feat: updated cache implementation and fixed bugs

internal/cache/state.go

@@ -0,0 +1,60 @@
+package cache
+
+type editorState interface{}
+type selecting struct{}
+type editting struct{}
+
+type Editor struct {
+	state editorState
+}
+
+// transition between state
+
+func NewEditor() Editor {
+	return Editor{state: selecting{}}
+}
+
+func (e *Editor) StartEditting() editting {
+	e.state = editting{}
+	return e.state.(editting)
+}
+
+func (e *Editor) StopEditting() selecting {
+	e.state = selecting{}
+	return e.state.(selecting)
+}
+
+func (s editting) FinishEditting(e *Editor) selecting {
+	e.state = selecting{}
+	return e.state.(selecting)
+}
+
+func (e *Editor) GetState() editorState {
+	return e.state
+}
+
+func (e *Editor) GetStateString() string {
+	switch e.state.(type) {
+	case selecting:
+		return "selecting"
+	case editting:
+		return "editting"
+	}
+	return ""
+}
+
+func (e *Editor) IsEditting() bool {
+	return e.GetStateString() == "editting"
+}
+
+func (e *Editor) IsSelecting() bool {
+	return e.GetStateString() == "selecting"
+}
+
+func test() {
+	editor := NewEditor()
+	editting := editor.StartEditting()
+
+	// ...later on...
+	editting.FinishEditting(&editor)
+}