# Copyright (c) 2015, Frappe Technologies Pvt. Ltd. and Contributors
# MIT License. See license.txt

from __future__ import unicode_literals

import io
import os
import re

import frappe
from frappe.model.document import get_controller
from frappe.website.utils import can_cache, delete_page_cache, extract_comment_tag, extract_title
from werkzeug.routing import Map, Rule, NotFound

def resolve_route(path):
	"""Returns the page route object based on searching in pages and generators.
	The `www` folder is also a part of generator **Web Page**.

	The only exceptions are `/about` and `/contact` these will be searched in Web Pages
	first before checking the standard pages."""

	if path not in ("about", "contact"):
		context = get_page_info_from_template(path)
		if context:
			return context
		return get_page_context_from_doctype(path)
	else:
		context = get_page_context_from_doctype(path)
		if context:
			return context
		return get_page_info_from_template(path)

def get_page_context(path):
	page_context = None
	if can_cache():
		page_context_cache = frappe.cache().hget("page_context", path) or {}
		page_context = page_context_cache.get(frappe.local.lang, None)

	if not page_context:
		page_context = make_page_context(path)
		if can_cache(page_context.no_cache):
			page_context_cache[frappe.local.lang] = page_context
			frappe.cache().hset("page_context", path, page_context_cache)

	return page_context

def make_page_context(path):
	context = resolve_route(path)
	if not context:
		raise frappe.PageDoesNotExistError

	context.doctype = context.ref_doctype

	if context.page_title:
		context.title = context.page_title

	context.pathname = frappe.local.path

	return context

def get_page_info_from_template(path):
	'''Return page_info from path'''
	for app in frappe.get_installed_apps(frappe_last=True):
		app_path = frappe.get_app_path(app)

		folders = get_start_folders()

		for start in folders:
			search_path = os.path.join(app_path, start, path)
			options = (search_path, search_path + '.html', search_path + '.md',
				search_path + '/index.html', search_path + '/index.md')
			for o in options:
				option = frappe.as_unicode(o)
				if os.path.exists(option) and not os.path.isdir(option):
					return get_page_info(option, app, start, app_path=app_path)

	return None

def get_page_context_from_doctype(path):
	page_info = get_page_info_from_doctypes(path)
	if not page_info:
		page_info = get_page_info_from_web_page_with_dynamic_routes(path)

	if page_info:
		return frappe.get_doc(page_info.get("doctype"),
			page_info.get("name")).get_page_info()

def clear_sitemap():
	delete_page_cache("*")

def get_all_page_context_from_doctypes():
	'''
	Get all doctype generated routes (for sitemap.xml)
	'''
	routes = frappe.cache().get_value("website_generator_routes")
	if not routes:
		routes = get_page_info_from_doctypes()
		frappe.cache().set_value("website_generator_routes", routes)

	return routes

def get_page_info_from_doctypes(path=None):
	'''
	Find a document with matching `route` from all doctypes with `has_web_view`=1
	'''
	routes = {}
	for doctype in get_doctypes_with_web_view():
		filters = {}
		controller = get_controller(doctype)
		meta = frappe.get_meta(doctype)

		condition_field = (meta.is_published_field or
		# custom doctypes dont have controllers and no website attribute
			(controller.website.condition_field if not meta.custom else None))

		if condition_field:
			filters[condition_field] = 1

		if path:
			filters['route'] = path

		try:
			for r in frappe.get_all(doctype, fields = ['name', 'route', 'modified'],
				filters = filters, limit = 1):

				routes[r.route] = {"doctype": doctype, "name": r.name, "modified": r.modified}

				# just want one path, return it!
				if path:
					return routes[r.route]
		except Exception as e:
			if not frappe.db.is_missing_column(e): raise e

	return routes

def get_page_info_from_web_page_with_dynamic_routes(path):
	'''
	Query Web Page with dynamic_route = 1 and evaluate if any of the routes match
	'''
	rules, page_info = [], {}

