class Kernel {
    constructor(config) {
        this.config = config;

        this.executionCount = 0;

        this.session = new Session({
            cwd: this.config.cwd,
            parser: this.config.parser,
            transpile: this.config.transpile,
        });

        this._init();
    }

    _init(initCB) {}
    interrupt(interruptCB) {}
    destroy(destroyCB) {}
    restart(restartCB) {}

    _onShellMessage(message) {}
    _onControlMessage(message) {}
    _onIOPubMessage(message) {}
    _onHBMessage(message) {}
}

class KernelV4 extends Kernel {
    onStdout(data) {}
    onStderr(data) {}
    onShell_xxx(request) {}
}

class KernelV5 extends Kernel {
    onStdout(data) {}
    onStderr(data) {}
    onShell_xxx(request) {}
}

class Config {
    constructor(kernelConfig) {
        this.hideUndefined = kernelConfig.hideUndefined;
        this.initSession = kernelConfig.initSession;
        this.initScripts = kernelConfig.initScripts;
        this.kernelInfoReply = kernelConfig.kernelInfoReply;
        this.protocolVersion = kernelConfig.protocolVersion;

        this.connection = kernelConfig.connection;
        this.parser = kernelConfig.parser;
    }
}

class Connection {
    constructor(connectionConfig) {
        this.config = connectionConfig;
        this.socket = {
            control: new jmp.Socket("router", scheme, key),
            shell: new jmp.Socket("router", scheme, key),
            iopub: new jmp.Socket("pub", scheme, key),
            hb: zmq.createSocket("rep"),
        };
    }

    connect(listeners) {}
    disconnect() {}
}

class Parser{
    constructor() {
        throw new Error("Cannot construct an abstract class");
    }

    getIdentifier(code, position) {
        throw new Error("Not implemented");
    }

    validate(code) {
        throw new Error("Not implemented");
    }
}