package io.gitlab.jfronny.inceptum.launcher.util;

import io.gitlab.jfronny.commons.OSUtils;
import io.gitlab.jfronny.inceptum.common.Utils;

import java.io.BufferedReader;
import java.io.InputStreamReader;

public class ProcessUtils {
    public static boolean isProcessAlive(String pid) {
        if (OSUtils.TYPE == OSUtils.Type.WINDOWS)
            return isProcessIdRunning(pid, "tasklist",  "/FI",  "PID eq " + pid);
        return isProcessIdRunning(pid, "ps", "-p", pid);
    }

    public static boolean kill(String pid) {
        //TODO test on windows
        if (OSUtils.TYPE == OSUtils.Type.WINDOWS)
            return kill("taskkill", "/f", "/pid", pid);
        return kill("kill", "--timeout", "500", "KILL", pid);
    }

    private static boolean isProcessIdRunning(String pid, String... command) {
        try {
            Runtime rt = Runtime.getRuntime();
            Process pr = rt.exec(command);

            try (InputStreamReader isReader = new InputStreamReader(pr.getInputStream());
                 BufferedReader bReader = new BufferedReader(isReader)) {
                String strLine;
                while ((strLine = bReader.readLine()) != null) {
                    if (strLine.contains(" " + pid + " ")) {
                        return true;
                    }
                }
            }
            return false;
        } catch (Exception e) {
            Utils.LOGGER.error("Could not get process state", e);
            return true;
        }
    }

    private static boolean kill(String... command) {
        try {
            Runtime rt = Runtime.getRuntime();
            Process pr = rt.exec(command);
            pr.waitFor();
            Thread.sleep(100); // Ensure the signal is processed by waiting this randomly picked amount of time
            return pr.exitValue() == 0;
        } catch (Exception e) {
            Utils.LOGGER.error("Could not kill process", e);
            return false;
        }
    }
}