Basic selectable todo functionality working

Can:
- move between todo items
- toggle checked/unchecked state

Cannot:
- persiste changes to file
- add items
- delete items

todo/display.go

@@ -0,0 +1,31 @@
+package todo
+
+import (
+	"fmt"
+)
+
+func (widget *Widget) display() {
+	widget.View.Clear()
+
+	title := fmt.Sprintf(" 📝 %s ", widget.FilePath)
+	widget.View.SetTitle(title)
+
+	str := ""
+	for idx, item := range widget.list.Items {
+		foreColor, backColor := "white", "black"
+
+		if widget.View.HasFocus() && idx == widget.list.selected {
+			foreColor, backColor = "black", "olive"
+		}
+
+		str = str + fmt.Sprintf(
+			"[%s:%s]|%s| %s[white]\n",
+			foreColor,
+			backColor,
+			item.CheckMark(),
+			item.Text,
+		)
+	}
+
+	fmt.Fprintf(widget.View, "%s", str)
+}

todo/item.go

@@ -0,0 +1,29 @@
+package todo
+
+import(
+	"time"
+)
+
+type Item struct {
+	Checked bool
+	Index   int
+	Text    string
+
+	createdAt time.Time
+	updatedAt time.Time
+}
+
+func (item *Item) CheckMark() string {
+	if item.Checked {
+		return "x"
+	} else {
+		return " "
+	}
+}
+
+func (item *Item) Toggle() {
+	item.Checked = !item.Checked
+	item.updatedAt = time.Now()
+}
+
+

todo/list.go

@@ -0,0 +1,44 @@
+package todo
+
+import ()
+
+type List struct {
+	Items []*Item
+
+	selected int
+}
+
+func (list *List) Len() int {
+	return len(list.Items)
+}
+
+func (list *List) Less(i, j int) bool {
+	return list.Items[i].Index < list.Items[j].Index
+}
+
+func (list *List) Swap(i, j int) {
+	list.Items[i], list.Items[j] = list.Items[j], list.Items[i]
+}
+
+func (list *List) Next() {
+	list.selected = list.selected + 1
+	if list.selected >= len(list.Items) {
+		list.selected = 0
+	}
+}
+
+func (list *List) Prev() {
+	list.selected = list.selected - 1
+	if list.selected < 0 {
+		list.selected = len(list.Items) - 1
+	}
+}
+
+// Toggle switches the checked state of the selected item
+func (list *List) Toggle() {
+	list.Items[list.selected].Toggle()
+}
+
+func (list *List) Unselect() {
+	list.selected = -1
+}

todo/widget.go

@@ -0,0 +1,101 @@
+package todo
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/gdamore/tcell"
+	"github.com/olebedev/config"
+	"github.com/senorprogrammer/wtf/wtf"
+	"gopkg.in/yaml.v2"
+)
+
+// Config is a pointer to the global config object
+var Config *config.Config
+
+type Widget struct {
+	wtf.TextWidget
+
+	FilePath string
+	list     *List
+}
+
+func NewWidget() *Widget {
+	widget := Widget{
+		TextWidget: wtf.NewTextWidget(" 📝 Todo ", "todo"),
+		FilePath:   Config.UString("wtf.mods.todo.filename"),
+
+		list: &List{selected: -1},
+	}
+
+	widget.init()
+	widget.View.SetInputCapture(widget.keyboardIntercept)
+
+	return &widget
+}
+
+/* -------------------- Exported Functions -------------------- */
+
+func (widget *Widget) Refresh() {
+	if widget.Disabled() {
+		return
+	}
+
+	confDir, _ := wtf.ConfigDir()
+
+	fileData, _ := wtf.ReadYamlFile(fmt.Sprintf("%s/%s", confDir, widget.FilePath))
+	yaml.Unmarshal(fileData, &widget.list)
+
+	widget.display()
+	widget.RefreshedAt = time.Now()
+}
+
+/* -------------------- Unexported Functions -------------------- */
+
+func (widget *Widget) init() {
+	_, err := wtf.CreateFile(widget.FilePath)
+	if err != nil {
+		panic(err)
+	}
+}
+
+func (widget *Widget) keyboardIntercept(event *tcell.EventKey) *tcell.EventKey {
+	switch string(event.Rune()) {
+	case " ":
+		// Check/uncheck selected item
+		widget.list.Toggle()
+		widget.display()
+		return nil
+	case "e":
+		// Edit selected item
+		return nil
+	case "n":
+		// Add a new item
+		return nil
+	}
+
+	switch event.Key() {
+	case tcell.KeyCtrlD:
+		// Delete selected item
+		return nil
+	case tcell.KeyDown:
+		widget.list.Next()
+		widget.display()
+		return nil
+	//case tcell.KeySpac:
+	//// Check/uncheck an item
+	//return nil
+	case tcell.KeyEsc:
+		// Unselect the current row and pass the key on through to unselect the widget
+		widget.list.Unselect()
+		widget.display()
+		return event
+	case tcell.KeyUp:
+		// Select next item up
+		widget.list.Prev()
+		widget.display()
+		return nil
+	default:
+		return event
+	}
+}