# coding=utf-8
from __future__ import absolute_import

__author__ = "Gina Häußge <osd@foosel.net>"
__license__ = 'The MIT License <http://opensource.org/licenses/MIT>'
__copyright__ = "Copyright (C) 2015 Gina Häußge - Released under terms of the MIT License"


import codecs
import requests
from contextlib import closing

from sphinx.directives.code import LiteralIncludeReader, LiteralInclude, dedent_lines, \
	nodes, set_source_info, parselinenos, logger, container_wrapper

if False:
	# For type annotation
	from typing import Any, List  # NOQA

cache = dict()

class OnlineIncludeReader(LiteralIncludeReader):

	def read_file(self, filename, location=None):
		# type: (unicode, Any) -> List[unicode]

		global cache
		try:
			if filename in cache:
				lines = cache[filename]
			else:
				with closing(requests.get(filename, stream=True)) as r:
					r.encoding = self.encoding
					lines = r.text.splitlines(True)
					cache[filename] = lines

			if 'tab-width' in self.options:
				lines = [line.expandtabs(self.options['tab-width']) for line in lines]

			return lines
		except (IOError, OSError):
			raise IOError(_('Include file %r not found or reading it failed') % filename)
		except UnicodeError:
			raise UnicodeError(_('Encoding %r used for reading included file %r seems to '
			                     'be wrong, try giving an :encoding: option') %
			                   (self.encoding, filename))


class OnlineIncludeDirective(LiteralInclude):

	def run(self):
		# type: () -> List[nodes.Node]
		document = self.state.document
		if not document.settings.file_insertion_enabled:
			return [document.reporter.warning('File insertion disabled',
			                                  line=self.lineno)]
		env = document.settings.env

		# convert options['diff'] to absolute path
		if 'diff' in self.options:
			_, path = env.relfn2path(self.options['diff'])
			self.options['diff'] = path

		try:
			location = self.state_machine.get_source_and_line(self.lineno)
			url = self.arguments[0]

			reader = OnlineIncludeReader(url, self.options, env.config)
			text, lines = reader.read(location=location)

			retnode = nodes.literal_block(text, text, source=url)
			set_source_info(self, retnode)
			if self.options.get('diff'):  # if diff is set, set udiff
				retnode['language'] = 'udiff'
			elif 'language' in self.options:
				retnode['language'] = self.options['language']
			retnode['linenos'] = ('linenos' in self.options or
			                      'lineno-start' in self.options or
			                      'lineno-match' in self.options)
			retnode['classes'] += self.options.get('class', [])
			extra_args = retnode['highlight_args'] = {}
			if 'emphasize-lines' in self.options:
				hl_lines = parselinenos(self.options['emphasize-lines'], lines)
				if any(i >= lines for i in hl_lines):
					logger.warning('line number spec is out of range(1-%d): %r' %
					               (lines, self.options['emphasize-lines']),
					               location=location)
				extra_args['hl_lines'] = [x + 1 for x in hl_lines if x < lines]
			extra_args['linenostart'] = reader.lineno_start

			if 'caption' in self.options:
				caption = self.options['caption'] or self.arguments[0]
				retnode = container_wrapper(self, retnode, caption)

			# retnode will be note_implicit_target that is linked from caption and numref.
			# when options['name'] is provided, it should be primary ID.
			self.add_name(retnode)

			return [retnode]
		except Exception as exc:
			return [document.reporter.warning(str(exc), line=self.lineno)]


def visit_onlineinclude(translator, node):
	translator.visit_literal_block(node)

def depart_onlineinclude(translator, node):
	translator.depart_literal_block(node)

def setup(app):
	app.add_directive("onlineinclude", OnlineIncludeDirective)

	handler = (visit_onlineinclude, depart_onlineinclude)
	app.add_node(OnlineIncludeDirective, html=handler, latex=handler, text=handler)