import (
"time"
+
+ dmp "github.com/sergi/go-diff/diffmatchpatch"
)
const (
EventType int
Text string
- Start int
- End int
+ Start Loc
+ End Loc
Time time.Time
}
// ExecuteTextEvent runs a text event
func ExecuteTextEvent(t *TextEvent, buf *Buffer) {
if t.EventType == TextEventInsert {
- buf.insert(t.Start, t.Text)
+ buf.insert(t.Start, []byte(t.Text))
} else if t.EventType == TextEventRemove {
t.Text = buf.remove(t.Start, t.End)
}
return eh
}
+// ApplyDiff takes a string and runs the necessary insertion and deletion events to make
+// the buffer equal to that string
+// This means that we can transform the buffer into any string and still preserve undo/redo
+// through insert and delete events
+func (eh *EventHandler) ApplyDiff(new string) {
+ differ := dmp.New()
+ diff := differ.DiffMain(eh.buf.String(), new, false)
+ loc := eh.buf.Start()
+ for _, d := range diff {
+ if d.Type == dmp.DiffDelete {
+ eh.Remove(loc, loc.Move(Count(d.Text), eh.buf))
+ } else {
+ if d.Type == dmp.DiffInsert {
+ eh.Insert(loc, d.Text)
+ }
+ loc = loc.Move(Count(d.Text), eh.buf)
+ }
+ }
+}
+
// Insert creates an insert text event and executes it
-func (eh *EventHandler) Insert(start int, text string) {
+func (eh *EventHandler) Insert(start Loc, text string) {
e := &TextEvent{
C: eh.buf.Cursor,
EventType: TextEventInsert,
Text: text,
Start: start,
- End: start + Count(text),
Time: time.Now(),
}
eh.Execute(e)
+ e.End = start.Move(Count(text), eh.buf)
}
// Remove creates a remove text event and executes it
-func (eh *EventHandler) Remove(start, end int) {
+func (eh *EventHandler) Remove(start, end Loc) {
e := &TextEvent{
C: eh.buf.Cursor,
EventType: TextEventRemove,
}
// Replace deletes from start to end and replaces it with the given string
-func (eh *EventHandler) Replace(start, end int, replace string) {
+func (eh *EventHandler) Replace(start, end Loc, replace string) {
eh.Remove(start, end)
eh.Insert(start, replace)
}