import urllib.parse

import bs4

import config
import database

def generate_nav(*, soup):
	"""Returns nav_tag"""
	# TODO: Don't generate link to a board if we're at the index
	nav_tag = soup.new_tag('nav')

	with database.connect() as db:
		boards = database.list_boards(db)

	for board in boards:
		url = config.url_prefix + '/' + urllib.parse.quote(board, safe = '') + '/'
		a_tag = soup.new_tag('a', href = url)
		a_tag.string = '/' + board + '/'
		nav_tag.append(a_tag)

	return nav_tag

def generate_header(*, page_title, soup):
	"""Returns header_tag"""
	header_tag = soup.new_tag('header')

	h1_tag = soup.new_tag('h1')
	h1_tag.string = page_title
	header_tag.append(h1_tag)

	return header_tag

def generate_footer(*, soup):
	"""Returns footer_tag"""
	# TODO: Add footer generation
	return soup.new_tag('footer')

def page_skeleton(*, page_title, contents, soup):
	"""Returns html
	Given page title (string) and contents (iteratable of beautifulsoup tags), create the html
	Since most pages have same basic structure, it makes sense to factor this out from page creation functions"""
	# Doctype and head are more or less the same for each page, no need to do anything fancy when adding them
	soup.append(bs4.Doctype('html'))

	head_tag = soup.new_tag('head')
	title_tag = soup.new_tag('title')
	title_tag.string = page_title
	head_tag.append(title_tag)
	soup.append(head_tag)

	# Body consists of (more or less same) header and footer, and varying content
	body_tag = soup.new_tag('body')

	body_tag.append(generate_nav(soup = soup))
	body_tag.append(generate_header(page_title = page_title, soup = soup))

	# contents is an iterable that can contain several tags
	for tag in contents:
		body_tag.append(tag)

	body_tag.append(generate_footer(soup = soup))

	soup.append(body_tag)

	# Use .prettify() to generate nice-looking HTML
	# We are probably never going to serve enough pages for the additional whitespace to count for data usage
	return soup.prettify()

def new_soup():
	"""Returns soup
	Since we need a soup object to create tags, split this from page_skeleton"""
	# Use python's built-in parser for portability
	# We'll be constructing the document programmatically, so start with empty tree
	soup = bs4.BeautifulSoup('', 'html.parser')

	return soup

def board(board_name):
	"""Returns html
	Creates the board index page"""
	# TODO: Creae a board index page
	soup = new_soup()

	page_title = '/' + board_name + '/'

	return page_skeleton(page_title = page_title, contents = [], soup = soup)

def index():
	"""Returns html
	Create the site index"""
	# TODO: Create an index page
	soup = new_soup()
	return page_skeleton(page_title = config.site_name, contents = [], soup = soup)

def login(raw_path, retrying = False):
	"""Returns html
	Creates a page telling the user to log in
	if retrying is true, show a text about username/pass being wrong"""
	# TODO: Take the user back to where they were
	soup = new_soup()

	# TODO: Don't hardcode
	contents = list(bs4.BeautifulSoup('''
		<p>Login to access</p>
		<form action="''' + config.url_prefix + '''/login" method="post">
			<div>
				<input type="text" name="username"/>
			</div>
			<div>
				<input type="password" name="password"/>
			</div>
			<div>
				<input type="submit" value="Login"/>
			</div>
		</form>
	''', 'html.parser'))

	if retrying:
		p_tag = soup.new_tag('p')
		p_tag.string = 'Wrong username or password'
		contents = [contents[0], p_tag] + contents[1:]

	# TODO: Internationalization
	return page_skeleton(page_title = 'Login to ' + config.site_name, contents = contents, soup = soup)

def error_404(path):
	"""Returns html"""
	soup = new_soup()

	p_tag = soup.new_tag('p')
	p_tag.string = path + ' does not exist'

	return page_skeleton(page_title = '404 Not Found', contents = [p_tag], soup = soup)