#! /usr/bin/env python

import psutil
from subprocess import PIPE

CWD = "/home/tim/minecraft/" # Path to where Minecraft lives
JAVA_EXE = "/usr/lib/jvm/java-6-sun-1.6.0.24/jre/bin/java"
MINECRAFT_JAR = "minecraft_server-1.1.jar"
MINECRAFT_COMMAND = "{0} -Xmx1024M -Xms1024M -jar {1} nogui".format(JAVA_EXE, MINECRAFT_JAR).split()
SCREEN_COMMAND = "screen -d -m -S minecraft".split()

def check_minecraft(process):
    if process.name == "java":
        if [process.exe] + process.cmdline[1:] == MINECRAFT_COMMAND:
            print "Minecraft is up and running!"
            return True

def start_minecraft():
    print "Minecraft isn't running. Starting it with following command: {0}".format(
            " ".join(SCREEN_COMMAND + MINECRAFT_COMMAND))
    process = psutil.Popen(SCREEN_COMMAND + MINECRAFT_COMMAND, stdout=PIPE, cwd=CWD)

for p in psutil.process_iter():
    if check_minecraft(p):
        break
else:
    start_minecraft()