundCommissionInvalidated, Summary: "退款失效佣金失败",
		ScopeType: constants.AuditScopePlatform, CorrelationID: refund.RefundNo,
		Resources: []audit.ResourceInput{primary, commissionResource},
	}, businessErr)
}

func refundAuditState(refund *model.RefundRequest) map[string]any {
	return map[string]any{
		"status": refund.Status, "approved_refund_amount": refund.ApprovedRefundAmount,
		"approval_instance_id": refund.ApprovalInstanceID, "processor_id": refund.ProcessorID,
		"processed_at": refund.ProcessedAt, "commission_deducted": refund.CommissionDeducted,
		"asset_reset": refund.AssetReset, "reject_reason": refund.RejectReason, "remark": refund.Remark,
	}
}

// markRefundAssetProcessed 仅在首次完成后处理时同事务写入完成标记和审计事件。
func (s *Service) markRefundAssetProcessed(ctx context.Context, refundID uint) error {
	return s.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
		result := tx.WithContext(ctx).Model(&model.RefundRequest{}).
			Where("id = ? AND asset_reset = ?", refundID, false).Update("asset_reset", true)
		if result.Error != nil {
			return errors.Wrap(errors.CodeDatabaseError, result.Error, "更新退款资产处理标记失败")
		}
		if result.RowsAffected == 0 {
			return nil
		}
		return s.appendRefundAudit(ctx, tx, refundID, constants.AuditActionRefundAssetProcessed, "完成退款资产后处理",
			"refund:"+strconv.FormatUint(uint64(refundID), 10)+":asset-processed",
			map[string]any{"asset_reset": false}, nil, "退款资产处理已完成")
	})
}