	# build rules from all web page with `dynamic_route = 1`
	for d in frappe.get_all('Web Page', fields = ['name', 'route', 'modified'],
		filters = dict(published = 1, dynamic_route=1)):
		rules.append(Rule('/' + d.route, endpoint = d.name))
		d.doctype = 'Web Page'
		page_info[d.name] = d

	end_point = evaluate_dynamic_routes(rules, path)
	if end_point:
		return page_info[end_point]

def evaluate_dynamic_routes(rules, path):
	'''
	Use Werkzeug routing to evaluate dynamic routes like /project/<name>
	https://werkzeug.palletsprojects.com/en/1.0.x/routing/
	'''
	route_map = Map(rules)
	endpoint = None

	if frappe.local.request:
		urls = route_map.bind_to_environ(frappe.local.request.environ)
		try:
			endpoint, args = urls.match("/" + path)
			path = endpoint
			if args:
				# don't cache when there's a query string!
				frappe.local.no_cache = 1
				frappe.local.form_dict.update(args)

		except NotFound:
			pass

	return endpoint

def get_pages(app=None):
	'''Get all pages. Called for docs / sitemap'''

	def _build(app):
		pages = {}

		if app:
			apps = [app]
		else:
			apps = frappe.local.flags.web_pages_apps or frappe.get_installed_apps()

		for app in apps:
			app_path = frappe.get_app_path(app)

			for start in get_start_folders():
				pages.update(get_pages_from_path(start, app, app_path))

		return pages

	return frappe.cache().get_value('website_pages', lambda: _build(app))

def get_pages_from_path(start, app, app_path):
	pages = {}
	start_path = os.path.join(app_path, start)
	if os.path.exists(start_path):
		for basepath, folders, files in os.walk(start_path):
			# add missing __init__.py
			if not '__init__.py' in files:
				open(os.path.join(basepath, '__init__.py'), 'a').close()

			for fname in files:
				fname = frappe.utils.cstr(fname)
				if not '.' in fname:
					continue
				page_name, extn = fname.rsplit(".", 1)
				if extn in ('js', 'css') and os.path.exists(os.path.join(basepath, page_name + '.html')):
					# js, css is linked to html, skip
					continue

				if extn in ("html", "xml", "js", "css", "md"):
					page_info = get_page_info(os.path.join(basepath, fname),
						app, start, basepath, app_path, fname)
					pages[page_info.route] = page_info
					# print frappe.as_json(pages[-1])

	return pages

def get_page_info(path, app, start, basepath=None, app_path=None, fname=None):
	'''Load page info'''
	if fname is None:
		fname = os.path.basename(path)

	if app_path is None:
		app_path = frappe.get_app_path(app)

	if basepath is None:
		basepath = os.path.dirname(path)

	page_name, extn = fname.rsplit(".", 1)

	# add website route
	page_info = frappe._dict()

	page_info.basename = page_name if extn in ('html', 'md') else fname
	page_info.basepath = basepath
	page_info.page_or_generator = "Page"

	page_info.template = os.path.relpath(os.path.join(basepath, fname), app_path)

	if page_info.basename == 'index':
		page_info.basename = ""

	# get route from template name
	page_info.route = page_info.template.replace(start, '').strip('/')
	if os.path.basename(page_info.route) in ('index.html', 'index.md'):
		page_info.route = os.path.dirname(page_info.route)

	# remove the extension
	if page_info.route.endswith('.md') or page_info.route.endswith('.html'):
		page_info.route = page_info.route.rsplit('.', 1)[0]

	page_info.name = page_info.page_name = page_info.route
	# controller
	page_info.controller_path = os.path.join(basepath, page_name.replace("-", "_") + ".py")

	if os.path.exists(page_info.controller_path):
		controller = app + "." + os.path.relpath(page_info.controller_path,
			app_path).replace(os.path.sep, ".")[:-3]

		page_info.controller = controller

	# get the source
	setup_source(page_info)

	# extract properties from HTML comments
	load_properties_from_source(page_info)

	# extract properties from controller attributes
	load_properties_from_controller(page_info)

	page_info.build_version = frappe.utils.get_build_version()

	return page_info

def get_frontmatter(string):
	"""
	Reference: https://github.com/jonbeebe/frontmatter
	"""
	import yaml

	fmatter = ""
	body = ""
	result = re.compile(r'^\s*(?:---|\+\+\+)(.*?)(?:---|\+\+\+)\s*(.+)$', re.S | re.M).search(string)

	if result:
		fmatter = result.group(1)
		body = result.group(2)

	return {
		"attributes": yaml.safe_load(fmatter),
		"body": body,
	}

def setup_source(page_info):
	'''Get the HTML source of the template'''
	jenv = frappe.get_jenv()
	source = jenv.loader.get_source(jenv, page_info.template)[0]
	html = ''

	if page_info.template.endswith(('.md', '.html')):
		# extract frontmatter block if exists
		try:
			# values will be used to update page_info
			res = get_frontmatter(source)
			if res['attributes']:
				page_info.update(res['attributes'])
				source = res['body']
		except Exception:
			pass

		if page_info.template.endswith('.md'):
			source = frappe.utils.md_to_html(source)
			page_info.page_toc_html = source.toc_html

			if not page_info.show_sidebar:
				source = '<div class="from-markdown">' + source + '</div>'

	if not page_info.base_template:
		page_info.base_template = get_base_template(page_info.route)

	if 	page_info.template.endswith(('.html', '.md', )) and \
		'{%- extends' not in source and '{% extends' not in source:
		# set the source only if it contains raw content
		html = source

