# frozen_string_literal: true

# Redmine - project management software
# Copyright (C) 2006-2019  Jean-Philippe Lang
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

require 'roadie'

class Mailer < ActionMailer::Base
	layout 'mailer'
	helper :application
	helper :issues
	helper :custom_fields

	include Redmine::I18n
	include Roadie::Rails::Automatic

	# Overrides ActionMailer::Base#process in order to set the recipient as the current user
	# and his language as the default locale.
	# The first argument of all actions of this Mailer must be a User (the recipient),
	# otherwise an ArgumentError is raised.
	def process(action, *args)
		user = args.first
		raise ArgumentError, "First argument has to be a user, was #{user.inspect}" unless user.is_a?(User)

		initial_user = User.current
		initial_language = ::I18n.locale
		begin
			User.current = user

			lang = find_language(user.language) if user.logged?
			lang ||= Setting.default_language
			set_language_if_valid(lang)

			super(action, *args)
		ensure
			User.current = initial_user
			::I18n.locale = initial_language
		end
	end

	# Default URL options for generating URLs in emails based on host_name and protocol
	# defined in application settings.
	def self.default_url_options
		options = { :protocol => Setting.protocol }
		if Setting.host_name.to_s =~ /\A(https?\:\/\/)?(.+?)(\:(\d+))?(\/.+)?\z/i
			host, port, prefix = $2, $4, $5
			options.merge!({
							   :host => host, :port => port, :script_name => prefix
						   })
		else
			options[:host] = Setting.host_name
		end
		options
	end

	# Builds a mail for notifying user about a new issue
	def issue_add(user, issue)
		redmine_headers 'Project' => issue.project.identifier,
						'Issue-Tracker' => issue.tracker.name,
						'Issue-Id' => issue.id,
						'Issue-Author' => issue.author.login
		redmine_headers 'Issue-Assignee' => issue.assigned_to.login if issue.assigned_to
		message_id issue
		references issue
		@author = issue.author
		@issue = issue
		@user = user
		@issue_url = url_for(:controller => 'issues', :action => 'show', :id => issue)
		subject = "[#{issue.project.name} - #{issue.tracker.name} ##{issue.id}]"
		subject += " (#{issue.status.name})" if Setting.show_status_changes_in_mail_subject?
		subject += " #{issue.subject}"
		mail :to => user,
			 :subject => subject
	end

	# Notifies users about a new issue.
	#
	# Example:
	#   Mailer.deliver_issue_add(issue)
	def self.deliver_issue_add(issue)
		users = issue.notified_users | issue.notified_watchers
		users.each do |user|
			issue_add(user, issue).deliver_later
		end
	end

	# Builds a mail for notifying user about an issue update
	def issue_edit(user, journal)
		issue = journal.journalized
		redmine_headers 'Project' => issue.project.identifier,
						'Issue-Tracker' => issue.tracker.name,
						'Issue-Id' => issue.id,
						'Issue-Author' => issue.author.login
		redmine_headers 'Issue-Assignee' => issue.assigned_to.login if issue.assigned_to
		message_id journal
		references issue
		@author = journal.user
		s = "[#{issue.project.name} - #{issue.tracker.name} ##{issue.id}] "
		s += "(#{issue.status.name}) " if journal.new_value_for('status_id') && Setting.show_status_changes_in_mail_subject?
		s += issue.subject
		@issue = issue
		@user = user
		@journal = journal
		@journal_details = journal.visible_details
		@issue_url = url_for(:controller => 'issues', :action => 'show', :id => issue, :anchor => "change-#{journal.id}")

		mail :to => user,
			 :subject => s
	end

	# Notifies users about an issue update.
	#
	# Example:
	#   Mailer.deliver_issue_edit(journal)
	def self.deliver_issue_edit(journal)
		users = journal.notified_users | journal.notified_watchers
		users.select! do |user|
			journal.notes? || journal.visible_details(user).any?
		end
		users.each do |user|
			issue_edit(user, journal).deliver_later
		end
	end

