From 757a9b274e6bc4d500ce3acb84b02b35f19b93f0 Mon Sep 17 00:00:00 2001
From: Dominik Klein <dk@zammad.com>
Date: Mon, 23 May 2022 12:27:43 +0200
Subject: [PATCH] Fixes #4095 - Trigger autocomplete when clicking the "Tags"
 field also without a search term.

---
 .overcommit.yml                                      |  9 +++++++--
 .../javascripts/app/controllers/widget/tag.coffee    |  2 +-
 app/controllers/tags_controller.rb                   | 12 +++++++++++-
 app/models/tag/item.rb                               |  4 ++++
 spec/requests/tag_spec.rb                            | 12 ++++++++++++
 5 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/.overcommit.yml b/.overcommit.yml
index ec20b597c..8c6e18a53 100644
--- a/.overcommit.yml
+++ b/.overcommit.yml
@@ -15,10 +15,15 @@ PreCommit:
     on_warn: fail
   CoffeeLint:
     # .coffeelint/rules/* not supported in YAML, specify all rules separately.
-    flags: ['--reporter=csv', '--rules', './.coffeelint/rules/detect_translatable_string.coffee']
+    flags:
+      [
+        '--reporter=csv',
+        '--rules',
+        './.coffeelint/rules/detect_translatable_string.coffee',
+      ]
     enabled: true
     on_warn: fail
-    exclude: public/assets/chat/**/*
+    exclude: 'public/assets/chat/**/*'
   CustomScript:
     enabled: true
     description: 'Check if translation catalog is up-to-date'
diff --git a/app/assets/javascripts/app/controllers/widget/tag.coffee b/app/assets/javascripts/app/controllers/widget/tag.coffee
index c3e528172..38d1f39d6 100644
--- a/app/assets/javascripts/app/controllers/widget/tag.coffee
+++ b/app/assets/javascripts/app/controllers/widget/tag.coffee
@@ -57,7 +57,7 @@ class App.WidgetTag extends App.Controller
     source = "#{App.Config.get('api_path')}/tag_search"
     @$('.js-newTagInput').autocomplete(
       source: source
-      minLength: 1
+      minLength: 0
       response: (e, ui) =>
         return if !ui
         return if !ui.content
diff --git a/app/controllers/tags_controller.rb b/app/controllers/tags_controller.rb
index aaf3962cb..0284769e0 100644
--- a/app/controllers/tags_controller.rb
+++ b/app/controllers/tags_controller.rb
@@ -6,7 +6,8 @@ class TagsController < ApplicationController
 
   # GET /api/v1/tag_search?term=abc
   def search
-    list = Tag::Item.where('name_downcase LIKE ?', "%#{params[:term].strip.downcase}%").order(name: :asc).limit(params[:limit] || 10)
+    list = get_tag_list(params[:term], params[:limit] || 10)
+
     results = []
     list.each do |item|
       result = {
@@ -95,4 +96,13 @@ class TagsController < ApplicationController
     render json: {}
   end
 
+  private
+
+  def get_tag_list(term, limit)
+    if term.blank?
+      return Tag::Item.left_outer_joins(:tags).group(:id).order('COUNT(tags.tag_item_id) DESC, name ASC').limit(limit)
+    end
+
+    Tag::Item.where('name_downcase LIKE ?', "%#{term.strip.downcase}%").order(name: :asc).limit(limit)
+  end
 end
diff --git a/app/models/tag/item.rb b/app/models/tag/item.rb
index 9686956e2..c45bafa80 100644
--- a/app/models/tag/item.rb
+++ b/app/models/tag/item.rb
@@ -4,6 +4,10 @@ class Tag::Item < ApplicationModel
   validates   :name, presence: true
   before_save :fill_namedowncase
 
+  has_many :tags, foreign_key: 'tag_item_id',
+                  inverse_of:  :tag_item,
+                  dependent:   :destroy
+
 =begin
 
 lookup by name and create tag item
diff --git a/spec/requests/tag_spec.rb b/spec/requests/tag_spec.rb
index 52866f87d..fd1deb72f 100644
--- a/spec/requests/tag_spec.rb
+++ b/spec/requests/tag_spec.rb
@@ -100,6 +100,18 @@ RSpec.describe Tag, type: :request do
         include_examples 'no tag found using', search_term: '1foobar'
         include_examples 'no tag found using', search_term: 'foobar2'
       end
+
+      context 'without search term' do
+        before do
+          create_list(:tag, 2, tag_item: tags.last)
+          create_list(:tag, 1, tag_item: tags.first)
+        end
+
+        it 'most used is on first place without search term' do
+          get '/api/v1/tag_search', params: { term: '' }
+          expect(json_response.first['value']).to eq(tags.last.name)
+        end
+      end
     end
   end
 end