	# load css/js files
	js_path = os.path.join(page_info.basepath, (page_info.basename or 'index') + '.js')
	if os.path.exists(js_path) and '{% block script %}' not in html:
		with io.open(js_path, 'r', encoding = 'utf-8') as f:
			js = f.read()
			page_info.colocated_js = js

	css_path = os.path.join(page_info.basepath, (page_info.basename or 'index') + '.css')
	if os.path.exists(css_path) and '{% block style %}' not in html:
		with io.open(css_path, 'r', encoding='utf-8') as f:
			css = f.read()
			page_info.colocated_css = css

	if html:
		page_info.source = html
		page_info.base_template =  page_info.base_template or 'templates/web.html'
	else:
		page_info.source = ''

	# show table of contents
	setup_index(page_info)

def get_base_template(path=None):
	'''
	Returns the `base_template` for given `path`.
	The default `base_template` for any web route is `templates/web.html` defined in `hooks.py`.
	This can be overridden for certain routes in `custom_app/hooks.py` based on regex pattern.
	'''
	if not path:
		path = frappe.local.request.path

	base_template_map = frappe.get_hooks("base_template_map") or {}
	patterns = list(base_template_map.keys())
	patterns_desc = sorted(patterns, key=lambda x: len(x), reverse=True)
	for pattern in patterns_desc:
		if re.match(pattern, path):
			templates = base_template_map[pattern]
			base_template = templates[-1]
			return base_template

def setup_index(page_info):
	'''Build page sequence from index.txt'''
	if page_info.basename=='':
		# load index.txt if loading all pages
		index_txt_path = os.path.join(page_info.basepath, 'index.txt')
		if os.path.exists(index_txt_path):
			page_info.index = open(index_txt_path, 'r').read().splitlines()

def load_properties_from_source(page_info):
	'''Load properties like no_cache, title from source html'''

	if not page_info.title:
		page_info.title = extract_title(page_info.source, page_info.route)

	base_template = extract_comment_tag(page_info.source, 'base_template')
	if base_template:
		page_info.base_template = base_template

	if (page_info.base_template
		and "{%- extends" not in page_info.source
		and "{% extends" not in page_info.source
		and "</body>" not in page_info.source):
		page_info.source = '''{{% extends "{0}" %}}
			{{% block page_content %}}{1}{{% endblock %}}'''.format(page_info.base_template, page_info.source)

	if "<!-- no-breadcrumbs -->" in page_info.source:
		page_info.no_breadcrumbs = 1

	if "<!-- show-sidebar -->" in page_info.source:
		page_info.show_sidebar = 1

	if "<!-- add-breadcrumbs -->" in page_info.source:
		page_info.add_breadcrumbs = 1

	if "<!-- no-header -->" in page_info.source:
		page_info.no_header = 1

	if "<!-- add-next-prev-links -->" in page_info.source:
		page_info.add_next_prev_links = 1

	if "<!-- no-cache -->" in page_info.source:
		page_info.no_cache = 1

	if "<!-- no-sitemap -->" in page_info.source:
		page_info.sitemap = 0

	if "<!-- sitemap -->" in page_info.source:
		page_info.sitemap = 1

def load_properties_from_controller(page_info):
	if not page_info.controller: return

	module = frappe.get_module(page_info.controller)
	if not module: return

	for prop in ("base_template_path", "template", "no_cache",
		"sitemap", "condition_field"):
		if hasattr(module, prop):
			page_info[prop] = getattr(module, prop)

def get_doctypes_with_web_view():
	'''Return doctypes with Has Web View or set via hooks'''
	def _get():
		installed_apps = frappe.get_installed_apps()
		doctypes = frappe.get_hooks("website_generators")
		doctypes += [d.name for d in frappe.get_all('DocType', 'name, module',
			dict(has_web_view=1)) if frappe.local.module_app[frappe.scrub(d.module)] in installed_apps]
		return doctypes

	return frappe.cache().get_value('doctypes_with_web_view', _get)

def get_start_folders():
	return frappe.local.flags.web_pages_folders or ('www', 'templates/pages')