	# Builds a mail to user about a new document.
	def document_added(user, document, author)
		redmine_headers 'Project' => document.project.identifier
		@author = author
		@document = document
		@user = user
		@document_url = url_for(:controller => 'documents', :action => 'show', :id => document)
		mail :to => user,
			 :subject => "[#{document.project.name}] #{l(:label_document_new)}: #{document.title}"
	end

	# Notifies users that document was created by author
	#
	# Example:
	#   Mailer.deliver_document_added(document, author)
	def self.deliver_document_added(document, author)
		users = document.notified_users
		users.each do |user|
			document_added(user, document, author).deliver_later
		end
	end

	# Builds a mail to user about new attachements.
	def attachments_added(user, attachments)
		container = attachments.first.container
		added_to = ''
		added_to_url = ''
		@author = attachments.first.author
		case container.class.name
			when 'Project'
				added_to_url = url_for(:controller => 'files', :action => 'index', :project_id => container)
				added_to = "#{l(:label_project)}: #{container}"
			when 'Version'
				added_to_url = url_for(:controller => 'files', :action => 'index', :project_id => container.project)
				added_to = "#{l(:label_version)}: #{container.name}"
			when 'Document'
				added_to_url = url_for(:controller => 'documents', :action => 'show', :id => container.id)
				added_to = "#{l(:label_document)}: #{container.title}"
		end
		redmine_headers 'Project' => container.project.identifier
		@attachments = attachments
		@user = user
		@added_to = added_to
		@added_to_url = added_to_url
		mail :to => user,
			 :subject => "[#{container.project.name}] #{l(:label_attachment_new)}"
	end

	# Notifies users about new attachments
	#
	# Example:
	#   Mailer.deliver_attachments_added(attachments)
	def self.deliver_attachments_added(attachments)
		container = attachments.first.container
		case container.class.name
			when 'Project', 'Version'
				users = container.project.notified_users.select { |user| user.allowed_to?(:view_files, container.project) }
			when 'Document'
				users = container.notified_users
		end

		users.each do |user|
			attachments_added(user, attachments).deliver_later
		end
	end

	# Builds a mail to user about a new message.
	def message_posted(user, message)
		redmine_headers 'Project' => message.project.identifier,
						'Topic-Id' => (message.parent_id || message.id)
		@author = message.author
		message_id message
		references message.root
		@message = message
		@user = user
		@message_url = url_for(message.event_url)
		mail :to => user,
			 :subject => "[#{message.board.project.name} - #{message.board.name} - msg#{message.root.id}] #{message.subject}"
	end

	# Notifies users about a new forum message.
	#
	# Example:
	#   Mailer.deliver_message_posted(message)
	def self.deliver_message_posted(message)
		users = message.notified_users
		users |= message.root.notified_watchers
		users |= message.board.notified_watchers

		users.each do |user|
			message_posted(user, message).deliver_later
		end
	end

	# Builds a mail to user about a new wiki content.
	def wiki_content_added(user, wiki_content)
		redmine_headers 'Project' => wiki_content.project.identifier,
						'Wiki-Page-Id' => wiki_content.page.id
		@author = wiki_content.author
		message_id wiki_content
		@wiki_content = wiki_content
		@user = user
		@wiki_content_url = url_for(:controller => 'wiki', :action => 'show',
									:project_id => wiki_content.project,
									:id => wiki_content.page.title)
		mail :to => user,
			 :subject => "[#{wiki_content.project.name}] #{l(:mail_subject_wiki_content_added, :id => wiki_content.page.pretty_title)}"
	end

	# Notifies users about a new wiki content (wiki page added).
	#
	# Example:
	#   Mailer.deliver_wiki_content_added(wiki_content)
	def self.deliver_wiki_content_added(wiki_content)
		users = wiki_content.notified_users | wiki_content.page.wiki.notified_watchers
		users.each do |user|
			wiki_content_added(user, wiki_content).deliver_later
		end
	end

