Merge branch 'scroll-options' of sloum/bombadillo into master

Closes #13 & #14

cui/window.go

@@ -111,3 +111,69 @@ func (w *Window) ScrollUp() {
 		fmt.Print("\a")
 	}
 }
+
+func (w *Window) PageDown() {
+	var borderThickness int
+	if w.drawBox {
+		borderThickness = -1
+	} else {
+		borderThickness = 1
+	}
+
+	height := w.Box.row2 - w.Box.row1 + borderThickness
+	contentLength := len(w.Content)
+	if w.Scrollposition < contentLength-height {
+		w.Scrollposition += height
+		if w.Scrollposition > contentLength-height {
+			w.Scrollposition = contentLength-height
+		}
+	} else {
+		fmt.Print("\a")
+	}
+}
+
+func (w *Window) PageUp() {
+	var borderThickness int
+	if w.drawBox {
+		borderThickness = -1
+	} else {
+		borderThickness = 1
+	}
+
+	height := w.Box.row2 - w.Box.row1 + borderThickness
+	contentLength := len(w.Content)
+	if w.Scrollposition > 0 && height < contentLength {
+		w.Scrollposition -= height
+		if w.Scrollposition < 0 {
+			w.Scrollposition = 0
+		}
+	} else {
+		fmt.Print("\a")
+	}
+}
+
+func (w *Window) ScrollHome() {
+	if w.Scrollposition > 0 {
+		w.Scrollposition = 0
+	} else {
+		fmt.Print("\a")
+	}
+}
+
+func (w *Window) ScrollEnd() {
+	var borderThickness int
+	if w.drawBox {
+		borderThickness = -1
+	} else {
+		borderThickness = 1
+	}
+
+	height := w.Box.row2 - w.Box.row1 + borderThickness
+
+	contentLength := len(w.Content)
+	if w.Scrollposition < contentLength-height {
+		w.Scrollposition = contentLength-height
+	} else {
+		fmt.Print("\a")
+	}
+}

main.go

@@ -487,6 +487,18 @@ func main() {
 			screen.ReflashScreen(false)
 		case 'q', 'Q':
 			cui.Exit()
+		case 'g':
+			screen.Windows[screen.Activewindow].ScrollHome()
+			screen.ReflashScreen(false)
+		case 'G':
+			screen.Windows[screen.Activewindow].ScrollEnd()
+			screen.ReflashScreen(false)
+		case 'd':
+			screen.Windows[screen.Activewindow].PageDown()
+			screen.ReflashScreen(false)
+		case 'u':
+			screen.Windows[screen.Activewindow].PageUp()
+			screen.ReflashScreen(false)
 		case 'b':
 			success := history.GoBack()
 			if success {