#!/usr/bin/python

# fusegit - use a git repo directly as a filesystem - python prototype
# public domain )c( 2012, Sam Watkins <sam@nipl.net>

# DONE:
# - mount git HEAD readonly
# 
# TODO:
# - file modes
# - cache directory
# - stop using routefs, make it more efficient

import routes
import routefs
import subprocess
import sys
import os
from os import path
import re

class FuseGit(routefs.RouteFS):
	def __init__(o, *args, **kwargs):
		if not os.environ.get('GIT_DIR'):
			os.environ['GIT_DIR'] = path.realpath('.git')
		super(FuseGit, o).__init__(*args, **kwargs)

	def make_map(o):
		m = routes.Mapper()
		m.connect('/{pathname:.*}', controller='get')
		return m

	def get(o, pathname):
		git_pathname = 'HEAD:'+pathname
		proc = subprocess.Popen(['git', 'ls-tree', '-z', git_pathname], env=os.environ, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
		out, err = proc.communicate() ; status = proc.returncode
		if err and err != 'fatal: not a tree object\n':
			err = re.sub(r'^fatal: ', '', err)
			sys.stderr.write(err)
			return None
		if status == 0:
			entries = [line.split('\t',2)[1] for line in out.split('\0')[:-1]]
			return entries
		else:
			proc = subprocess.Popen(['git', 'show', git_pathname], env=os.environ, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
			out, err = proc.communicate() ; status = proc.returncode
			sys.stderr.write(err)
			if status == 0:
				return out
			else:
				return None

if __name__ == '__main__':
	routefs.main(FuseGit)