calculator

app/assets/javascripts/application.js

@@ -18,4 +18,5 @@
 //= require typeahead
 //= require autosize
 //= require chosen.jquery
+//= require underscore
 //= require_tree .

app/assets/javascripts/calculator.js

@@ -0,0 +1,73 @@
+(function($) {
+
+  function State() {
+    this.input = null;
+    this.outputUnit = null;
+    this.changed = false;
+  }
+
+  State.prototype.setInput = function(value) {
+    if (value != this.input) {
+      this.changed = true;
+      this.input = value;
+    }
+  };
+
+  State.prototype.setOutputUnit = function(value) {
+    if (value != this.outputUnit) {
+      this.changed = true;
+      this.outputUnit = value;
+    }
+  };
+
+  State.prototype.is_changed = function() {
+    return this.changed;
+  };
+
+  State.prototype.reset = function() {
+    this.changed = false;
+  };
+
+  $(document).on("ready page:load", function() {
+
+    var state = new State();
+    var $input = $("#input");
+    var $output = $("#output");
+    var $outputUnit = $("#output_unit");
+
+    var performUpdate = _.debounce(function() {
+      $.getJSON(
+        "/calculator/calculate",
+        {input: $input.val(), output_unit: $outputUnit.val()},
+        function(data) {
+          if (data.errors.input) {
+            $input.closest(".form-group").addClass("has-error");
+          } else {
+            $input.closest(".form-group").removeClass("has-error");
+          }
+
+          if (data.errors.output_unit) {
+            $outputUnit.closest(".form-group").addClass("has-error");
+          } else {
+            $outputUnit.closest(".form-group").removeClass("has-error");
+          }
+
+          $output.val(data.output);
+        }
+      );
+
+    }, 500);
+
+    $input.add($outputUnit).on('change blur keyup', function(evt) {
+      state.setInput($input.val());
+      state.setOutputUnit($outputUnit.val());
+
+      if (state.is_changed()) {
+        performUpdate();
+        state.reset();
+      }
+    });
+
+  });
+
+})(jQuery);

app/controllers/calculator_controller.rb

@@ -0,0 +1,45 @@
+class CalculatorController < ApplicationController
+
+  def index
+
+  end
+
+  def calculate
+    input = params[:input]
+    output_unit = params[:output_unit]
+    parsed_input = nil
+    original_number = nil
+
+    data = {errors: {}, output: ''}
+
+    if input.present?
+
+      begin
+        parsed_input = UnitConversion.parse(input)
+        original_number = parsed_input.value
+      rescue UnitConversion::UnparseableUnitError => e
+        data[:errors][:input] = [e.message]
+      end
+
+      if parsed_input.present? && output_unit.present?
+        begin
+          parsed_input = parsed_input.convert_to output_unit
+        rescue Unitwise::ExpressionError => e
+          data[:errors][:output_unit] = [e.message]
+        end
+      end
+
+      if parsed_input
+        puts parsed_input.value
+        puts parsed_input.unit
+        data[:output] = UnitConversion.auto_unit(UnitConversion.quantity_format(parsed_input.value, original_number), parsed_input.unit.to_s)
+      end
+
+    else
+      data[:errors][:input] = ['Invalid input']
+    end
+
+    render json: data
+  end
+
+end

app/controllers/ingredients_controller.rb

@@ -2,7 +2,7 @@ class IngredientsController < ApplicationController
 
   before_action :set_ingredient, only: [:edit, :update, :destroy]
 
-  before_filter :ensure_valid_user, only: [:new, :edit, :create, :update, :destroy]
+  before_filter :ensure_valid_user, except: [:index]
 
   # GET /ingredients
   # GET /ingredients.json

app/controllers/recipes_controller.rb

@@ -2,7 +2,7 @@ class RecipesController < ApplicationController
 
   before_action :set_recipe, only: [:show, :edit, :update, :destroy, :scale]
 