	# Builds a mail to user about an update of the specified wiki content.
	def wiki_content_updated(user, wiki_content)
		redmine_headers 'Project' => wiki_content.project.identifier,
						'Wiki-Page-Id' => wiki_content.page.id
		@author = wiki_content.author
		message_id wiki_content
		@wiki_content = wiki_content
		@user = user
		@wiki_content_url = url_for(:controller => 'wiki', :action => 'show',
									:project_id => wiki_content.project,
									:id => wiki_content.page.title)
		@wiki_diff_url = url_for(:controller => 'wiki', :action => 'diff',
								 :project_id => wiki_content.project, :id => wiki_content.page.title,
								 :version => wiki_content.version)
		mail :to => user,
			 :subject => "[#{wiki_content.project.name}] #{l(:mail_subject_wiki_content_updated, :id => wiki_content.page.pretty_title)}"
	end

	# Notifies users about the update of the specified wiki content
	#
	# Example:
	#   Mailer.deliver_wiki_content_updated(wiki_content)
	def self.deliver_wiki_content_updated(wiki_content)
		users = wiki_content.notified_users
		users |= wiki_content.page.notified_watchers
		users |= wiki_content.page.wiki.notified_watchers

		users.each do |user|
			wiki_content_updated(user, wiki_content).deliver_later
		end
	end

	# Builds a mail to user about his account information.
	def account_information(user, password)
		@user = user
		@password = password
		@login_url = url_for(:controller => 'account', :action => 'login')
		mail :to => user.mail,
			 :subject => l(:mail_subject_register, Setting.app_title)
	end

	# Notifies user about his account information.
	def self.deliver_account_information(user, password)
		account_information(user, password).deliver_later
	end

	# Builds a mail to user about an account activation request.
	def account_activation_request(user, new_user)
		@new_user = new_user
		@url = url_for(:controller => 'users', :action => 'index',
					   :status => User::STATUS_REGISTERED,
					   :sort_key => 'created_on', :sort_order => 'desc')
		mail :to => user,
			 :subject => l(:mail_subject_account_activation_request, Setting.app_title)
	end

	# Notifies admin users that an account activation request needs
	# their approval.
	#
	# Exemple:
	#   Mailer.deliver_account_activation_request(new_user)
	def self.deliver_account_activation_request(new_user)
		# Send the email to all active administrators
		users = User.active.where(:admin => true)
		users.each do |user|
			account_activation_request(user, new_user).deliver_later
		end
	end

	# Builds a mail to notify user that his account was activated.
	def account_activated(user)
		@user = user
		@login_url = url_for(:controller => 'account', :action => 'login')
		mail :to => user.mail,
			 :subject => l(:mail_subject_register, Setting.app_title)
	end

	# Notifies user that his account was activated.
	#
	# Exemple:
	#   Mailer.deliver_account_activated(user)
	def self.deliver_account_activated(user)
		account_activated(user).deliver_later
	end

	# Builds a mail with the password recovery link.
	def lost_password(user, token, recipient = nil)
		recipient ||= user.mail
		@token = token
		@url = url_for(:controller => 'account', :action => 'lost_password', :token => token.value)
		mail :to => recipient,
			 :subject => l(:mail_subject_lost_password, Setting.app_title)
	end

	# Sends an email to user with a password recovery link.
	# The email will be sent to the email address specifiedby recipient if provided.
	#
	# Exemple:
	#   Mailer.deliver_account_activated(user, token)
	#   Mailer.deliver_account_activated(user, token, 'foo@example.net')
	def self.deliver_lost_password(user, token, recipient = nil)
		lost_password(user, token, recipient).deliver_later
	end

	# Notifies user that his password was updated by sender.
	#
	# Exemple:
	#   Mailer.deliver_password_updated(user, sender)
	def self.deliver_password_updated(user, sender)
		# Don't send a notification to the dummy email address when changing the password
		# of the default admin account which is required after the first login
		# TODO: maybe not the best way to handle this
		return if user.admin? && user.login == 'admin' && user.mail == 'admin@example.net'

		deliver_security_notification(user,
									  sender,
									  message: :mail_body_password_updated,
									  title: :button_change_password,
									  url: { controller: 'my', action: 'password' }
		)
	end

	# Builds a mail to user with his account activation link.
	def register(user, token)
		@token = token
		@url = url_for(:controller => 'account', :action => 'activate', :token => token.value)
		mail :to => user.mail,
			 :subject => l(:mail_subject_register, Setting.app_title)
	end

