Class KeyLogger

packages/pi-tui/test/key-tester.ts:10–101

* Simple key code logger component

 * Simple key code logger component
 */
class KeyLogger implements Component {
	private log: string[] = [];
	private maxLines = 20;
	private tui: TUI;
	private terminal: ProcessTerminal;

	constructor(tui: TUI, terminal: ProcessTerminal) {
		this.tui = tui;
		this.terminal = terminal;
	}

	handleInput(data: string): void {
		// Handle Ctrl+C (raw or Kitty protocol) for exit
		if (matchesKey(data, "ctrl+c")) {
			this.tui.stop();
			console.log("\nExiting...");
			process.exit(0);
		}

		// Convert to various representations
		const hex = Buffer.from(data).toString("hex");
		const charCodes = Array.from(data)
			.map((c) => c.charCodeAt(0))
			.join(", ");
		const repr = data
			.replace(/\x1b/g, "\\x1b")
			.replace(/\r/g, "\\r")
			.replace(/\n/g, "\\n")
			.replace(/\t/g, "\\t")
			.replace(/\x7f/g, "\\x7f");

		const logLine = `Hex: ${hex.padEnd(20)} | Chars: [${charCodes.padEnd(15)}] | Repr: "${repr}"`;

		this.log.push(logLine);

		// Keep only last N lines
		if (this.log.length > this.maxLines) {
			this.log.shift();
		}

		// Request re-render to show the new log entry
		this.tui.requestRender();
	}

	invalidate(): void {
		// No cached state to invalidate currently
	}

	private protocolName(): string {
		if (this.terminal.kittyProtocolActive) return "kitty";
		if (this.terminal.modifyOtherKeysActive) return "modifyOtherKeys";
		return "legacy";
	}

	private fit(line: string, width: number): string {
		return truncateToWidth(line, width).padEnd(width);
	}