import logging
from gevent import subprocess
import gevent
import os
import functools
import os

LOGGER = logging.getLogger('fqrouter.%s' % __name__)

BUSYBOX_PATH = '/data/data/fq.router2/busybox'
PYTHON_PATH = '/data/data/fq.router2/python/bin/python'
PYTHON_HOME = '/data/data/fq.router2/python'
USE_SU = False


def launch_python(name, args, on_exit=None):
 command = [PYTHON_PATH, '-m', name] + list(args)
 LOGGER.info('launch python: %s' % ' '.join(command))
 env = os.environ.copy()
 env['PYTHONHOME'] = PYTHON_HOME
 if USE_SU:
 proc = subprocess.Popen('su', stdout=subprocess.PIPE, stderr=subprocess.STDOUT, stdin=subprocess.PIPE, env=env)
 proc.terminate = functools.partial(sudo_kill, proc.pid)
 proc.stdin.write('PYTHONHOME=%s ' % PYTHON_HOME)
 proc.stdin.write(' '.join(command))
 proc.stdin.write('\nexit\n')
 else:
 proc = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, env=env)
 gevent.sleep(0.5)
 retcode = proc.poll()
 if retcode:
 try:
 output, _ = proc.communicate()
 LOGGER.error('%s exit %s output: %s' % (name, retcode, output))
 except:
 LOGGER.exception('failed to log %s exit output' % name)
 raise Exception('failed to start %s' % name)
 LOGGER.info('%s started: %s' % (name, proc.pid))
 if USE_SU:
 proc.terminate = functools.partial(sudo_kill, name)
 gevent.spawn(monitor_process, name, proc, on_exit)
 return proc

def find_real_pid(name):
 for pid in os.listdir('/proc'):
 cmdline_file = os.path.join('/proc', pid, 'cmdline')
 if os.path.exists(cmdline_file):
 with open(cmdline_file) as f:
 cmdline = f.read()
 if name in cmdline:
 return pid
 return None

def sudo_kill(name):
 pid = find_real_pid(name)
 if pid:
 LOGGER.info('kill %s' % pid)
 proc = subprocess.Popen('su', stdin=subprocess.PIPE)
 proc.stdin.write('exec /data/data/fq.router2/busybox kill %s\n' % pid)
 proc.communicate()
 else:
 LOGGER.info('%s not found in /proc' % name)

def monitor_process(name, proc, on_exit):
 try:
 output, _ = proc.communicate()
 if proc.poll():
 LOGGER.error('%s output: %s' % (name, output[-1000:]))
 except:
 LOGGER.exception('%s died' % name)
 finally:
 LOGGER.info('%s exited' % name)
 if on_exit:
 try:
 on_exit()
 except:
 LOGGER.exception('failed to execute on_exit hook for %s' % name)


def call(args):
 if USE_SU:
 proc = subprocess.Popen('su', stdin=subprocess.PIPE)
 proc.stdin.write(' '.join(args))
 proc.stdin.write('\nexit\n')
 proc.communicate()
 return proc.poll()
 else:
 return subprocess.call(args)


def check_call(args):
 if USE_SU:
 proc = subprocess.Popen('su', stdin=subprocess.PIPE)
 proc.stdin.write(' '.join(args))
 proc.stdin.write('\nexit\n')
 proc.communicate()
 retcode = proc.poll()
 if retcode:
 raise subprocess.CalledProcessError(retcode, args)
 return 0
 else:
 return subprocess.check_call(args)


def check_output(args):
 if USE_SU:
 proc = subprocess.Popen('su', stdout=subprocess.PIPE, stderr=subprocess.STDOUT, stdin=subprocess.PIPE)
 proc.stdin.write(' '.join(args))
 proc.stdin.write('\nexit\n')
 output = proc.communicate()[0]
 retcode = proc.poll()
 if retcode:
 raise subprocess.CalledProcessError(retcode, args, output=output)
 return output
 else:
 return subprocess.check_output(args, stderr=subprocess.STDOUT)


def Popen(args, **kwargs):
 if USE_SU:
 proc = subprocess.Popen('su', stdin=subprocess.PIPE, **kwargs)
 proc.stdin.write('PYTHONHOME=%s ' % PYTHON_HOME)
 proc.stdin.write(' '.join(args))
 proc.stdin.write('\nexit\n')
 return proc
 else:
 return subprocess.Popen(args, **kwargs)