text: # Copyright (c) 2015, Frappe Technologies Pvt. Ltd. and Contributors
  # License: MIT. See LICENSE
  import frappe
  import re
  from frappe.website.utils import clear_cache
  from frappe.utils import add_to_date, now
  
  from frappe import _
  
  @frappe.whitelist(allow_guest=True)
  def add_comment(comment, comment_email, comment_by, reference_doctype, reference_name, route):
  	doc = frappe.get_doc(reference_doctype, reference_name)
  
  	if frappe.session.user == 'Guest' and doc.doctype not in ['Blog Post', 'Web Page']:
  		return
  
  	if not comment.strip():
  		frappe.msgprint(_('The comment cannot be empty'))
  		return False
  
  	url_regex = re.compile(r"http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\(\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+", re.IGNORECASE)
  	email_regex = re.compile(r"(^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+$)", re.IGNORECASE)
  
  	if url_regex.search(comment) or email_regex.search(comment):
  		frappe.msgprint(_('Comments cannot have links or email addresses'))
  		return False
  
  	comments_count = frappe.db.count("Comment", {
  		"comment_type": "Comment",
  		"comment_email": comment_email,
  		"creation": (">", add_to_date(now(), hours=-1))
  	})
  
  	if comments_count > 20:
  		frappe.msgprint(_('Hourly comment limit reached for: {0}').format(frappe.bold(comment_email)))
  		return False
  
  	comment = doc.add_comment(
  		text=comment,
  		comment_email=comment_email,
  		comment_by=comment_by)
  
  	comment.db_set('published', 1)
  
  	# since comments are embedded in the page, clear the web cache
  	if route:
  		clear_cache(route)
  
  	content = (comment.content
  		+ "<p><a href='{0}/app/Form/Comment/{1}' style='font-size: 80%'>{2}</a></p>".format(frappe.utils.get_request_site_address(),
  			comment.name,
  			_("View Comment")))
  
  	# notify creator
  	frappe.sendmail(
  		recipients=frappe.db.get_value('User', doc.owner, 'email') or doc.owner,
  		subject=_('New Comment on {0}: {1}').format(doc.doctype, doc.name),
  		message=content,
  		reference_doctype=doc.doctype,
  		reference_name=doc.name
  	)
  
  	# revert with template if all clear (no backlinks)
  	template = frappe.get_template("templates/includes/comments/comment.html")
  	return template.render({"comment": comment.as_dict()})
  