Feat/undo redo

internal/jsonx/node.go

@@ -37,6 +37,16 @@ type Node struct {
 	LineNumber      int
 }
 
+type Tombstone struct {
+	Target   *Node
+	Parent   *Node
+	Prev     *Node
+	Next     *Node
+	EndOf    *Node
+	Index    int
+	HadComma bool
+}
+
 // Append ands a node as a child to the current node (body of {...} or [...]).
 func (n *Node) Append(child *Node) {
 	if n.End == nil {
@@ -367,3 +377,87 @@ func (n *Node) ForEach(cb func(*Node)) {
 		}
 	}
 }
+
+func (n *Node) GetNodeToDelete() (*Node, bool) {
+	if n == nil {
+		return nil, false
+	}
+	// Avoid closing bracket nodes (Index == -1 used for brackets)
+	if n.Index == -1 {
+		return nil, false
+	}
+	parent := n.Parent
+	if parent == nil { // avoid deleting root
+		return nil, false
+	}
+	// If current points to a wrap placeholder, move to its parent value
+	node := n
+	if n.Chunk != "" && n.Value == "" && n.Parent != nil {
+		node = node.Parent
+		parent = node.Parent
+		if parent == nil {
+			return nil, false
+		}
+	}
+	return node, true
+}
+
+func (n *Node) CreateTombstone() Tombstone {
+	endOf := n
+	if n.End != nil {
+		endOf = n.End
+	} else if n.ChunkEnd != nil {
+		endOf = n.ChunkEnd
+	}
+
+	t := Tombstone{
+		Target: n,
+		EndOf:  endOf,
+		Parent: n.Parent,
+		Prev:   n.Prev,
+		Next:   endOf.Next,
+		Index:  n.Index,
+	}
+
+	if t.Prev != nil && t.Prev != t.Parent {
+		t.HadComma = t.Prev.Comma
+	}
+
+	return t
+}
+
+func (t *Tombstone) DoUndo() {
+	if t.Prev != nil {
+		t.Prev.Next = t.Target
+	}
+	if t.Next != nil {
+		t.Next.Prev = t.EndOf
+	}
+
+	// if it was the first child
+	if t.Parent != nil && t.Parent.Next == t.Next {
+		t.Parent.Next = t.Target
+	}
+
+	// if DeleteNode cleared a comma
+	if t.Prev != nil && t.Prev != t.Parent {
+		t.Prev.Comma = t.HadComma
+	}
+
+	// Reverse Array/Size logic
+	if t.Parent != nil {
+		t.Parent.Size++
+		if t.Parent.Kind == Array {
+			for it := t.Next; it != nil && it != t.Parent.End; {
+				if it.Parent == t.Parent && it.Index >= 0 {
+					it.Index++
+				}
+				if it.HasChildren() {
+					it = it.End.Next
+				} else {
+					it = it.Next
+				}
+			}
+		}
+	}
+}

keymap.go

@@ -30,6 +30,8 @@ type KeyMap struct {
 	Preview             key.Binding `category:"Actions"`
 	Print               key.Binding `category:"Actions"`
 	Open                key.Binding `category:"Actions"`
+	Undo                key.Binding `category:"Actions"`
+	Redo                key.Binding `category:"Actions"`
 	ToggleWrap          key.Binding `category:"View"`
 	ShowSelector        key.Binding `category:"View"`
 	GoBack              key.Binding `category:"Navigation"`
@@ -148,6 +150,14 @@ func init() {
 			key.WithKeys("d"),
 			key.WithHelp("", "delete node"),
 		),
+		Undo: key.NewBinding(
+			key.WithKeys("u"),
+			key.WithHelp("", "undo delete"),
+		),
+		Redo: key.NewBinding(
+			key.WithKeys("ctrl+r"),
+			key.WithHelp("", "redo delete"),
+		),
 		CommandLine: key.NewBinding(
 			key.WithKeys(":"),
 			key.WithHelp("", "open command line"),

main.go

@@ -360,6 +360,8 @@ type model struct {
 	printErrorOnExit      error
 	spinner               spinner.Model
 	locationHistory       []location
+	undoStack             []Tombstone
+	redoStack             []Tombstone
 	locationIndex         int // position in locationHistory
 	keysIndex             []string
 	keysIndexNodes        []*Node
@@ -976,7 +978,12 @@ func (m *model) handleKey(msg tea.KeyMsg) (tea.Model, tea.Cmd) {
 
 	case key.Matches(msg, keyMap.Delete):
 		m.deletePending = true
+	case key.Matches(msg, keyMap.Undo):
+		m.undoDelete()
+	case key.Matches(msg, keyMap.Redo): // Make sure Redo is defined in your keyMap
+		m.redoDelete()
 	}
+
 	return m, nil
 }
 
@@ -1035,6 +1042,46 @@ func (m *model) recordHistory() {
 	m.locationIndex = len(m.locationHistory)
 }
 
