#   WikiNote3
#   Copyright © 2020  Lee Yingtong Li (RunasSudo)
#
#   This program is free software: you can redistribute it and/or modify
#   it under the terms of the GNU Affero General Public License as published by
#   the Free Software Foundation, either version 3 of the License, or
#   (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU Affero General Public License for more details.
#
#   You should have received a copy of the GNU Affero General Public License
#   along with this program.  If not, see <https://www.gnu.org/licenses/>.

from .markup import WNMarkdown

import flask

import os
import pickle
import xml.etree.ElementTree as ET

app = flask.Flask(__name__, template_folder='jinja2')

if os.path.exists('index.pickle'):
	try:
		with open('index.pickle', 'rb') as f:
			index = pickle.load(f)
	except:
		print('Error loading index.pickle')
		import traceback; traceback.print_exc()

def get_children(path):
	def child_name(c):
		return os.path.splitext(c)[0]
	
	children = []
	if os.path.isdir(flask.safe_join('./data/pages', path)):
		for child in os.listdir(flask.safe_join('./data/pages', path)):
			child_path = flask.safe_join('./data/pages', path, child)
			
			if child.startswith('_'):
				continue
			
			if os.path.islink(child_path):
				children.append((child_name(child), child_name(os.path.split(os.path.realpath(child_path))[1])))
			else:
				children.append((child_name(child), None))
	children.sort(key=lambda x: x[0][1:] if x[0].startswith('(') else x[0])
	
	return children

@app.route('/')
def index_page():
	children = get_children('')
	
	if not os.path.exists('./data/pages/Home.md'):
		return flask.render_template('page_404.html', page={
			'path': '',
			'title': 'Home',
			'children': children
		})
	
	with(open(fname, 'r')) as f:
		page_source = f.read()
	
	md = WNMarkdown()
	page_content = md.convert(page_source)
	
	return flask.render_template('page_rendered.html', page={
		'path': '',
		'title': 'Home',
		'content': page_content,
		'toc': md.toc_tokens,
		'meta': md.meta,
		'children': children
	})

@app.route('/page/<path:path>')
def page_view(path):
	fname = flask.safe_join('./data/pages', path) + '.md'
	
	if os.path.islink(fname):
		redir_page = '/'.join(path.split('/')[:-1]) + '/' + os.path.splitext(os.readlink(fname))[0]
		return flask.redirect(flask.url_for('page_view', path=redir_page))
	
	children = get_children(path)
	
	if not os.path.exists(fname):
		return flask.render_template('page_404.html', page={
			'path': path,
			'title': path.split('/')[-1],
			'children': children
		})
	
	with(open(fname, 'r')) as f:
		page_source = f.read()
	
	md = WNMarkdown()
	#page_content = md.convert(page_source)
	root = md.parse(page_source)
	
	# Add expand/collapse buttons to h2
	for elem in root:
		if elem.tag == 'h2':
			elem.text += ' '
			btn = ET.SubElement(elem, 'button')
			btn.text = '±'
			btn.set('class', 'expcol')
			btn.set('onclick', 'onClickExpCol(this);')
	
	# Handle collapsed sections
	if root == '':
		page_content = ''
	else:
		if 'collapsed' in flask.request.args:
			for elem in root:
				if elem.tag == 'section':
					elem.set('class', 'collapsed')
		page_content = md.serialise(root)
	
	return flask.render_template('page_rendered.html', page={
		'path': path,
		'title': md.meta['title'] if 'title' in md.meta else path.split('/')[-1],
		'content': page_content,
		'toc': md.toc_tokens,
		'meta': md.meta,
		'children': children,
		'xrefs': index['xrefs'].get(path, [])
	}, collapsed='collapsed' in flask.request.args)

@app.route('/preview/<path:path>')
def page_preview(path):
	fname = flask.safe_join('./data/pages', path) + '.md'
	
	if not os.path.exists(fname):
		return ''
	
	with(open(fname, 'r')) as f:
		page_source = f.read()
	
	md = WNMarkdown()
	page_root = md.parse(page_source)
	