	# Sends an mail to user with his account activation link.
	#
	# Exemple:
	#   Mailer.deliver_register(user, token)
	def self.deliver_register(user, token)
		register(user, token).deliver_later
	end

	# Build a mail to user and the additional recipients given in
	# options[:recipients] about a security related event made by sender.
	#
	# Example:
	#   security_notification(user,
	#     sender,
	#     message: :mail_body_security_notification_add,
	#     field: :field_mail,
	#     value: address
	#   ) => Mail::Message object
	def security_notification(user, sender, options = {})
		@sender = sender
		redmine_headers 'Sender' => sender.login
		@message = l(options[:message],
					 field: (options[:field] && l(options[:field])),
					 value: options[:value]
		)
		@title = options[:title] && l(options[:title])
		@remote_ip = options[:remote_ip] || @sender.remote_ip
		@url = options[:url] && (options[:url].is_a?(Hash) ? url_for(options[:url]) : options[:url])
		redmine_headers 'Url' => @url
		mail :to => [user, *options[:recipients]].uniq,
			 :subject => "[#{Setting.app_title}] #{l(:mail_subject_security_notification)}"
	end

	# Notifies the given users about a security related event made by sender.
	#
	# You can specify additional recipients in options[:recipients]. These will be
	# added to all generated mails for all given users. Usually, you'll want to
	# give only a single user when setting the additional recipients.
	#
	# Example:
	#   Mailer.deliver_security_notification(users,
	#     sender,
	#     message: :mail_body_security_notification_add,
	#     field: :field_mail,
	#     value: address
	#   )
	def self.deliver_security_notification(users, sender, options = {})
		# Symbols cannot be serialized:
		# ActiveJob::SerializationError: Unsupported argument type: Symbol
		options = options.transform_values { |v| v.is_a?(Symbol) ? v.to_s : v }
		# sender's remote_ip would be lost on serialization/deserialization
		# we have to pass it with options
		options[:remote_ip] ||= sender.remote_ip

		Array.wrap(users).each do |user|
			security_notification(user, sender, options).deliver_later
		end
	end

	# Build a mail to user about application settings changes made by sender.
	def settings_updated(user, sender, changes, options = {})
		@sender = sender
		redmine_headers 'Sender' => sender.login
		@changes = changes
		@remote_ip = options[:remote_ip] || @sender.remote_ip
		@url = url_for(controller: 'settings', action: 'index')
		mail :to => user,
			 :subject => "[#{Setting.app_title}] #{l(:mail_subject_security_notification)}"
	end

	# Notifies admins about application settings changes made by sender, where
	# changes is an array of settings names.
	#
	# Exemple:
	#   Mailer.deliver_settings_updated(sender, [:login_required, :self_registration])
	def self.deliver_settings_updated(sender, changes, options = {})
		return unless changes.present?

		# Symbols cannot be serialized:
		# ActiveJob::SerializationError: Unsupported argument type: Symbol
		changes = changes.map(&:to_s)
		# sender's remote_ip would be lost on serialization/deserialization
		# we have to pass it with options
		options[:remote_ip] ||= sender.remote_ip

		users = User.active.where(admin: true).to_a
		users.each do |user|
			settings_updated(user, sender, changes, options).deliver_later
		end
	end

	# Build a test email to user.
	def test_email(user)
		@url = url_for(:controller => 'my')
		mail :to => user,
			 :subject => 'Redbet test'
	end

	# Send a test email to user. Will raise error that may occur during delivery.
	#
	# Exemple:
	#   Mailer.deliver_test_email(user)
	def self.deliver_test_email(user)
		raise_delivery_errors_was = self.raise_delivery_errors
		self.raise_delivery_errors = true
		# Email must be delivered synchronously so we can catch errors
		test_email(user).deliver_now
	ensure
		self.raise_delivery_errors = raise_delivery_errors_was
	end

