Feature/creating calculators constructor

app/controllers/account/calculators_controller.rb

@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 class Account::CalculatorsController < Account::BaseController
-  before_action :calculator, only: [:edit, :update, :destroy]
   load_and_authorize_resource
 
   def index
@@ -10,11 +9,16 @@ def index
   end
 
   def show
-    # TODO: fill it
+    @calculator = resource
+  end
+
+  def new
+    @products = products_collection
   end
 
   def edit
-    collect_fields_for_form
+    @calculator = resource
+    @products   = products_collection
   end
 
   def create
@@ -23,22 +27,26 @@ def create
     if @calculator.save
       redirect_to account_calculators_path, notice: t("notifications.calculator_created")
     else
+      @products = products_collection
+
       render :new, status: :unprocessable_entity
     end
   end
 
   def update
+    @calculator = resource
+
     if updater
-      redirect_to edit_account_calculator_path(slug: @calculator), notice: t("notifications.calculator_updated")
+      redirect_to account_calculators_path, notice: t("notifications.calculator_updated")
     else
-      collect_fields_for_form
+      @products = products_collection
 
       render :edit, status: :unprocessable_entity
     end
   end
 
   def destroy
-    @calculator.destroy
+    resource.destroy
 
     redirect_to account_calculators_path, notice: t("notifications.calculator_deleted"), status: :see_other
   end
@@ -49,31 +57,12 @@ def collection
     Calculator.ordered_by_name
   end
 
-  def calculator
-    @calculator = Calculator.friendly.find(params[:slug])
-  end
-
-  def collect_fields_for_form
-    @form_fields      = collect_fields_for_kind("form")
-    @parameter_fields = collect_fields_for_kind("parameter")
-    @result_fields    = collect_fields_for_kind("result")
-  end
-
-  def collect_fields_for_kind(kind)
-    @calculator
-      .fields
-      .select { |field| field.kind == kind }
-      .sort_by { |field| field.created_at || Time.zone.now }
+  def resource
+    collection.friendly.find(params[:slug])
   end
 
   def calculator_params
-    params.require(:calculator).permit(
-      :name, :id, :slug, :preferable,
-      fields_attributes: [
-        :id, :selector, :label, :name, :value, :unit, :from, :to, :type, :kind,
-        :_destroy
-      ]
-    )
+    params.require(:calculator).permit(:name, :slug, :product_id)
   end
 
   def updater
@@ -82,4 +71,8 @@ def updater
       @calculator.update(calculator_params)
     end
   end
+
+  def products_collection
+    Product.ordered_by_title
+  end
 end

app/controllers/account/categories_controller.rb

@@ -40,10 +40,9 @@ def update
   end
 
   def destroy
-    @category = resource
-    @category.destroy
+    resource.destroy
 
-    redirect_to account_categories_path, notice: t("notifications.category_deleted")
+    redirect_to account_categories_path, notice: t("notifications.category_deleted"), status: :see_other
   end
 
   private

app/controllers/account/products_controller.rb

@@ -68,7 +68,7 @@ def category_collection
   end
 
   def product_params
-    params.require(:product).permit(:title, prices_attributes: [:id,
+    params.require(:product).permit(:title, :default_usage_per_day, prices_attributes: [:id,
       :sum, :category_id, :_destroy])
   end
 end

app/controllers/api/v1/calculators_controller.rb

@@ -1,13 +1,33 @@
 # frozen_string_literal: true
 
 class Api::V1::CalculatorsController < ApplicationController
-  VALUES = [
-    { name: "bought_diapers", result: 8956 },
-    { name: "money_spent", result: 7841 },
-    { name: "garbage_created", result: 342 }
-  ].freeze
-
-  def compute
-    render json: { result: VALUES }
+  def calculate
+    @calculator_form = CalculatorForm.new(calculator_params)
+
+    if @calculator_form.valid?
+      result = Calculators::CalculateService.new(product_resource, calculator_params).calculate
+
+      render json: result.to_json, status: :ok
+    else
+      render json: { error: @calculator_form.errors.full_messages.join(", ") }, status: :unprocessable_entity
+    end
+  end
+
+  private
+
+  def collection
+    Calculator.ordered_by_name
+  end
+
+  def resource
+    collection.friendly.find(params[:slug])
+  end
+
+  def calculator_params
+    params.permit(:period, :price_id)
+  end
+
+  def product_resource
+    Product.find(resource.product_id)
   end
 end

app/controllers/api/v1/diaper_calculators_controller.rb

@@ -2,16 +2,16 @@
 
 class Api::V1::DiaperCalculatorsController < ApplicationController
   def calculate
-    @validation = CalculatorValidator.new(params)
+    @form = DiaperCalculatorForm.new(calculator_params)
 
-    if @validation.valid?
+    if @form.valid?
       calc_service         = Calculators::DiaperUsageService.new(params[:childs_years], params[:childs_months], set_category_id)
       calc_service.calculate
       calculator_decorator = CalculatorDecorator.new(calc_service.result)
 
       render json: calculator_decorator.to_json, status: :ok
     else
-      render json: { error: @validation.error }, status: :unprocessable_entity
+      render json: { error: @form.errors.full_messages.join(", ") }, status: :unprocessable_entity
     end
   end
 
