# -*- coding: utf-8 -*-
# Written by Wade Leftwich
# Submitted to ASPN Cookbook
# Available at the following URL: http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/146306
# As far as I can tell, this code is public domain

import httplib
import mimetypes
import sys

def post_multipart(host, selector, fields, files):
    """
    Post fields and files to an http host as multipart/form-data.
    fields is a sequence of (name, value) elements for regular form fields.
    files is a sequence of (name, filename, value) elements for data to be uploaded as files
    Return the server's response page.
    """
    content_type, body = encode_multipart_formdata(fields, files)
    try:
        h = httplib.HTTP(host)
        h.putrequest('POST', selector)
        h.putheader('content-type', content_type)
        h.putheader('content-length', str(len(body)))
        h.putheader('Host',host)
        h.endheaders()
        h.send(body)
        errcode, errmsg, headers = h.getreply()
        if h.file:
            return (h.file.read(), errcode, errmsg)
        else:
            return ("", errcode, errmsg)
    except:
        type, value = sys.exc_info()[:2]
        return ("", 999, str(value))

def encode_multipart_formdata(fields, files):
    """
    fields is a sequence of (name, value) elements for regular form fields.
    files is a sequence of (name, filename, value) elements for data to be uploaded as files
    Return (content_type, body) ready for httplib.HTTP instance
    """
    BOUNDARY = '----------ThIs_Is_tHe_bouNdaRY_$'
    CRLF = '\r\n'
    L = []
    for (key, value) in fields:
        L.append('--' + BOUNDARY)
        L.append('Content-Disposition: form-data; name="%s"' % key)
        L.append('')
        L.append(value)
    for (key, filename, value) in files:
        L.append('--' + BOUNDARY)
        L.append('Content-Disposition: form-data; name="%s"; filename="%s"' % (key, filename))
        L.append('Content-Type: %s' % get_content_type(filename))
        L.append('')
        L.append(value)
    L.append('--' + BOUNDARY + '--')
    L.append('')
    body = CRLF.join(L)
    content_type = 'multipart/form-data; boundary=%s' % BOUNDARY
    return content_type, body

def get_content_type(filename):
    return mimetypes.guess_type(filename)[0] or 'application/octet-stream'