#!/usr/bin/python

# Copyright (c) 2007-2008 Mozilla Foundation
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
# DEALINGS IN THE SOFTWARE.

from __future__ import print_function, with_statement

import os
import sys
import re
import string
import gzip

# Several "try" blocks for python2/3 differences (@secretrobotron)
try:
  import httplib
except ImportError:
  import http.client as httplib

try:
  import urlparse
except ImportError:
  import urllib.parse as urlparse

try:
  from BytesIO import BytesIO
except ImportError:
  from io import BytesIO

try:
  maketrans = str.maketrans
except AttributeError:
  maketrans = string.maketrans

#
# Begin
#
extPat = re.compile(r'^.*\.([A-Za-z]+)$')
extDict = {
  'html' : 'text/html',
  'htm' : 'text/html',
  'xhtml' : 'application/xhtml+xml',
  'xht' : 'application/xhtml+xml',
  'xml' : 'application/xml',
}

forceXml = False
forceHtml = False
gnu = False
errorsOnly = False
encoding = None
fileName = None
contentType = None
inputHandle = None
service = 'https://html5.validator.nu/'

argv = sys.argv[1:]

#
# Parse command line input
#
for arg in argv:
  if '--help' == arg:
    print('-h : force text/html')
    print('-x : force application/xhtml+xml')
    print('-g : GNU output')
    print('-e : errors only (no info or warnings)')
    print('--encoding=foo : declare encoding foo')
    print('--service=url  : the address of the HTML5 validator')
    print('One file argument allowed. Leave out to read from stdin.')
    sys.exit(0)
  elif arg.startswith('--encoding='):
    encoding = arg[11:]
  elif arg.startswith('--service='):
    service = arg[10:]
  elif arg.startswith('--'):
      sys.stderr.write('Unknown argument %s.\n' % arg)
      sys.exit(2)
  elif arg.startswith('-'):
    for c in arg[1:]:
      if 'x' == c:
        forceXml = True
      elif 'h' == c:
        forceHtml = True
      elif 'g' == c:
        gnu = True
      elif 'e' == c:
        errorsOnly = True
      else:
        sys.stderr.write('Unknown argument %s.\n' % arg)
        sys.exit(3)
  else:
    if fileName:
      sys.stderr.write('Cannot have more than one input file.\n')
      sys.exit(1)
    fileName = arg

#
# Ensure a maximum of one forced output type
#
if forceXml and forceHtml:
  sys.stderr.write('Cannot force HTML and XHTML at the same time.\n')
  sys.exit(2)

#
# Set contentType
#
if forceXml:
  contentType = 'application/xhtml+xml'
elif forceHtml:
  contentType = 'text/html'
elif fileName:
  m = extPat.match(fileName)
  if m:
    ext = m.group(1)
    ext = ext.translate(maketrans(string.ascii_uppercase, string.ascii_lowercase))
    if ext in extDict:
      contentType = extDict[ext]
    else:
      sys.stderr.write('Unable to guess Content-Type from file name. Please force the type.\n')
      sys.exit(3)
  else:
    sys.stderr.write('Could not extract a filename extension. Please force the type.\n')
    sys.exit(6)
else:
  sys.stderr.write('Need to force HTML or XHTML when reading from stdin.\n')
  sys.exit(4)

if encoding:
  contentType = '%s; charset=%s' % (contentType, encoding)

#
# Read the file argument (or STDIN)
#
if fileName:
  inputHandle = fileName
else:
  inputHandle = sys.stdin

with open(inputHandle, mode='rb') as inFile:
  data = inFile.read()
  with BytesIO() as buf:
    # we could use another with block here, but it requires Python 2.7+
    zipFile = gzip.GzipFile(fileobj=buf, mode='wb')
    zipFile.write(data)
    zipFile.close()
    gzippeddata = buf.getvalue()

#
# Prepare the request
#
url = service

if gnu:
  url = url + '?out=gnu'
else:
  url = url + '?out=text'

if errorsOnly:
  url = url + '&level=error'

connection = None
response = None
status = 302
redirectCount = 0

#
# Make the request
#
while status in (302,301,307) and redirectCount < 10:
  if redirectCount > 0:
    url = response.getheader('Location')
  parsed = urlparse.urlsplit(url)

  if redirectCount > 0:
    connection.close() # previous connection
    print('Redirecting to %s' % url)
    print('Please press enter to continue or type \'stop\' followed by enter to stop.')
    if raw_input() != '':
      sys.exit(0)

  if parsed.scheme == 'https':
    connection = httplib.HTTPSConnection(parsed[1])
  else:
    connection = httplib.HTTPConnection(parsed[1])

  headers = {
    'Accept-Encoding': 'gzip',
    'Content-Type': contentType,
    'Content-Encoding': 'gzip',
    'Content-Length': len(gzippeddata),
  }
  urlSuffix = '%s?%s' % (parsed[2], parsed[3])

  connection.connect()
  connection.request('POST', urlSuffix, body=gzippeddata, headers=headers)

  response = connection.getresponse()
  status = response.status

  redirectCount += 1

#
# Handle the response
#
if status != 200:
  sys.stderr.write('%s %s\n' % (status, response.reason))
  sys.exit(5)

if response.getheader('Content-Encoding', 'identity').lower() == 'gzip':
  response = gzip.GzipFile(fileobj=BytesIO(response.read()))

if fileName and gnu:
  quotedName = '"%s"' % fileName.replace("'", '\\042')
  for line in response.read().split('\n'):
    if line:
      sys.stdout.write(quotedName)
      sys.stdout.write(line + '\n')
else:
  output = response.read()
  # python2/3 difference in output's type
  if not isinstance(output, str):
    output = output.decode('utf-8')
  sys.stdout.write(output)

connection.close()