	# Delete all but first section
	for section in list(page_root[1:]):
		page_root.remove(section)
	
	# Delete all but introductory text
	for elem in list(page_root[0][1:]):
		page_root[0].remove(elem)
	
	# Delete footnotes
	def walk_tree(elem):
		last_child = None
		for child in list(elem):
			if child.get('class') == 'footnote-ref':
				if child.tail:
					# Combine tail text
					if last_child is not None:
						last_child.tail += child.tail
					else:
						elem.text += child.tail
				elem.remove(child)
				walk_tree(child)
			else:
				walk_tree(child)
				last_child = child
	walk_tree(page_root[0])
	
	page_content = md.serialise(page_root)
	return page_content

@app.route('/image/<name>')
def image_view(name):
	fname = flask.safe_join(os.getcwd(), './data/images', name[0].upper(), name)
	return flask.send_file(fname)

@app.route('/image/<name>/about')
def image_about(name):
	fname = flask.safe_join(os.getcwd(), './data/images', name[0].upper(), os.path.splitext(name)[0] + '.md')
	
	with(open(fname, 'r')) as f:
		page_source = f.read()
	
	md = WNMarkdown()
	page_content = md.convert(page_source)
	
	return flask.render_template('image_about.html', page={
		'path': name,
		'title': name,
		'content': page_content,
		'meta': md.meta
	})

@app.route('/tag/')
def tags_list():
	return flask.render_template('tags_list.html', tags=sorted(index['tags'].keys()))

@app.route('/tag/<name>')
def tag_view(name):
	if name not in index['tags']:
		return flask.render_template('tag_404.html', name=name)
	
	pages = index['tags'][name]
	pages.sort(key=lambda p: p['kind'])
	pages.sort(key=lambda p: p['path'])
	return flask.render_template('tag_view.html', name=name, pages=pages)

@app.cli.command('index')
def cli_index():
	app.config['SERVER_NAME'] = 'localhost'
	
	with app.app_context():
		tags = {}
		xrefs = {}
		
		base_path = './data/pages'
		for dirpath, dirnames, filenames in os.walk(base_path):
			for fname in filenames:
				if fname.endswith('.md') and not os.path.islink(flask.safe_join(dirpath, fname)):
					page_path = dirpath[len(base_path)+1:] + '/' + fname[:-3]
					
					with(open(flask.safe_join(dirpath, fname), 'r')) as f:
						page_source = f.read()
					md = WNMarkdown()
					md.convert(page_source)
					
					for tag in md.meta.get('tags', []):
						if tag not in tags:
							tags[tag] = []
						tags[tag].append({'kind': 'page', 'path': page_path})
					
					for ref in md.meta.get('refs', []):
						fname_ref = flask.safe_join('./data/pages', ref) + '.md'
						if os.path.islink(fname_ref):
							ref = '/'.join(ref.split('/')[:-1]) + '/' + os.path.splitext(os.readlink(fname_ref))[0]
						
						if ref not in xrefs:
							xrefs[ref] = []
						if page_path not in xrefs[ref]:
							xrefs[ref].append(page_path)
		
		base_path = './data/images'
		for dirpath, dirnames, filenames in os.walk(base_path):
			for fname in filenames:
				if fname.endswith('.md'):
					continue
				
				md_path = flask.safe_join(dirpath, os.path.splitext(fname)[0] + '.md')
				if os.path.exists(md_path):
					with(open(md_path, 'r')) as f:
						page_source = f.read()
					md = WNMarkdown()
					md.convert(page_source)
					
					for tag in md.meta.get('tags', []):
						if tag not in tags:
							tags[tag] = []
						tags[tag].append({'kind': 'image', 'path': fname})
		
		with open('index.pickle', 'wb') as f:
			pickle.dump({
				'tags': tags,
				'xrefs': xrefs
			}, f)

@app.cli.command('redlinks')
def cli_redlinks():
	app.config['SERVER_NAME'] = 'localhost'
	
	redlinks = set()
	
	with app.app_context():
		base_path = './data/pages'
		for dirpath, dirnames, filenames in os.walk(base_path):
			for fname in filenames:
				if fname.endswith('.md'):
					page_path = dirpath[len(base_path)+1:] + '/' + fname[:-3]
					
					with(open(flask.safe_join(dirpath, fname), 'r')) as f:
						page_source = f.read()
					md = WNMarkdown()
					md.convert(page_source)
					
					for redlink in md.meta.get('redlinks', []):
						redlinks.add(redlink)
	
	redlinks = sorted(list(redlinks))
	
	for redlink in redlinks:
		print(redlink)