@@ -20,4 +20,8 @@ def calculate
   def set_category_id
     params[:category_id].presence || Category.preferable.first.id
   end
+
+  def calculator_params
+    params.permit(:childs_years, :childs_months)
+  end
 end

app/helpers/calculators_helper.rb

@@ -46,4 +46,12 @@ def old_calculator_items
       { image: "money_to_spent.png", data_target: "moneyWillBeSpent", text: t(".money_will_be_spent") },
       { image: "money_spent.png", data_target: "moneySpent", text: t(".money_spent") }]
   end
+
+  def use_period
+    ["day", "week", "month", "year"].map { |period| [I18n.t("calculators.date.#{period}"), period] }
+  end
+
+  def product_prices(calculator)
+    calculator.product.prices.map { |price| [price.category.name, price.id] }
+  end
 end

app/javascript/controllers/calculate_controller.js

@@ -0,0 +1,41 @@
+import { Controller } from "@hotwired/stimulus";
+import { FetchRequest } from "@rails/request.js";
+import { toastUtils } from "helpers/toast_helper";
+
+export default class extends Controller {
+  static targets = ["period", "priceCategory"];
+  static outlets = ["calculationresults"];
+  static values = {
+    url: {
+      type: String,
+      default: "en/api/v1/calculators",
+    },
+  };
+
+  submit(e) {
+    e.preventDefault();
+
+    let formData = {
+      period: this.periodTarget.value,
+      price_id: this.priceCategoryTarget.value
+    };
+
+    const request = new FetchRequest("POST", this.urlValue, {
+      responseKind: "json",
+      body: JSON.stringify(formData),
+    });
+
+    this.sendRequest(request);
+  }
+
+  async sendRequest(request) {
+    const response = await request.perform();
+    const result = await response.json;
+
+    if (response.ok) {
+      this.calculationresultsOutlet.showResults(result);
+    } else if (response.statusCode == 422) {
+      toastUtils.showToast(result.error, "error");
+    }
+  }
+}

app/javascript/controllers/calculationresults_controller.js

@@ -0,0 +1,13 @@
+import { Controller } from "@hotwired/stimulus";
+
+export default class extends Controller {
+  static targets = [
+    "moneySpentResult",
+    "itemsUsedResult",
+  ];
+
+  showResults(data) {
+    this.moneySpentResultTarget.innerHTML = data.moneySpent;
+    this.itemsUsedResultTarget.innerHTML = data.itemsUsed;
+  }
+}

app/models/calculator.rb

@@ -28,6 +28,8 @@ class Calculator < ApplicationRecord
 
   has_many :fields, dependent: :destroy
 
+  belongs_to :product
+
   accepts_nested_attributes_for :fields, allow_destroy: true
 
   validates :name, presence: true

app/models/calculator_form.rb

@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+class CalculatorForm
+  include ActiveModel::Model
+
+  attr_accessor :period, :product_category, :price_id
+
+  validates :period, presence: true
+  validates :price_id, presence: true
+end

app/models/diaper_calculator_form.rb

@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+class DiaperCalculatorForm
+  include ActiveModel::Model
+
+  attr_accessor :childs_years, :childs_months
+
+  validate :validate_child_age
+
+  private
+
+  def validate_child_age
+    if childs_years.blank? && childs_months.blank?
+      errors.add(:base, I18n.t("calculators.errors.year_and_month_error_msg"))
+    elsif childs_years.blank?
+      errors.add(:base, I18n.t("calculators.errors.year_error_msg"))
+    elsif childs_months.blank?
+      errors.add(:base, I18n.t("calculators.errors.month_error_msg"))
+    end
+  end
+end

app/models/product.rb

@@ -19,8 +19,7 @@
 class Product < ApplicationRecord
   DIAPER = "diaper"
 
-  scope :ordered_by_title, -> { order(:title) }
-
+  has_one :calculator, dependent: :destroy
   has_many :prices, as: :priceable, dependent: :destroy
   has_many :categories_by_prices, through: :prices, source: :category
 
@@ -30,6 +29,9 @@ class Product < ApplicationRecord
             uniqueness: true,
             format: { with: /\A[a-zA-Zа-яієїґ'А-ЯІЄЇҐ0-9\-\s]+\z/ },
             if: -> { title.present? }
+  validates :default_usage_per_day, numericality: { greater_than: 0 }
+
+  scope :ordered_by_title, -> { order(:title) }
 
   accepts_nested_attributes_for :prices, reject_if: :blank_prices, allow_destroy: true
 

app/services/calculators/calculate_service.rb

@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+class Calculators::CalculateService
+  attr_accessor :product, :period, :items_used, :money_spent, :params
+
+  DAYS = {
+    "day" => 1,
+    "week" => 7,
+    "month" => 30.5,
+    "year" => 365
+  }.freeze
+
+  def initialize(product, params)
+    @product     = product
+    @period      = DAYS[params[:period]]
+    @items_used  = 0
+    @money_spent = 0
+    @params      = params
+  end
+
+  def calculate
+    money_spent = (product.default_usage_per_day * selected_price * period).to_i
+    items_used  = (product.default_usage_per_day * period).to_i
+
+    {
+      moneySpent: money_spent,
+      itemsUsed: items_used
+    }
+  end
+
+  private
+
+  def selected_price
+    product.prices.find(params[:price_id]).sum
+  end
+end