Merge pull request #14 from chojs23/chore/refactor

chore : refactor

Author: chojs23

internal/engine/state.go

@@ -1,31 +1,20 @@
 package engine
 
 import (
-	"bytes"
 	"fmt"
 
 	"github.com/chojs23/ec/internal/markers"
 )
 
-// State manages resolution state for a conflict document with undo support.
+// State manages resolution state for a conflict document.
 type State struct {
-	doc         markers.Document
-	undoStack   []markers.Document
-	redoStack   []markers.Document
-	maxUndoSize int
+	doc markers.Document
 }
 
 // NewState creates a new State from a parsed document.
-// maxUndoSize controls how many undo operations to retain (must be >= 1).
-func NewState(doc markers.Document, maxUndoSize int) (*State, error) {
-	if maxUndoSize < 1 {
-		return nil, fmt.Errorf("maxUndoSize must be >= 1, got %d", maxUndoSize)
-	}
+func NewState(doc markers.Document) (*State, error) {
 	return &State{
-		doc:         doc,
-		undoStack:   make([]markers.Document, 0, maxUndoSize),
-		redoStack:   make([]markers.Document, 0, maxUndoSize),
-		maxUndoSize: maxUndoSize,
+		doc: doc,
 	}, nil
 }
 
@@ -54,9 +43,6 @@ func (s *State) ApplyResolution(conflictIndex int, resolution markers.Resolution
 		return nil
 	}
 
-	// Save current state to undo stack before modifying, and invalidate redo history.
-	s.beginMutation()
-
 	seg.Resolution = resolution
 	s.doc.Segments[ref.SegmentIndex] = seg
 
@@ -88,9 +74,6 @@ func (s *State) ApplyAll(resolution markers.Resolution) error {
 		return nil
 	}
 
-	// Save current state to undo stack before modifying, and invalidate redo history.
-	s.beginMutation()
-
 	for _, ref := range s.doc.Conflicts {
 		seg, ok := s.doc.Segments[ref.SegmentIndex].(markers.ConflictSegment)
 		if !ok {
@@ -103,55 +86,12 @@ func (s *State) ApplyAll(resolution markers.Resolution) error {
 	return nil
 }
 
-// Undo restores the previous state.
-// Returns error if no undo history is available.
-func (s *State) Undo() error {
-	if len(s.undoStack) == 0 {
-		return fmt.Errorf("no undo history available")
-	}
-
-	// Save current state to redo stack before restoring previous state.
-	s.pushWithLimit(&s.redoStack, s.doc)
-
-	// Pop the last state
-	lastIdx := len(s.undoStack) - 1
-	s.doc = s.undoStack[lastIdx]
-	s.undoStack = s.undoStack[:lastIdx]
-
-	return nil
-}
-
-// Redo reapplies a previously undone state.
-// Returns error if no redo history is available.
-func (s *State) Redo() error {
-	if len(s.redoStack) == 0 {
-		return fmt.Errorf("no redo history available")
-	}
-
-	// Save current state to undo stack before restoring redone state.
-	s.pushWithLimit(&s.undoStack, s.doc)
-
-	lastIdx := len(s.redoStack) - 1
-	s.doc = s.redoStack[lastIdx]
-	s.redoStack = s.redoStack[:lastIdx]
-
-	return nil
-}
-
-// ReplaceDocument replaces the current document as a single undoable mutation.
-// If the incoming document is identical to current state, no history is added.
+// ReplaceDocument replaces the current document.
 func (s *State) ReplaceDocument(doc markers.Document) {
-	if documentsEqual(s.doc, doc) {
+	if markers.DocumentsEqual(s.doc, doc) {
 		return
 	}
-	s.beginMutation()
-	s.doc = cloneDocument(doc)
-}
-
-// PushUndoPoint records the current state as an undo step.
-// Useful for undoable metadata changes outside Document.
-func (s *State) PushUndoPoint() {
-	s.beginMutation()
+	s.doc = markers.CloneDocument(doc)
 }
 
 // Preview generates the resolved output by concatenating segments with resolutions applied.
@@ -161,90 +101,6 @@ func (s *State) Preview() ([]byte, error) {
 	return markers.RenderResolved(s.doc)
 }
 
-// Document returns a copy of the current document state.
 func (s *State) Document() markers.Document {
-	return s.doc
-}
-
-// UndoDepth returns the current number of undo operations available.
-func (s *State) UndoDepth() int {
-	return len(s.undoStack)
-}
-
-// RedoDepth returns the current number of redo operations available.
-func (s *State) RedoDepth() int {
-	return len(s.redoStack)
-}
-
-// beginMutation saves the current state to undo and clears redo history.
-func (s *State) beginMutation() {
-	s.pushWithLimit(&s.undoStack, s.doc)
-	s.redoStack = s.redoStack[:0]
-}
-
-// pushWithLimit saves a document snapshot into the stack and enforces max size.
-func (s *State) pushWithLimit(stack *[]markers.Document, doc markers.Document) {
-	*stack = append(*stack, cloneDocument(doc))
-	if len(*stack) > s.maxUndoSize {
-		*stack = (*stack)[1:]
-	}
-}
-
-func cloneDocument(doc markers.Document) markers.Document {
-	// Deep copy the document to preserve state
-	docCopy := markers.Document{
-		Segments:  make([]markers.Segment, len(doc.Segments)),
-		Conflicts: make([]markers.ConflictRef, len(doc.Conflicts)),
-	}
-
-	for i, seg := range doc.Segments {
-		switch v := seg.(type) {
-		case markers.TextSegment:
-			// TextSegment.Bytes is immutable (we never modify it), so shallow copy is safe
-			docCopy.Segments[i] = v
-		case markers.ConflictSegment:
-			// ConflictSegment fields are immutable byte slices and Resolution enum, shallow copy is safe
-			docCopy.Segments[i] = v
-		}
-	}
-
-	copy(docCopy.Conflicts, doc.Conflicts)
-	return docCopy
-}
-
-func documentsEqual(left, right markers.Document) bool {
-	if len(left.Conflicts) != len(right.Conflicts) || len(left.Segments) != len(right.Segments) {
-		return false
-	}
-	for i := range left.Conflicts {
-		if left.Conflicts[i] != right.Conflicts[i] {
-			return false
-		}
-	}
-	for i := range left.Segments {
-		switch l := left.Segments[i].(type) {
-		case markers.TextSegment:
-			r, ok := right.Segments[i].(markers.TextSegment)
-			if !ok || !bytes.Equal(l.Bytes, r.Bytes) {
-				return false
-			}
-		case markers.ConflictSegment:
-			r, ok := right.Segments[i].(markers.ConflictSegment)
-			if !ok {
-				return false
-			}
-			if !bytes.Equal(l.Ours, r.Ours) || !bytes.Equal(l.Base, r.Base) || !bytes.Equal(l.Theirs, r.Theirs) {
-				return false
-			}
-			if l.OursLabel != r.OursLabel || l.BaseLabel != r.BaseLabel || l.TheirsLabel != r.TheirsLabel {
-				return false
-			}
-			if l.Resolution != r.Resolution {
-				return false
-			}
-		default:
-			return false
-		}
-	}
-	return true
+	return markers.CloneDocument(s.doc)
 }