"""Download stories attachments of a Pivotal Tracker project.

The shell scripts in this directory do not contain the actual code of them
but the instructions of how to get it.

Since I'm not the author of those scripts, I can't post them in this gist
without his permission.

"""
import getpass
import os
import pickle
import xml.dom.minidom


__version__ = '0.1.0'
__author__ = 'German Larrain'


def get_attachment_metadata(element_attachment):
	def get_data_for_tag(tag_name):
		elements_tag = element_attachment.getElementsByTagName(tag_name)
		assert len(elements_tag) == 1
		element_tag = elements_tag[0]

		assert len(element_tag.childNodes) == 1
		node_attachment_tag = element_tag.childNodes[0]
		assert not node_attachment_tag.hasChildNodes()

		return node_attachment_tag.data
	return (
		get_data_for_tag('id'),
		get_data_for_tag('filename'),
		get_data_for_tag('url'),
	)


def download_attachments(attachments_metadata, dir=None):
	user = raw_input("Account user: ")
	password = getpass.getpass("Account password: ")

	exit_status = os.system("bash login-to-PT.sh %s %s" % (user, password))
	if exit_status:
		print("`login-to-PT.sh` failed. Exit code: %s" % exit_status)

	for metadata in attachments_metadata:
		file_id = metadata[0]
		server_filename = metadata[1]
		filename = "%s - %s" % (file_id, server_filename)
		file_path = filename if dir is None else os.path.join(dir, filename)
		print("downloading %s" % file_id)
		exit_status = os.system(
			'bash get-attachment.sh %s "%s"' % (file_id, file_path))
		if exit_status:
			print("`get-attachment.sh` failed. Exit code: %s" % exit_status)


def main():
	pickle_filename = raw_input("pickled file: ")  # xml_stories_423507.p
	pickle_file = open(pickle_filename, 'rb')
	dom_as_xml = pickle.load(pickle_file)
	dom = xml.dom.minidom.parseString(dom_as_xml)

	elements_stories = dom.getElementsByTagName('stories')
	assert len(dom.getElementsByTagName('stories')) == 1
	element_stories = elements_stories[0]

	elements_story = element_stories.getElementsByTagName('story')
	print("number of stories: %s" % len(elements_story))

	elements_attachments_dict = {}
	attachments_metadata = []

	for ix, story in enumerate(elements_story):
		element_attachments = story.getElementsByTagName('attachments')
		if element_attachments:
			elements_attachments_dict[ix] = element_attachments
	print("number of stories with attachment(s): %s" %
	      len(elements_attachments_dict))

	for key in elements_attachments_dict:
		assert len(elements_attachments_dict[key]) == 1
		element_attachments = elements_attachments_dict[key][0]

		story_elements_attachment = element_attachments.getElementsByTagName('attachment')
		assert len(story_elements_attachment) >= 1
		for element_attachment in story_elements_attachment:
			attachments_metadata.append(
				get_attachment_metadata(element_attachment))

	print("number of attachments: %s" % len(attachments_metadata))
	if attachments_metadata:
		download_attachments(attachments_metadata, dir="attachments")
	else:
		print("[INFO] There are no attachments to be downloaded")

if __name__ == '__main__':
	main()