Add minimal volunteer tracking (resolves #29)

Gemfile

@@ -33,6 +33,7 @@ gem 'jbuilder', '~> 2.5'
 # Reduces boot times through caching; required in config/boot.rb
 gem 'bootsnap', '>= 1.1.0', require: false
 gem "bulma-rails", "~> 0.7.4"
+gem 'lodash-rails'
 gem 'postcodes_io'
 gem 'jquery-rails'
 gem 'xkpassword'

Gemfile.lock

@@ -126,6 +126,8 @@ GEM
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
       ruby_dep (~> 1.2)
+    lodash-rails (4.17.14)
+      railties (>= 3.1)
     loofah (2.3.1)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
@@ -273,6 +275,7 @@ DEPENDENCIES
   jbuilder (~> 2.5)
   jquery-rails
   listen (>= 3.0.5, < 3.2)
+  lodash-rails
   pg
   postcodes_io
   puma (~> 3.11)

app/assets/javascripts/application.js

@@ -13,5 +13,6 @@
 //= require rails-ujs
 //= require activestorage
 //= require turbolinks
+//= require lodash
 //= require_tree .
 //= require cookies_eu

app/assets/javascripts/volunteer_control_panel.js

@@ -0,0 +1,47 @@
+const debouncedUpdaters = {};
+
+function increaseVolunteersControl(formIdentifier, updateUrl) {
+  volunteersControl(formIdentifier, updateUrl, function(value) {
+    return value + 1;
+  });
+}
+
+function decreaseVolunteersControl(formIdentifier, updateUrl) {
+  volunteersControl(formIdentifier, updateUrl, function(value) {
+    return value - 1;
+  });
+}
+
+function volunteersControl(formIdentifier, updateUrl, updateCallback) {
+  const valueElement = elementFor(formIdentifier, 'value');
+  const newValue = updateCallback(+valueElement.innerHTML);
+
+  if (newValue >= 0) {
+    valueElement.innerHTML = newValue;
+
+    let updateServer = debouncedUpdaters[formIdentifier];
+    if (!updateServer) {
+      updateServer = _.debounce(function() {
+        const savingElement = elementFor(formIdentifier, 'saving');
+        savingElement.classList.remove('is-invisible');
+
+        const data = {count: valueElement.innerHTML};
+        function onSuccess() {
+          savingElement.classList.add('is-invisible')
+        }
+
+        // XXX Add better error handling
+        $.post(updateUrl, data, onSuccess);
+      }, 500);
+
+      debouncedUpdaters[formIdentifier] = updateServer;
+    }
+
+    updateServer();
+  }
+}
+
+function elementFor(formIdentifier, type) {
+  const controlValueId = `${formIdentifier}-${type}`;
+  return document.getElementById(controlValueId);
+}

app/controllers/committee_rooms_controller.rb

@@ -30,8 +30,28 @@ def create
     redirect_to new_work_space_committee_room_path(work_space)
   end
 
+  def canvassers
+    volunteers_observation_action(CanvassersObservation)
+  end
+
+  def cars
+    volunteers_observation_action(CarsObservation)
+  end
+
   private
 
+  def volunteers_observation_action(observation_class)
+    committee_room = CommitteeRoom.find(params[:committee_room_id])
+    # XXX More ad-hoc authorization, should improve.
+    return if committee_room.work_space != find_work_space
+
+    observation_class.create!(
+      committee_room: committee_room,
+      count: params[:count],
+      user: @current_user
+    )
+  end
+
   def committee_room_params
     params.require(:committee_room).permit(:address, :organiser_name)
   end

app/models/committee_room.rb

@@ -6,4 +6,18 @@ class CommitteeRoom < ApplicationRecord
 
   validates_presence_of :address
   validates_presence_of :organiser_name
+
+  def last_canvassers_observation
+    last_observation_for(canvassers_observations)
+  end
+
+  def last_cars_observation
+    last_observation_for(cars_observations)
+  end
+
+  private
+
+  def last_observation_for(observations)
+    observations.max_by(&:created_at) || UnobservedCommitteeRoomObservation.new
+  end
 end

app/models/unobserved_committee_room_observation.rb

@@ -0,0 +1,7 @@
+
+# Null object for CommitteeRoomObservations.
+class UnobservedCommitteeRoomObservation
+  def count
+    0
+  end
+end

app/views/work_spaces/_committee_room_info.html.erb

@@ -10,8 +10,23 @@
         <%= committee_room.organiser_name %>
       </p>
 
-      <%= render 'volunteer_control_panel', text: 'Canvassers: 30' %>
-      <%= render 'volunteer_control_panel', text: 'Cars: 2' %>
+      <%= render 'volunteer_control_panel',
+        identifier: "canvassers-#{committee_room.id}",
+        text: 'Canvassers',
+        count: committee_room.last_canvassers_observation.count,
+        update_count_url: work_space_committee_room_canvassers_path(
+          committee_room.work_space, committee_room
+        )
+      %>
+
+      <%= render 'volunteer_control_panel',
+        identifier: "cars-#{committee_room.id}",
+        text: 'Cars',
+        count: committee_room.last_cars_observation.count,
+        update_count_url: work_space_committee_room_cars_path(
+          committee_room.work_space, committee_room
+        )
+      %>
     <% else %>
 
       <p class="is-size-6 is-italic">

app/views/work_spaces/_volunteer_control_panel.html.erb

@@ -1,7 +1,7 @@
 
 <div class="field has-addons is-marginless">
   <p class="control">
-    <button class="button">
+    <button class="button" onclick="decreaseVolunteersControl('<%= identifier %>', '<%= update_count_url %>')">
       <span class="icon">
         <i class="fa fa-minus"></i>
       </span>
@@ -10,12 +10,19 @@
 
   <p class="control">
     <div class="fake-button is-fullwidth">
-      <span><%= text %></span>
+      <span id="<%= identifier %>-saving" class="is-invisible">
+        <span class="fa fa-spinner fa-spin"></span>
+      </span>
+      &nbsp;
+      <span><%= text %>:
+        <%# XXX Make count also editable directly, if needed %>
+        <span id="<%= identifier %>-value"><%= count %></span>
+      </span>
     </div>
   </p>
 
   <p class="control">
-    <button class="button">
+    <button class="button" onclick="increaseVolunteersControl('<%= identifier %>', '<%= update_count_url %>')">
       <span class="icon">
         <i class="fa fa-plus"></i>
       </span>

config/routes.rb

@@ -15,7 +15,10 @@
       end
     end
 
-    resources :committee_rooms, path: 'committee-room', except: :index
+    resources :committee_rooms, path: 'committee-room', except: :index do
+      post :canvassers
+      post :cars
+    end
   end
 
   resources :users, only: :update