Add insert command

internal/insert/summary.go

@@ -0,0 +1,84 @@
+package insert
+
+// Status represents the preview outcome for a candidate entry.
+type Status string
+
+const (
+	StatusChanged  Status = "changed"
+	StatusNoChange Status = "no_change"
+	StatusSkipped  Status = "skipped"
+)
+
+// PreviewEntry describes a single original → proposed mapping.
+type PreviewEntry struct {
+	OriginalPath string
+	ProposedPath string
+	Status       Status
+	InsertedText string
+}
+
+// Conflict captures a conflicting rename outcome.
+type Conflict struct {
+	OriginalPath string
+	ProposedPath string
+	Reason       string
+}
+
+// Summary aggregates counts, warnings, conflicts, and ledger metadata for insert operations.
+type Summary struct {
+	TotalCandidates int
+	TotalChanged    int
+	NoChange        int
+
+	Entries   []PreviewEntry
+	Conflicts []Conflict
+	Warnings  []string
+
+	LedgerMetadata map[string]any
+}
+
+// NewSummary constructs an empty summary with initialized maps.
+func NewSummary() *Summary {
+	return &Summary{
+		Entries:        make([]PreviewEntry, 0),
+		Conflicts:      make([]Conflict, 0),
+		Warnings:       make([]string, 0),
+		LedgerMetadata: make(map[string]any),
+	}
+}
+
+// RecordEntry appends a preview entry and updates aggregate counts.
+func (s *Summary) RecordEntry(entry PreviewEntry) {
+	s.Entries = append(s.Entries, entry)
+	s.TotalCandidates++
+
+	switch entry.Status {
+	case StatusChanged:
+		s.TotalChanged++
+	case StatusNoChange:
+		s.NoChange++
+	}
+}
+
+// AddConflict records a blocking conflict.
+func (s *Summary) AddConflict(conflict Conflict) {
+	s.Conflicts = append(s.Conflicts, conflict)
+}
+
+// AddWarning adds a warning if not already present.
+func (s *Summary) AddWarning(msg string) {
+	if msg == "" {
+		return
+	}
+	for _, existing := range s.Warnings {
+		if existing == msg {
+			return
+		}
+	}
+	s.Warnings = append(s.Warnings, msg)
+}
+
+// HasConflicts indicates whether apply should be blocked.
+func (s *Summary) HasConflicts() bool {
+	return len(s.Conflicts) > 0
+}