	# Builds a reminder mail to user about issues that are due in the next days.
	def reminder(user, issues, days)
		@issues = issues
		@days = days
		@issues_url = url_for(:controller => 'issues', :action => 'index',
							  :set_filter => 1, :assigned_to_id => 'me',
							  :sort => 'due_date:asc')
		query = IssueQuery.new(:name => '_')
		query.add_filter('assigned_to_id', '=', ['me'])
		@open_issues_count = query.issue_count
		mail :to => user,
			 :subject => l(:mail_subject_reminder, :count => issues.size, :days => days)
	end

	# Sends reminders to issue assignees
	# Available options:
	# * :days     => how many days in the future to remind about (defaults to 7)
	# * :tracker  => id of tracker for filtering issues (defaults to all trackers)
	# * :project  => id or identifier of project to process (defaults to all projects)
	# * :users    => array of user/group ids who should be reminded
	# * :version  => name of target version for filtering issues (defaults to none)
	def self.reminders(options = {})
		days = options[:days] || 7
		project = options[:project] ? Project.find(options[:project]) : nil
		tracker = options[:tracker] ? Tracker.find(options[:tracker]) : nil
		target_version_id = options[:version] ? Version.named(options[:version]).pluck(:id) : nil
		if options[:version] && target_version_id.blank?
			raise ActiveRecord::RecordNotFound.new("Couldn't find Version named #{options[:version]}")
		end
		user_ids = options[:users]

		scope = Issue.open.where("#{Issue.table_name}.assigned_to_id IS NOT NULL" +
									 " AND #{Project.table_name}.status = #{Project::STATUS_ACTIVE}" +
									 " AND #{Issue.table_name}.due_date <= ?", days.day.from_now.to_date
		)
		scope = scope.where(:assigned_to_id => user_ids) if user_ids.present?
		scope = scope.where(:project_id => project.id) if project
		scope = scope.where(:fixed_version_id => target_version_id) if target_version_id.present?
		scope = scope.where(:tracker_id => tracker.id) if tracker
		issues_by_assignee = scope.includes(:status, :assigned_to, :project, :tracker).
			group_by(&:assigned_to)
		issues_by_assignee.keys.each do |assignee|
			if assignee.is_a?(Group)
				assignee.users.each do |user|
					issues_by_assignee[user] ||= []
					issues_by_assignee[user] += issues_by_assignee[assignee]
				end
			end
		end

		issues_by_assignee.each do |assignee, issues|
			if assignee.is_a?(User) && assignee.active? && issues.present?
				visible_issues = issues.select { |i| i.visible?(assignee) }
				visible_issues.sort! { |a, b| (a.due_date <=> b.due_date).nonzero? || (a.id <=> b.id) }
				reminder(assignee, visible_issues, days).deliver_later if visible_issues.present?
			end
		end
	end

	# Activates/desactivates email deliveries during +block+
	def self.with_deliveries(enabled = true, &block)
		was_enabled = ActionMailer::Base.perform_deliveries
		ActionMailer::Base.perform_deliveries = !!enabled
		yield
	ensure
		ActionMailer::Base.perform_deliveries = was_enabled
	end

	# Execute the given block with inline sending of emails if the default Async
	# queue is used for the mailer. See the Rails guide:
	# Using the asynchronous queue from a Rake task will generally not work because
	# Rake will likely end, causing the in-process thread pool to be deleted, before
	# any/all of the .deliver_later emails are processed
	def self.with_synched_deliveries(&block)
		adapter = ActionMailer::DeliveryJob.queue_adapter
		if adapter.is_a?(ActiveJob::QueueAdapters::AsyncAdapter)
			ActionMailer::DeliveryJob.queue_adapter = ActiveJob::QueueAdapters::InlineAdapter.new
		end
		yield
	ensure
		ActionMailer::DeliveryJob.queue_adapter = adapter
	end

	def mail(headers = {}, &block)
		# Add a display name to the From field if Setting.mail_from does not
		# include it
		begin
			mail_from = Mail::Address.new(Setting.mail_from)
			if mail_from.display_name.blank? && mail_from.comments.blank?
				mail_from.display_name =
					@author&.logged? ? @author.name : Setting.app_title
			end
			from = mail_from.format
			list_id = "<#{mail_from.address.to_s.tr('@', '.')}>"
		rescue Mail::Field::IncompleteParseError
			# Use Setting.mail_from as it is if Mail::Address cannot parse it
			# (probably the emission address is not RFC compliant)
			from = Setting.mail_from.to_s
			list_id = "<#{from.tr('@', '.')}>"
		end

