import SimpleKeyboard from "simple-keyboard";

class KeyboardController {
    constructor(connection) {
        this.connection = connection;
        this.keyboard = null;
        this.keyboardDiv = null;
    }

    _sendKeyPress(l) {
        this.connection.sendMessage("k", [l]);
    }

    mountOn(element) {
        if (this.keyboardDiv)
            return; // Already mounted;

        this.keyboardDiv = document.createElement("div");
        this.keyboardDiv.classList.add("keyboard");
        element.appendChild(this.keyboardDiv);

        this.keyboard = new SimpleKeyboard(this.keyboardDiv, {
            onKeyPress: this.onKeyPress.bind(this),
            mergeDisplay: true,
            layoutName: "default",
            // refer to: https://hodgef.com/simple-keyboard/demos/?d=mobile
            layout: {
                default: [
                    "q w e r t y u i o p",
                    "a s d f g h j k l",
                    "{shift} z x c v b n m {backspace}",
                    "{numbers} {space} {ent}"
                ],
                shift: [
                    "Q W E R T Y U I O P",
                    "A S D F G H J K L",
                    "{shift} Z X C V B N M {backspace}",
                    "{numbers} {space} {ent}"
                ],
                numbers: ["1 2 3", "4 5 6", "7 8 9", "{abc} 0 {backspace}"]
            },
            display: {
                "{numbers}": "123",
                "{ent}": "return",
                "{escape}": "esc ⎋",
                "{tab}": "tab ⇥",
                "{backspace}": "⌫",
                "{capslock}": "caps lock ⇪",
                "{shift}": "⇧",
                "{controlleft}": "ctrl ⌃",
                "{controlright}": "ctrl ⌃",
                "{altleft}": "alt ⌥",
                "{altright}": "alt ⌥",
                "{metaleft}": "cmd ⌘",
                "{metaright}": "cmd ⌘",
                "{abc}": "ABC"
            }
        });
    }

    unmount() {
        if (!this.keyboardDiv)
            return; // Not mounted - don't do anything

        this.keyboardDiv.parentElement.removeChild(this.keyboardDiv);
        this.keyboardDiv = null;
    }

    onKeyPress(button) {
        if (button === "{shift}" || button === "{lock}")
            return this.handleShift();
        if (button === "{numbers}" || button === "{abc}")
            return this.handleNumbers();
        
        this._sendKeyPress(button);
    }

    handleShift() {
        this.keyboard.setOptions({
            layoutName: this.keyboard.options.layoutName === "default" ? "shift" : "default"
        });
    }

    handleNumbers() {
        this.keyboard.setOptions({
            layoutName: this.keyboard.options.layoutName !== "numbers" ? "numbers" : "default"
        });
    }
}

export default KeyboardController;