# Copyright (c) 2013, Web Notes Technologies Pvt. Ltd. and Contributors
# MIT License. See license.txt

from __future__ import unicode_literals
import webnotes
import mimetypes, json

from webnotes.website.context import get_context
from webnotes.website.utils import scrub_relative_urls, get_home_page, can_cache

from webnotes.website.permissions import get_access, clear_permissions

class PageNotFoundError(Exception): pass

def render(path):
	"""render html page"""
	path = resolve_path(path)
	
	try:
		data = render_page(path)
	except Exception:
		path = "error"
		data = render_page(path)
	
	data = set_content_type(data, path)
	webnotes._response.data = data
	webnotes._response.headers[b"Page Name"] = path.encode("utf-8")
	
def render_page(path):
	"""get page html"""
	cache_key = ("page_context:{}" if is_ajax() else "page:{}").format(path)

	out = None
	
	# try memcache
	if can_cache():
		out = webnotes.cache().get_value(cache_key)
		if out and is_ajax():
			out = out.get("data")
			
	if out:
		if hasattr(webnotes, "_response"):
			webnotes._response.headers[b"From Cache"] = True
		
		return out
	
	return build(path)
	
def build(path):
	if not webnotes.conn:
		webnotes.connect()
	
	build_method = (build_json if is_ajax() else build_page)
	try:
		return build_method(path)

	except webnotes.DoesNotExistError:
		hooks = webnotes.get_hooks()
		if hooks.website_catch_all:
			return build_method(hooks.website_catch_all[0])
		else:
			return build_method("404")
	
def build_json(path):
	return get_context(path).data
	
def build_page(path):
	context = get_context(path)
	
	html = webnotes.get_template(context.base_template_path).render(context)
	html = scrub_relative_urls(html)
		
	if can_cache(context.no_cache):
		webnotes.cache().set_value("page:" + path, html)
	
	return html	
	
def is_ajax():
	return webnotes.get_request_header("X-Requested-With")=="XMLHttpRequest"
	
def resolve_path(path):
	if not path:
		path = "index"
			
	if path.endswith('.html'):
		path = path[:-5]
		
	if path == "index":
		path = get_home_page()
		
	return path

def set_content_type(data, path):
	if isinstance(data, dict):
		webnotes._response.headers[b"Content-Type"] = b"application/json; charset: utf-8"
		data = json.dumps(data)
		return data
	
	webnotes._response.headers[b"Content-Type"] = b"text/html; charset: utf-8"
	
	if "." in path and not path.endswith(".html"):
		content_type, encoding = mimetypes.guess_type(path)
		webnotes._response.headers[b"Content-Type"] = content_type.encode("utf-8")
	
	return data

def clear_cache(path=None):
	cache = webnotes.cache()
	
	if path:
		delete_page_cache(path)
		
	else:
		for p in webnotes.conn.sql_list("""select name from `tabWebsite Sitemap`"""):
			if p is not None:
				delete_page_cache(p)
		
		cache.delete_value("home_page")
		clear_permissions()
	
	for method in webnotes.get_hooks("website_clear_cache"):
		webnotes.get_attr(method)(path)

def delete_page_cache(path):
	cache = webnotes.cache()
	cache.delete_value("page:" + path)
	cache.delete_value("page_context:" + path)
	cache.delete_value("sitemap_options:" + path)