-  before_filter :ensure_valid_user, only: [:new, :edit, :create, :update, :destroy]
+  before_filter :ensure_valid_user, except: [:show, :scale, :index]
 
   # GET /recipes
   def index
@@ -24,7 +24,6 @@ class RecipesController < ApplicationController
   # GET /recipes/new
   def new
     @recipe = Recipe.new
-    @recipe.recipe_ingredients << RecipeIngredient.new
   end
 
   # GET /recipes/1/edit

app/helpers/application_helper.rb

@@ -8,6 +8,7 @@ module ApplicationHelper
     [
         nav_item('Recipes', recipes_path, 'recipes'),
         nav_item('Ingredients', ingredients_path, 'ingredients'),
+        nav_item('Calculator', calculator_path, 'calculator'),
         nav_item('About', about_path, 'home')
     ]
   end

app/models/unit_conversion.rb

@@ -118,6 +118,7 @@ module UnitConversion
     end
 
     def normalize_unit_names(unit_description)
+      return unit_description.to_sym if UNIT_ALIASES.include?(unit_description.to_sym)
       unit_description.downcase.gsub(/[a-z]+/) do |match|
         UNIT_ALIAS_MAP[match] || match
       end

app/views/calculator/index.html.erb

@@ -0,0 +1,26 @@
+<div class="row">
+  <div class="col-xs-12">
+
+    <div class="page-header">
+      <h1>Calculator</h1>
+    </div>
+
+    <div class="row">
+      <div class="form-group col-xs-12 col-sm-8">
+        <%= label_tag :input, "Input", class: 'control-label' %>
+        <%= text_field_tag :input, nil, class: 'form-control', autofocus: true %>
+      </div>
+      <div class="form-group col-xs-12 col-sm-4">
+        <%= label_tag :output_unit, "Output Unit", class: 'control-label' %>
+        <%= text_field_tag :output_unit, nil, class: 'form-control' %>
+      </div>
+
+      <div class="form-group col-xs-12">
+        <%= label_tag :output, "Output", class: 'control-label' %>
+        <%= text_field_tag :output, nil, class: 'form-control', readonly: true %>
+      </div>
+
+    </div>
+
+  </div>
+</div>

app/views/users/_form.html.erb

@@ -4,7 +4,7 @@
 
   <div class="form-group">
     <%= f.label :username, class: 'control-label' %>
-    <%= f.text_field :username, class: 'form-control' %>
+    <%= f.text_field :username, autofocus: true, class: 'form-control' %>
   </div>
   <div class="form-group">
     <%= f.label :full_name, 'Name', class: 'control-label' %>

app/views/users/login.html.erb

@@ -12,7 +12,7 @@
 
       <div class="form-group">
         <%= label_tag :username, "Username", class: 'control-label' %>
-        <%= text_field_tag :username, nil, class: 'form-control' %>
+        <%= text_field_tag :username, nil, autofocus: true, class: 'form-control' %>
       </div>
 
       <div class="form-group">

config/routes.rb

@@ -28,6 +28,11 @@ Rails.application.routes.draw do
 
   get '/about' => 'home#about', as: :about
 
+  scope '/calculator', controller: :calculator, as: :calculator do
+    get '/' => :index
+    get '/calculate' => :calculate
+  end
+
   root 'recipes#index'
 
 

spec/models/unit_conversion_spec.rb

@@ -21,6 +21,7 @@ RSpec.describe UnitConversion do
       expect(UnitConversion.auto_unit('1/16', 'cup')).to eq ['1', 'tablespoon']
       expect(UnitConversion.auto_unit('1/48', 'cup')).to eq ['1', 'teaspoon']
       expect(UnitConversion.auto_unit('768', 'tsp')).to eq ['1', 'gallon']
+      expect(UnitConversion.auto_unit('6', '[tsp_us]')).to eq ['2', 'tablespoon']
     end
 
     it 'converts standard mass units correctly' do