		headers.reverse_merge! 'X-Mailer' => 'Redmine',
							   'X-Redmine-Host' => Setting.host_name,
							   'X-Redmine-Site' => Setting.app_title,
							   'X-Auto-Response-Suppress' => 'All',
							   'Auto-Submitted' => 'auto-generated',
							   'From' => from,
							   'List-Id' => list_id

		# Replaces users with their email addresses
		[:to, :cc, :bcc].each do |key|
			if headers[key].present?
				headers[key] = self.class.email_addresses(headers[key])
			end
		end

		# Removes the author from the recipients and cc
		# if the author does not want to receive notifications
		# about what the author do
		if @author&.logged? && @author.pref.no_self_notified
			addresses = @author.mails
			headers[:to] -= addresses if headers[:to].is_a?(Array)
			headers[:cc] -= addresses if headers[:cc].is_a?(Array)
		end

		if @author&.logged?
			redmine_headers 'Sender' => @author.login
		end

		# Blind carbon copy recipients
		if Setting.bcc_recipients?
			headers[:bcc] = [headers[:to], headers[:cc]].flatten.uniq.reject(&:blank?)
			headers[:to] = nil
			headers[:cc] = nil
		end

		if @message_id_object
			headers[:message_id] = "<#{self.class.message_id_for(@message_id_object, @user)}>"
		end
		if @references_objects
			headers[:references] = @references_objects.collect { |o| "<#{self.class.references_for(o, @user)}>" }.join(' ')
		end

		if block_given?
			super headers, &block
		else
			super headers do |format|
				format.text
				format.html unless Setting.plain_text_mail?
			end
		end
	end

	def self.deliver_mail(mail)
		return false if mail.to.blank? && mail.cc.blank? && mail.bcc.blank?
		begin
			# Log errors when raise_delivery_errors is set to false, Rails does not
			mail.raise_delivery_errors = true
			super
		rescue => e
			if ActionMailer::Base.raise_delivery_errors
				raise e
			else
				Rails.logger.error "Email delivery error: #{e.message}"
			end
		end
	end

	# Returns an array of email addresses to notify by
	# replacing users in arg with their notified email addresses
	#
	# Example:
	#   Mailer.email_addresses(users)
	#   => ["foo@example.net", "bar@example.net"]
	def self.email_addresses(arg)
		arr = Array.wrap(arg)
		mails = arr.reject { |a| a.is_a? Principal }
		users = arr - mails
		if users.any?
			mails += EmailAddress.
				where(:user_id => users.map(&:id)).
				where("is_default = ? OR notify = ?", true, true).
				pluck(:address)
		end
		mails
	end

	private

	# Appends a Redmine header field (name is prepended with 'X-Redmine-')
	def redmine_headers(h)
		h.each { |k, v| headers["X-Redmine-#{k}"] = v.to_s }
	end

	# Singleton class method is public
	class << self
		def token_for(object, user)
			timestamp = object.send(object.respond_to?(:created_on) ? :created_on : :updated_on)
			hash = [
				"redmine",
				"#{object.class.name.demodulize.underscore}-#{object.id}",
				timestamp.utc.strftime("%Y%m%d%H%M%S")
			]
			hash << user.id if user
			host = Setting.mail_from.to_s.strip.gsub(%r{^.*@|>}, '')
			host = "#{::Socket.gethostname}.redmine" if host.empty?
			"#{hash.join('.')}@#{host}"
		end

		# Returns a Message-Id for the given object
		def message_id_for(object, user)
			token_for(object, user)
		end

		# Returns a uniq token for a given object referenced by all notifications
		# related to this object
		def references_for(object, user)
			token_for(object, user)
		end
	end

	def message_id(object)
		@message_id_object = object
	end

	def references(object)
		@references_objects ||= []
		@references_objects << object
	end
end
