Method getLineageSources

lineage.go:838–876

getLineageSources retrieves the available fund sources from shadow balances for allocation. Uses a single batch query to fetch all shadow balances instead of N individual queries. Parameters: - ctx context.Context: The context for the operation. - mappings []model.LineageMapping: The lineage mappin

(ctx context.Context, mappings []model.LineageMapping)

// - []LineageSource: The available fund sources.
// - error: An error if the sources could not be retrieved.
func (l *LedgerForge) getLineageSources(ctx context.Context, mappings []model.LineageMapping) ([]LineageSource, error) {
	if len(mappings) == 0 {
		return nil, nil
	}

	// Collect all shadow balance IDs for batch query
	shadowBalanceIDs := make([]string, 0, len(mappings))
	for _, mapping := range mappings {
		shadowBalanceIDs = append(shadowBalanceIDs, mapping.ShadowBalanceID)
	}

	// Fetch all shadow balances in a single query
	balances, err := l.datasource.GetBalancesByIDsLite(ctx, shadowBalanceIDs)
	if err != nil {
		return nil, fmt.Errorf("failed to fetch shadow balances: %w", err)
	}

	// Build sources from the fetched balances
	var sources []LineageSource
	for _, mapping := range mappings {
		balance, exists := balances[mapping.ShadowBalanceID]
		if !exists {
			continue
		}

		if balance.DebitBalance != nil && balance.CreditBalance != nil && balance.DebitBalance.Cmp(big.NewInt(0)) > 0 {
			available := new(big.Int).Sub(balance.DebitBalance, balance.CreditBalance)
			if available.Cmp(big.NewInt(0)) > 0 {
				sources = append(sources, LineageSource{
					BalanceID: mapping.ShadowBalanceID,
					Balance:   available,
					CreatedAt: mapping.CreatedAt,
				})
			}
		}
	}

	return sources, nil
}

// calculateAllocation calculates fund allocations based on the specified strategy.
// Supported strategies are FIFO, LIFO, and PROPORTIONAL.