Add documentation to the source and and replace 'r' and 'n' with Emacs keybindings

filter.go

@@ -22,11 +22,19 @@ import (
 	"github.com/gdamore/tcell/v2"
 )
 
+// TODO: Right now, filter does not handle terminal resize properly,
+//fix it!
+
+// Screen size
 var xmax int
 var ymax int
 
+// TODO: Make the highlight style configuratble.
+// The style to be used with the current line
 var highlight tcell.Style
 
+// Draws the given `text` to the screen `s` at the given coordinates. Remember that
+// the text will be wrapped if it overflow.
 func drawText(s tcell.Screen, x1, y1, x2, y2 int, style tcell.Style, text string) {
 	row := y1
 	col := x1
@@ -43,6 +51,7 @@ func drawText(s tcell.Screen, x1, y1, x2, y2 int, style tcell.Style, text string
 	}
 }
 
+// Main render function that gets called during the event loop.
 func Render(s tcell.Screen, inputs Items, lowerBound int, upperBound int, current int) {
 	y := 1
 	status := fmt.Sprintf("Current: %d | lower: %d | upper: %d | max: %d", current, lowerBound, upperBound, ymax)
@@ -72,9 +81,11 @@ func main() {
 		log.Fatalf("%+v", err)
 	}
 
+	// TODO: Make the default style configurable
 	defStyle := tcell.StyleDefault.Background(tcell.ColorDefault).Foreground(tcell.ColorDefault)
 	highlight = tcell.StyleDefault.Background(tcell.ColorDarkGray).Foreground(tcell.ColorWhite)
 	currentLine := 0
+	done := false
 
 	// Initialize screen
 	tty, err := tcell.NewDevTty()
@@ -105,22 +116,15 @@ func main() {
 	}
 	defer quit()
 
-	// Here's an example of how to inject a keystroke where it will
-	// be picked up by the next PollEvent call.  Note that the
-	// queue is LIFO, it has a limited length, and PostEvent() can
-	// return an error.
-	// s.PostEvent(tcell.NewEventKey(tcell.KeyRune, rune('a'), 0))
-
-	done := false
 	lowerBound := 0
 	upperBound := min(ymax-3, len(*input))
+
 	// Event loop
 	for {
 		if done {
 			break
 		}
 		s.Clear()
-		//window := (*input)[lowerBound:upperBound]
 		Render(s, input, lowerBound, upperBound, currentLine)
 
 		// Update screen
@@ -141,12 +145,10 @@ func main() {
 				break
 			} else if ev.Key() == tcell.KeyCtrlL {
 				s.Sync()
-			} else if ev.Rune() == 'C' || ev.Rune() == 'c' {
-				s.Clear()
 			} else if ev.Rune() == ' ' {
 				item := (*input)[currentLine]
 				item.Selected = !item.Selected
-			} else if ev.Key() == tcell.KeyUp || ev.Rune() == 'r' {
+			} else if ev.Key() == tcell.KeyUp || ev.Key() == tcell.KeyCtrlP {
 				if currentLine > 0 {
 					currentLine -= 1
 				}
@@ -155,7 +157,7 @@ func main() {
 					upperBound -= 1
 				}
 
-			} else if ev.Key() == tcell.KeyDown || ev.Rune() == 'n' {
+			} else if ev.Key() == tcell.KeyDown || ev.Key() == tcell.KeyCtrlN {
 				if currentLine < len(*input)-1 {
 					currentLine += 1
 				}
@@ -167,7 +169,11 @@ func main() {
 			}
 		}
 	}
+
+	// Deinitialize the screen so we can use the stdout properly
 	s.Fini()
+
+	// Write what ever that got selected to the stdout
 	for _, item := range *input {
 		if item.Selected {
 			fmt.Println(item.Text)

utils.go

@@ -36,6 +36,7 @@ func NewItem(text string) *Item {
 	}
 }
 
+// Pffff Golang, right? :D
 func min(a, b int) int {
 	if a < b {
 		return a
@@ -43,6 +44,9 @@ func min(a, b int) int {
 	return b
 }
 
+// Reads the input from stdin and makes sure that the current
+// process is being run in a pipeline and converts the data
+// to an array of items.
 func ReadFromStdin() (Items, error) {
 	info, err := os.Stdin.Stat()
 	if err != nil {
@@ -50,7 +54,7 @@ func ReadFromStdin() (Items, error) {
 	}
 
 	if info.Mode()&os.ModeCharDevice != 0 {
-		return nil, fmt.Errorf("The command is intended to work with pipes. For example `git log | filter | xarg | ...`")
+		return nil, fmt.Errorf("the command is intended to work with pipes. For example `git log | filter | xarg | ...`")
 	}
 
 	reader := bufio.NewReader(os.Stdin)