#!/usr/bin/env python3
## Based on https://pastee.org/api with 2 modifications by thedod:
## 1. Standard 2to3 run
## 2. Added sloppy_get() [use at your own risk] despite advice against
##    such practices at http://stackoverflow.com/a/1732454
import http.client
import optparse
import os
import sys
import threading
import urllib.request, urllib.parse, urllib.error
import urllib.parse
import re
import html

__version__ = (3, 1, 0)

PASTEE_URL = "https://pastee.org"
DEFAULT_LEXER = "text"
DEFAULT_TTL = 30  # days


class Paste:
  """Class representing a paste that has been submitted."""
  def __init__(self, content, lexer, url):
    """Constructor.

    Args:
      content: paste content
      lexer: lexer used for this paste
      url: URL to access the paste
    """
    self.content = content
    self.lexer = lexer
    self.url = url

  def __unicode__(self):
    return self.url

  def __str__(self):
    return str(self.__unicode__)


class PasteClient:
  """Pasting client for a Pastee application.

  Instances of this class can be used to programmatically create new pastes on
  an installation of Pastee (https://pastee.org).

  This class is thread-safe.
  """
  def __init__(self, url=PASTEE_URL):
    """Constructor.

    Args:
      url: URL to Pastee installation (defaults to https://pastee.org)
    """
    parse = urllib.parse.urlsplit(url)
    self._scheme = parse[0]
    self._netloc = parse[1]
    self._lock = threading.Semaphore()

  def sloppy_get(self,paste_id):
    """Assumes a paste with no lexer that doesn't contain "</pre></div>".
Sometimes you're *sure* it won't ;)"""
    if self._scheme == "https":
      self._conn = http.client.HTTPSConnection(self._netloc)
    else:
      self._conn = http.client.HTTPConnection(self._netloc)
    self._conn.request('GET','/{}'.format(paste_id))
    try:
      response = self._conn.getresponse()
      return html.unescape(
        re.findall(
          b'<div class="syntax"><pre>(.*)</pre></div>',
          response.read(), re.MULTILINE|re.DOTALL
        )[0].decode('unicode_escape'))
    except:
      pass  # Todo: error handling :p
    return None

  def paste(self, content, lexer=None, ttl=None, key=None):
    """Create a new paste.

    Args:
      content: string of text to paste
      lexer: lexer to use (defaults to text)
      ttl: time-to-live in days (defaults to 30)
      key: encrypt paste with this key; if not specified, paste is not
           encrypted

    Returns:
      Paste object
    """
    if lexer is None:
      lexer = DEFAULT_LEXER
    if ttl is None:
      ttl = DEFAULT_TTL

    if self._scheme == "https":
      self._conn = http.client.HTTPSConnection(self._netloc)
    else:
      self._conn = http.client.HTTPConnection(self._netloc)

    headers = {"Content-type": "application/x-www-form-urlencoded",
               "Accept": "text/plain"}
    params = {"lexer": lexer,
              "content": content,
              "ttl": int(ttl * 86400)}
    if key is not None:
      params["encrypt"] = "checked"
      params["key"] = key
    self._lock.acquire()
    self._conn.request("POST", "/submit", urllib.parse.urlencode(params), headers)
    response = self._conn.getresponse()
    self._lock.release()
    return self._make_paste(response, content, lexer)


  def paste_file(self, filename, lexer=None, ttl=None, key=None):
    """Create a new paste from a file.

    Args:
      filename: path to file
      lexer: lexer to use (defaults to extension of the file or text)
      ttl: time-to-live in days (defaults to 30)
      key: encrypt paste with this key; if not specified, paste is not
           encrypted

    Returns:
      Paste object
    """
    _, ext = os.path.splitext(filename)
    if lexer is None and ext:
      lexer = ext[1:]  # remove leading period first
    # TODO(ms): need exception handling here
    fd = open(filename, "r")
    content = fd.read()
    fd.close()
    return self.paste(content, lexer=lexer, ttl=ttl, key=key)

  def _make_paste(self, response, content, lexer):
    for (key, value) in response.getheaders():
      if key.lower() == "location":
        return self._clean_url(value)
    return Paste(content, lexer, self._clean_url(value))

  def _clean_url(self, url):
    p = urllib.parse.urlsplit(url)
    scheme = p[0]
    netloc_split = p[1].split(":")
    hostname = netloc_split[0]
    if len(netloc_split) > 1:
      port = int(netloc_split[1])
    else:
      port = scheme == "https" and 443 or 80
    path = p[2]
    port_str = ""
    if port != 80 and scheme == "http":
      port_str = ":%d" % port
    elif port != 443 and scheme == "https":
      port_str = ":%d" % port
    return "%s://%s%s%s" % (scheme, hostname, port_str, path)


def die_with_error(message):
  """Print a message and exit with exit code 1.

  Args:
    message: message to print before exiting
  """
  print("error: %s" % message)
  sys.exit(1)


def main():
  parser = optparse.OptionParser()
  parser.add_option("-l", "--lexer", dest="lexer", metavar="LEXERNAME",
                    help=("Force use of a particular lexer (i.e. c, py). "
                          "This defaults to the extension of the supplied "
                          "filenames, or 'text' if pasting from stdin."))
  parser.add_option("-t", "--ttl", dest="ttl", metavar="DAYS",
                    help=("Number of days before the paste will expire."))
  ## I'd rather not promote server side crypto. Sorry.
  #parser.add_option("-k", "--key", dest="key", metavar="PASSPHRASE",
  #                  help=("Encrypt pastes with this key."))
  (options, filenames) = parser.parse_args()
  lexer = options.lexer
  key = options.key
  try:
    ttl = float(options.ttl)
  except ValueError:
    die_with_error("floating point number must be passed for TTL")
  except TypeError:
    ttl = None

  client = PasteClient()

  if filenames:
    # paste from multiple files
    for filename in filenames:
      print(client.paste_file(filename, lexer=lexer, ttl=ttl, key=key))
  else:
    # paste from stdin
    print(client.paste(sys.stdin.read(), lexer=lexer, ttl=ttl, key=key))


if __name__ == "__main__":
  main()