/**
 * Control the proxy protocol server.
 */
class ProxyProtocolServer {
    /**
     * Create a new proxy protocol server.
     */
    constructor(ingress_port, egress_port, version) {
        this.python = "python3";

        if (_isWindows()) {
            this.python = "python.exe";
        }

        print("Using python interpreter: " + this.python);
        this.web_server_py = "jstests/sharding/libs/proxy_protocol_server.py";

        this.pid = undefined;
        this.ingress_port = ingress_port;
        this.egress_port = egress_port;

        assert(version === 1 || version === 2);
        this.version = version;
    }

    /**
     * Get the ingress port - the port over which a client wishing to appear proxied should connect.
     *
     * @return {number} ingress port number
     */
    getIngressPort() {
        return this.ingress_port;
    }

    /**
     * Get the egress port - the port that mongos should be listening on for proxied connections.
     *
     * @return {number} egress port number
     */
    getEgressPort() {
        return this.egress_port;
    }

    /**
     * Start the server.
     */
    start() {
        print("Proxy protocol server is listening on port: " + this.ingress_port);
        print("Proxy protocol server is proxying to port: " + this.egress_port);

        let args = [
            this.python,
            "-u",
            this.web_server_py,
            "--service",
            "127.0.0.1:" + this.ingress_port,
            "127.0.0.1:" + this.egress_port + "?pp=v" + this.version
        ];

        clearRawMongoProgramOutput();

        this.pid = _startMongoProgram({args: args});

        assert(checkProgram(this.pid));

        // Wait for the web server to start
        assert.soon(function() {
            return rawMongoProgramOutput().search("Starting proxy protocol server...") !== -1;
        });

        print("Proxy Protocol Server sucessfully started.");
    }

    /**
     * Stop the server.
     */
    stop() {
        stopMongoProgramByPid(this.pid);
    }
}