1 files changed, 95 insertions, 0 deletions
diff --git a/app/models/project_services/slack_message.rb b/app/models/project_services/slack_message.rb
new file mode 100644
index 00000000000..b2b8d6fed7a
--- /dev/null
+++ b/app/models/project_services/slack_message.rb
@@ -0,0 +1,95 @@
+require 'slack-notifier'
+
+class SlackMessage
+  def initialize(params)
+    @after = params.fetch(:after)
+    @before = params.fetch(:before)
+    @commits = params.fetch(:commits, [])
+    @project_name = params.fetch(:project_name)
+    @project_url = params.fetch(:project_url)
+    @ref = params.fetch(:ref).gsub('refs/heads/', '')
+    @username = params.fetch(:user_name)
+  end
+
+  def compose
+    format(message)
+  end
+
+  private
+
+  attr_reader :after
+  attr_reader :before
+  attr_reader :commits
+  attr_reader :project_name
+  attr_reader :project_url
+  attr_reader :ref
+  attr_reader :username
+
+  def message
+    if new_branch?
+      new_branch_message
+    elsif removed_branch?
+      removed_branch_message
+    else
+      push_message << commit_messages
+    end
+  end
+
+  def format(string)
+    Slack::Notifier::LinkFormatter.format(string)
+  end
+
+  def new_branch_message
+    "#{username} pushed new branch #{branch_link} to #{project_link}"
+  end
+
+  def removed_branch_message
+    "#{username} removed branch #{ref} from #{project_link}"
+  end
+
+  def push_message
+    "#{username} pushed to branch #{branch_link} of #{project_link} (#{compare_link})"
+  end
+
+  def commit_messages
+    commits.each_with_object('') do |commit, str|
+      str << compose_commit_message(commit)
+    end
+  end
+
+  def compose_commit_message(commit)
+    id = commit.fetch(:id)[0..5]
+    message = commit.fetch(:message)
+    url = commit.fetch(:url)
+
+    "\n - #{message} ([#{id}](#{url}))"
+  end
+
+  def new_branch?
+    before =~ /000000/
+  end
+
+  def removed_branch?
+    after =~ /000000/
+  end
+
+  def branch_url
+    "#{project_url}/commits/#{ref}"
+  end
+
+  def compare_url
+    "#{project_url}/compare/#{before}...#{after}"
+  end
+
+  def branch_link
+    "[#{ref}](#{branch_url})"
+  end
+
+  def project_link
+    "[#{project_name}](#{project_url})"
+  end
+
+  def compare_link
+    "[Compare changes](#{compare_url})"
+  end
+end