#! /usr/bin/env python3
# encoding: utf-8

import jsmin
import json
import subprocess
import sys

def load_cfg(path):
	with open(path) as f:
		return json.loads(jsmin.jsmin(f.read()))

if __name__ == "__main__":
	# try config files in the order they are passed to us
	# first one wins
	
	cfg = None
	
	for path in sys.argv[1:]:
		try:
			cfg = load_cfg(path)
			print("> using %s" %(path))
			break
		except Exception as e:
			print("! cfg file %s failed to load (%s)" %(path, e))
			
	
	if not cfg:
		print("! unable to load any configuration")
		sys.exit(1)
	
	command = ["/usr/bin/ssh", "-o", "ServerAliveInterval 45", "-o", "ServerAliveCountMax 2", "-o", "ExitOnForwardFailure yes", "-N"]
	
	for m in cfg["mapping"]:
		command.append("-R")
		command.append("%d:localhost:%d" %(m["remote"], m["local"]))
	
	command.append("%s@%s" %(cfg["user"], cfg["host"]))
	
	subprocess.run(command)