#!/usr/bin/env python
"""Usage: bupa <filename>

Options:
  -h --help     Show this screen.
"""
from jinja2 import Environment, FileSystemLoader
import glob, yaml, docopt, datetime
from docutils import core
from pyatom import AtomFeed


def reST_to_html(s):
	return core.publish_parts(s, writer_name='html4css1')['fragment']

def filename_to_id(file_name):
	return int(file_name.split('/')[-1].
	                     split('-')[0].
	                     split('.')[0])

class Page(object):
	def __init__(self, page_dict):
		self.id = None
		self.title = page_dict['title']
		self.header = page_dict['header']
		self.date = page_dict['date']
		self.author = page_dict['author']
		if 'author_link' in page_dict:
			self.author_link = page_dict['author_link']
		self.body = page_dict['body'][0]

def parse(filename):
	with open(filename, 'r') as file:
		data = file.read()

	frontmatter, *body = data.split('\n\n', 1)
	frontmatter = frontmatter.partition('\n')[2]
	frontmatter = yaml.load(frontmatter)

	page_dict = frontmatter.copy()
	page_dict['body'] = body
	if not 'header' in page_dict:
		page_dict['header'] = page_dict['title']

	page = Page(page_dict)
	return page

def build_journal(env):
	template   = env.get_template('journal.html')
	entry_tmpl = env.get_template('entry.html')
	files = glob.glob('src/journal/*.rst')
	files.sort(key=filename_to_id, reverse=True)

	feed = AtomFeed(
		title="kyrias’ journal",
		subtitle="The lost journal of Kyrias",
		feed_url="https://theos.kyriasis.com/~kyrias/journal.xml",
		url="https://theos.kyriasis.com/~kyrias/journal.html",
		author={'name': 'Johannes Löthberg',
		        'uri': 'https://theos.kyriasis.com/~kyrias/about.html'},
		updated=datetime.datetime.utcnow(),
		generator=('bupa', '', '0.0.1')
	)

	entries = []
	for file in files:
		entry = parse(file)
		entry.id = filename_to_id(file)
		entry.page = file.split('/', 1)[1].split('.', 1)[0] + '.html'
		entry.body = reST_to_html(entry.body)
		entries += [entry]
		with open('build/'+entry.page, 'w') as file:
			file.write(entry_tmpl.render(entry=entry, title='~/journal',
			                             header='The lost journal'))
		feed.add(
			title=entry.title,
			content=entry.body,
			content_type="html",
			author={'name': entry.author, 'uri': entry.author_link},
			url="https://theos.kyriasis.com/~kyrias/"+entry.page,
			updated=entry.date
		)

	with open('build/journal.html', 'w') as file:
		file.write(template.render(entries=entries, title='~/journal',
		                           header='The lost journal'))
	with open('build/journal.xml', 'w') as file:
		file.write(feed.to_string())

def build_page(env, templ_name, pagename):
	template = env.get_template(templ_name)

	page = parse('src/'+pagename+'.rst')
	page.body = reST_to_html(page.body)
	page.article_id = pagename

	with open('build/'+pagename+'.html', 'w') as file:
		file.write(template.render(page=page, title=page.title, header=page.header))

def main():
	arguments = docopt.docopt(__doc__)
	env = Environment(loader=FileSystemLoader('src/templates'))

	if arguments['<filename>'] == 'journal.html':
		build_journal(env)
	elif arguments['<filename>'] == 'index.html':
		build_page(env, 'page.html', 'index')
	elif arguments['<filename>'] == 'about.html':
		build_page(env, 'page.html', 'about')

if __name__ == '__main__':
	main()