#!/usr/bin/python
# Recursively list FTP directory contents
#
# Copyright (C) 2013 Peter Wu <lekensteyn@gmail.com>

# Prepend directory name to files and list files:
# awk '/^Directory/{if($0 != "Directory /")dir=substr($0, index($0, "/"))}/^-/{n=index($0,$9);print substr($0,1, n - 1) dir "/" substr($0,n)}'

import sys
from ftplib import FTP
import re

user = "anonymous"
passwd = "anon"
host = None
port = 21
path = "/"

patt_url = re.compile(r"""
^
(?:ftp://)?
(?:
	(?P<user>.+?)
	(?:
		:(?P<passwd>.+?)
	)?
	@
)?
(?P<host>[a-zA-Z0-9.-]+)
(:(?P<port>\d+))?
(?P<path>/.*)?
$
""", re.VERBOSE)

if len(sys.argv) >= 2:
	m = patt_url.match(sys.argv[1])
	if m:
		if m.group("user") is not None:
			user = m.group("user")
		if m.group("passwd") is not None:
			passwd = m.group("passwd")
		host = m.group("host")
		if m.group("port") is not None:
			port = int(m.group("port"))
		if m.group("path") is not None:
			path = m.group("path")

if host is None:
	print("Usage: python", sys.argv[0],
		"[ftp://][user[:pass]@]ftp.example.com[:21][/path]",
		file=sys.stderr)
	sys.exit(1)

# directories for which the contents needs to be retrieved
dirs = []
dirs.append(path)

patt_list = re.compile(r"""
^
.[-rwxXst]{9}\ + # permissions
\d+\ +          # links count
\S+\ +          # owner
\S+\ +          # group
\d+\ +          # size
\S{3}\ +        # month
\d{2}\ +        # day
(?:\d{4,}|\d{2}:\d{2})  # year or time
\ (.+?)         # name
(?:\ ->\ (.+))? # symlink
[\r\n]*         # line contains
$
""", re.VERBOSE)

def get_ls_processor(cwd):
	def process_dir(line):
		print(line)
		if line[0] == 'd':
			m = patt_list.match(line)
			name = m.group(1)
			if cwd == "/":
				dir = "/" + name
			else:
				dir = cwd + "/" + name
			print("Queuing", dir, file=sys.stderr)
			dirs.append(dir)
#		elif line[0] == 'l':
#			m = patt_list.match(line)
#			print("Link", m.group(2))
	return process_dir

with FTP() as ftp:
	ftp.connect(host, port)
	ftp.login(user, passwd)
	print(ftp.getwelcome(), file=sys.stderr)
	while dirs:
		dir = dirs.pop()
		ftp.cwd(dir)
		print("Directory", ftp.pwd())
		ftp.retrlines('LIST', get_ls_processor(dir))
		print("Queue size:", len(dirs), file=sys.stderr)