Files
notarius/internal/modules/dnd/shared/source_ref_order.go

96 lines
2.7 KiB
Go

package shared
import (
"sort"
"gitea.maximumdirect.net/eric/notarius/internal/core/source"
)
// SourceRefOrder provides a stable snapshot of a source document's unit
// ordering for source-reference comparison and canonicalization.
type SourceRefOrder struct {
sourceID string
index source.DocumentIndex
}
// NewSourceRefOrder captures the source identity and unit positions from doc.
func NewSourceRefOrder(doc *source.SourceDocument) SourceRefOrder {
if doc == nil {
return SourceRefOrder{}
}
return SourceRefOrder{sourceID: doc.ID, index: source.NewDocumentIndex(doc)}
}
// Less orders references by source identity, then document positions when
// available, and finally literal endpoint IDs.
func (o SourceRefOrder) Less(left, right source.SourceRef) bool {
if left.SourceID != right.SourceID {
return left.SourceID < right.SourceID
}
if o.lessEndpoint(left.SourceID, left.StartUnitID, right.StartUnitID) {
return true
}
if o.lessEndpoint(left.SourceID, right.StartUnitID, left.StartUnitID) {
return false
}
return o.lessEndpoint(left.SourceID, left.EndUnitID, right.EndUnitID)
}
// EarliestValid returns the earliest document position among valid refs.
func (o SourceRefOrder) EarliestValid(refs []source.SourceRef) (int, bool) {
if len(refs) == 0 || o.sourceID == "" {
return 0, false
}
found := false
earliest := 0
for _, ref := range refs {
if o.index.ValidateRef(ref) != nil {
continue
}
start, _ := o.index.Position(ref.StartUnitID)
if !found || start < earliest {
earliest = start
found = true
}
}
return earliest, found
}
// Canonicalize returns an owned, stable-sorted, exactly de-duplicated copy of
// refs. It deliberately preserves invalid references for diagnostics.
func (o SourceRefOrder) Canonicalize(refs []source.SourceRef) []source.SourceRef {
if refs == nil {
return nil
}
canonical := append([]source.SourceRef{}, refs...)
sort.SliceStable(canonical, func(left, right int) bool {
return o.Less(canonical[left], canonical[right])
})
unique := make([]source.SourceRef, 0, len(canonical))
for _, ref := range canonical {
if len(unique) == 0 || unique[len(unique)-1] != ref {
unique = append(unique, ref)
}
}
return unique
}
func (o SourceRefOrder) lessEndpoint(sourceID string, left, right int) bool {
leftPosition, leftOK := o.position(sourceID, left)
rightPosition, rightOK := o.position(sourceID, right)
if leftOK != rightOK {
return leftOK
}
if leftOK && leftPosition != rightPosition {
return leftPosition < rightPosition
}
return left < right
}
func (o SourceRefOrder) position(sourceID string, unitID int) (int, bool) {
if o.sourceID == "" || sourceID != o.sourceID {
return 0, false
}
return o.index.Position(unitID)
}