added terminal app with example hello world

src/bin/HelloWorld.hx

@@ -0,0 +1,17 @@
+package bin;
+
+import lib.TermHandle;
+import kernel.fs.FileHandler.WriteHandle;
+import lib.CLIBase;
+
+class HelloWorld extends CLIBase {
+	public function invoke(handle: TermHandle):Bool {
+		var world:String = "world";
+		if (handle.args.length > 0) {
+			world = handle.args[0];
+		}
+
+		handle.write('Hello, $world!');
+		return true;
+	}
+}

src/bin/Terminal.hx

@@ -0,0 +1,151 @@
+package bin;
+
+import lib.TermHandle;
+import lib.CLIBase;
+import util.Color;
+import kernel.ui.WindowContext;
+import kernel.ui.WindowManager;
+
+class Terminal {
+	private var context:WindowContext;
+	private var input:String = "";
+	private var backlog: Array<String> = [];
+
+	public function new() {}
+
+	public function execute() {
+		this.context = WindowManager.instance.createNewContext();
+
+		this.context.onChar.handle(char -> {
+			this.input += char;
+			this.redrawInput();
+		});
+
+		this.context.onKey.handle(e -> {
+			if (e.keyCode == 259) {
+				this.input = this.input.substr(0, this.input.length - 1);
+				this.redrawInput();
+			} else if (e.keyCode == 257) {
+				this.backlog.push("> " + this.input);
+				var command = this.input;
+				this.input = "";
+				this.redrawBacklog();
+				this.redrawInput();
+				this.invokeCommand(command);
+			}
+		});
+
+		WindowManager.instance.focusContextToOutput(context, "main");
+		this.redrawInput();
+	}
+
+	private function redrawBacklog() {
+		var size = this.context.getSize();
+		var linesAvailable = size.y - 1;
+
+		var start:Int = this.backlog.length - linesAvailable;
+
+		for (i in 0...linesAvailable){
+			var line = this.backlog[start + i];
+
+			this.context.setCursorPos(0, i);
+			this.context.clearLine();
+
+			if (line != null) {
+				this.context.write(line);
+			}
+		}
+		this.moveCursorToInput();
+	}
+
+	private function redrawInput() {
+		var size = this.context.getSize();
+
+		this.context.setCursorPos(0, size.y - 1);
+		this.context.clearLine();
+
+		this.context.setTextColor(Color.Blue);
+		this.context.write("> ");
+
+		this.context.setTextColor(Color.White);
+		this.context.write(this.input);
+
+		this.context.setCursorBlink(true);
+	}
+
+	private function invokeCommand(command: String):Void{
+		var args = this.parseArgs(command);
+
+		if (args.length == 0) {
+			return;
+		}
+		var commandName = args[0];
+
+		// Handle built-in commands
+		switch (commandName) {
+			case "clear":
+				this.clear();
+				return;
+		}
+
+		var commandArgs:Array<String> = args.slice(1);
+		var hadInput = false;
+		var handle = new TermHandle(commandArgs,{
+			onWrite: (s:String) -> {
+				if (!hadInput) {
+					this.backlog.push("");
+					hadInput = true;
+				}
+				this.backlog[this.backlog.length - 1] += s;
+				this.redrawBacklog();
+			},
+			onNewLine: () -> {
+				this.backlog.push("");
+				this.redrawBacklog();
+			}
+		});
+
+		var prog:CLIBase = getProgByName(commandName);
+
+		if (prog == null) {
+			this.backlog.push("Command not found: " + commandName);
+			this.redrawBacklog();
+			return;
+		}
+
+		this.context.setCursorBlink(false);
+
+		prog.invoke(handle);
+
+		// Cleanup extra newline
+		if (this.backlog[this.backlog.length - 1] == "") {
+			this.backlog.pop();
+		}
+
+		this.redrawInput();
+	}
+
+	private function parseArgs(command: String): Array<String> {
+		// TODO: tim and quote handling
+		return command.split(" ");
+	}
+
+	private function clear() {
+		this.backlog = [];
+		this.redrawBacklog();
+	}
+
+	private function getProgByName(name: String): CLIBase {
+		switch (name) {
+			case "hello":
+				return new HelloWorld();
+			default:
+				return null;
+		}
+	}
+
+	private function moveCursorToInput() {
+		var size = this.context.getSize();
+		this.context.setCursorPos(this.input.length + 2, size.y - 1);
+	}
+}

src/lib/CLIBase.hx

@@ -0,0 +1,6 @@
+package lib;
+
+abstract class CLIBase {
+	public function new() {};
+	public abstract function invoke(handle: TermHandle): Bool;
+}

src/lib/TermHandle.hx

@@ -0,0 +1,29 @@
+package lib;
+
+import haxe.ds.ReadOnlyArray;
+
+typedef TermHandleEvents = {
+	onWrite: String->Void,
+	onNewLine: Void->Void,
+}
+
+class TermHandle {
+	public final args:ReadOnlyArray<String>;
+	private final events:TermHandleEvents;
+
+	@:allow(bin.Terminal)
+	private function new(args: Array<String>, events: TermHandleEvents) {
+		this.args = args;
+		this.events = events;
+	}
+
+	public function write(s:String) {
+		this.events.onWrite(s);
+	}
+
+	public function writeLn(s:String = "") {
+		if (s != "")
+			this.events.onWrite(s);
+		this.events.onNewLine();
+	}
+}