+func (m *model) recordDeleteHistory(ts Tombstone) {
+	m.undoStack = append(m.undoStack, ts)
+	m.redoStack = []Tombstone{}
+
+	if len(m.undoStack) > 100 {
+		m.undoStack = m.undoStack[1:]
+	}
+}
+
+func (m *model) undoDelete() {
+	if len(m.undoStack) == 0 {
+		return
+	}
+
+	lastIdx := len(m.undoStack) - 1
+	t := m.undoStack[lastIdx]
+	m.undoStack = m.undoStack[:lastIdx]
+
+	t.DoUndo()
+
+	m.redoStack = append(m.redoStack, t)
+	m.selectNode(t.Target)
+}
+
+func (m *model) redoDelete() {
+	if len(m.redoStack) == 0 {
+		return
+	}
+
+	t := m.redoStack[len(m.redoStack)-1]
+	m.redoStack = m.redoStack[:len(m.redoStack)-1]
+
+	if next, ok := DeleteNode(t.Target); ok {
+		m.selectNode(next)
+		m.recordHistory()
+	}
+
+	m.undoStack = append(m.undoStack, t)
+}
+
 func (m *model) scrollToBottom() {
 	if m.bottom == nil {
 		return
@@ -1467,7 +1514,16 @@ func (m *model) deleteAtCursor() {
 	if !ok || at == nil {
 		return
 	}
-	if next, ok := DeleteNode(at); ok {
+
+	nodeToDelete, ok := at.GetNodeToDelete()
+	if !ok {
+		return
+	}
+
+	ts := nodeToDelete.CreateTombstone()
+	m.recordDeleteHistory(ts)
+
+	if next, ok := DeleteNode(nodeToDelete); ok {
 		m.selectNode(next)
 		m.recordHistory()
 	}

main_test.go

@@ -115,3 +115,35 @@ func TestCollapseRecursiveWithSizes(t *testing.T) {
 	tm.Send(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("q")})
 	tm.WaitFinished(t, teatest.WithFinalTimeout(time.Second))
 }
+
+func TestUndoRedoInteraction(t *testing.T) {
+	tm := prepare(t)
+	targetKey := []byte(`"title"`)
+
+	// Leave root, then delete (first key)
+	tm.Send(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("j")})
+	tm.Send(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("d")})
+	tm.Send(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("d")})
+
+	// Verify the node is gone from the output
+	teatest.WaitFor(t, tm.Output(), func(b []byte) bool {
+		return !bytes.Contains(b, targetKey)
+	}, teatest.WithDuration(time.Second))
+
+	tm.Send(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("u")})
+
+	// Verify the node reappeared
+	teatest.WaitFor(t, tm.Output(), func(b []byte) bool {
+		return bytes.Contains(b, targetKey)
+	}, teatest.WithDuration(time.Second))
+
+	tm.Send(tea.KeyMsg{Type: tea.KeyCtrlR})
+
+	// Verify it is gone again
+	teatest.WaitFor(t, tm.Output(), func(b []byte) bool {
+		return !bytes.Contains(b, targetKey)
+	}, teatest.WithDuration(time.Second))
+
+	tm.Send(tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune("q")})
+	tm.WaitFinished(t)
+}

testdata/TestCollapseRecursive.golden

@@ -9,7 +9,8 @@
   "tags": […],
   "year": 3000,
   "funny": true,
-  "author": {"name":"John Doe",…}
+  "author": {"name":"John Doe",…},
+  "hasAvatar": true
 }
 ~
 ~
@@ -35,6 +36,5 @@
 ~
 ~
 ~
-~
 ~
                                                                              1% 

testdata/TestCollapseRecursiveWithSizes.golden

@@ -1,4 +1,4 @@
-[?25l[?2004h{ (6 keys)
+[?25l[?2004h{ (7 keys)
   "title": "Lorem ipsum",
   "text": "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusm
   od tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
@@ -9,7 +9,8 @@
   "tags": […], (3 items)
   "year": 3000,
   "funny": true,
-  "author": {"name":"John Doe",…} (2 keys)
+  "author": {"name":"John Doe",…}, (2 keys)
+  "hasAvatar": true
 }
 ~
 ~
@@ -35,6 +36,5 @@
 ~
 ~
 ~
-~
 ~
                                                                              1% 

testdata/TestDig.golden

@@ -0,0 +1,40 @@
+[?25l[?2004h{
+  "title": "Lorem ipsum",
+  "text": "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusm
+  od tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
+  , quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo cons
+  equat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum d
+  olore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident
+  , sunt in culpa qui officia deserunt mollit anim id est laborum.",
+  "tags": [
+    "lorem",
+    "ipsum",
+    null
+  ],
+  "year": 3000,
+  "funny": true,
+  "author": {
+    "name": "John Doe",
+    "email": "john@doe.com"
+  },
+  "hasAvatar": true
+}
+~
+~
+~
+~
+~
+~
+~
+~
+~
+~
+~
+~
+~
+~
+~
+~
+~
+~
+.year                                                                       56% 

testdata/TestGotoLine.golden

@@ -17,8 +17,9 @@
 11    "author": {
 12      "name": "John Doe",
 13      "email": "john@doe.com"
-14    }
-15  }
+14    },
+15    "hasAvatar": true
+16  }
 ~
 ~
 ~
@@ -36,5 +37,4 @@
 ~
 ~
 ~
-~
-.tags[0]                                                                    33% 
+.tags[0]                                                                    31% 

testdata/TestGotoLineCollapsed.golden

@@ -14,8 +14,9 @@
  8    ],
  9    "year": 3000,
 10    "funny": true,
-11    "author": {"name":"John Doe",…}
-15  }
+11    "author": {"name":"John Doe",…},
+15    "hasAvatar": true
+16  }
 ~
 ~
 ~
@@ -36,5 +37,4 @@
 ~
 ~
 ~
-~
-.tags[0]                                                                    33% 
+.tags[0]                                                                    31% 

testdata/TestGotoLineInputGreaterThanTotalLines.golden

@@ -17,9 +17,9 @@
 11    "author": {
 12      "name": "John Doe",
 13      "email": "john@doe.com"
-14    }
-15  }
-~
+14    },
+15    "hasAvatar": true
+16  }
 ~
 ~
 ~