Add Slack Username registration feature

lib/redmine_slack/listener.rb

@@ -1,6 +1,11 @@
 require 'httpclient'
 
 class SlackListener < Redmine::Hook::Listener
+
+	def initialize
+		@slack_username_custom_field = UserCustomField.find_by_name("Slack Username")
+	end
+
 	def controller_issues_new_after_save(context={})
 		issue = context[:issue]
 
@@ -10,7 +15,8 @@ def controller_issues_new_after_save(context={})
 		return unless channel and url
 		return if issue.is_private?
 
-		msg = "[#{escape issue.project}] #{escape issue.author} created <#{object_url issue}|#{escape issue}>#{mentions issue.description}"
+		mentions = build_mentions(issue.assigned_to, issue.description, issue.project.identifier)
+		msg = "[#{escape issue.project}] #{escape issue.author} created <#{object_url issue}|#{escape issue}>#{mentions}"
 
 		attachment = {}
 		attachment[:text] = escape issue.description if issue.description
@@ -48,7 +54,9 @@ def controller_issues_edit_after_save(context={})
 		return if issue.is_private?
 		return if journal.private_notes?
 
-		msg = "[#{escape issue.project}] #{escape journal.user.to_s} updated <#{object_url issue}|#{escape issue}>#{mentions journal.notes}"
+		assignee_user = get_assignee_user journal
+		mentions = build_mentions(assignee_user, journal.notes, issue.project.identifier)
+		msg = "[#{escape issue.project}] #{escape journal.user.to_s} updated <#{object_url issue}#change-#{journal.id}|#{escape issue}>#{mentions}"
 
 		attachment = {}
 		attachment[:text] = escape journal.notes if journal.notes
@@ -265,18 +273,85 @@ def detail_to_field(detail)
 		result
 	end
 
-	def mentions text
-		names = extract_usernames text
-		names.present? ? "\nTo: " + names.join(', ') : nil
+	def to_slack_usernames(usernames, project_id)
+		return [] if usernames.empty?
+
+		slack_usernames = usernames.map { |username| find_slack_username(username, project_id) }
+		slack_usernames.select { |n| n.present? }
+	end
+
+	def find_slack_username(redmine_user, project_id)
+		return nil if redmine_user.nil?
+
+		if redmine_user.is_a? User
+			user = redmine_user
+		else
+			user = User.find_by_login(redmine_user)
+		end
+
+		if user.present?
+			val = user.custom_value_for(@slack_username_custom_field).value rescue nil
+			if val.nil?
+				return val
+			end
+
+			result = nil
+			slack_usernames = val.split(/\s?,\s*/)
+			slack_usernames.each { |n|
+				if n.include? ':'
+					proj_id, slack_username = n.split(':')
+					if project_id == proj_id
+						if slack_username != '-'
+							result = slack_username
+						else
+							result = nil
+						end
+						break
+					end
+				elsif n != '-'
+					result = n
+				end
+			}
+			result
+		end
 	end
 
 	def extract_usernames text = ''
+		# Extracts the @xxxxx from the given text and returns a list of usernames (only xxxxx parts)
+
 		if text.nil?
 			text = ''
 		end
 
-		# slack usernames may only contain lowercase letters, numbers,
-		# dashes and underscores and must start with a letter or number.
-		text.scan(/@[a-z0-9][a-z0-9_\-]*/).uniq
+		text.scan(/@[a-z0-9][a-z0-9_\-.]*/).uniq.each do |username|
+			# Remove the leading @
+			username.slice!(0)
+		end
+	end
+
+	def get_assignee_user(journal)
+		assignee_detail = journal.details.find do |detail|
+			detail.prop_key.to_s.sub('_id', '') == 'assigned_to'
+		end
+		if assignee_detail.present?
+			User.find(assignee_detail.value) rescue nil
+		end
+	end
+
+	def build_mentions(assignee_user, text, project_id)
+		# Get the assignee's Redmine User instance
+		assignee_slack_username = find_slack_username(assignee_user, project_id)
+
+		# Retrieve the mentioned Redmine usernames from the given text
+		mentioned_usernames = extract_usernames text
+		slack_usernames = to_slack_usernames(mentioned_usernames, project_id)
+
+		if assignee_slack_username.present?
+			slack_usernames << assignee_slack_username
+		end
+
+		# Slack usernames to be mentioned
+		slack_usernames = slack_usernames.uniq.map { |name| '@' + name }
+		slack_usernames.present? ? "\n" + slack_usernames.join(' ') : nil
 	end
 end