import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.util.Arrays;
import java.util.List;

public class Client {

    private final String HOST;
    private final int PORT;

    public Client(String host, int port){
        this.HOST = host;
        this.PORT = port;
    }

    // will overwrite any existing values for a given key
    public String putKeyValue(String key, String value){
        return send(String.format("Add:%s-%s", key, value));
    }

    // will append values to any existing key
    public String putKeyValueList(String key, String...values){
        return send(String.format("AddList:%s-%s", key, String.join(",", values)));
    }

    // key must point to a single value
    public String getValue(String key){
        return send(String.format("Get:%s", key));
    }

    // key must point to a list
    public List<String> getValues(String key){
        return Arrays.asList(send(String.format("GetList:%s", key)).split(","));
    }

    public void shutdown(){
        send("shutdown:true");
    }

    private String send(String msg){
        try(Socket client = new Socket(HOST, PORT);
            PrintWriter output = new PrintWriter(client.getOutputStream(), true);
            BufferedReader input = new BufferedReader(new InputStreamReader(client.getInputStream()))) {

            //send msg
            output.println(msg);

            // return response
            return input.readLine();
        }catch (IOException e){
            e.printStackTrace();
            return "Error";
        }
    }
}