Task create and update

app/controllers/tasks_controller.rb

@@ -4,21 +4,56 @@ class TasksController < ApplicationController
   before_action :fetch_task, only: %w[show edit update delete]
 
   def index
-    if params[:project]
-      @project = Project.find_by!(code: params[:project])
-      @tasks = @project.tasks
-    else
-      @tasks = Task.all
-    end
+    @project = fetch_project
+    @tasks = if @project
+               @project.tasks
+             else
+               Task.all
+             end
 
     @tasks = @tasks.includes(:project)
   end
 
   def show; end
 
+  def new
+    @form = Tasks::Create.new(project_id: fetch_project&.id)
+  end
+
+  def create
+    @form = Tasks::Create.new(params.expect(task: %i[project_id title description]))
+    if @form.perform
+      redirect_to tasks_path(project: @form.project)
+    else
+      render :new, status: :unprocessable_entity
+    end
+  end
+
+  def edit
+    @form = Tasks::Update.new(id: @task.id, title: @task.title, description: @task.description)
+  end
+
+  def update
+    @form = Tasks::Update.new(params.expect(task: %i[title description]))
+
+    if @form.perform(@task)
+      redirect_to task_path(@task)
+    else
+      render :edit, status: :unprocessable_entity
+    end
+  end
+
+  def delete; end
+
   private
 
+  def fetch_project
+    return nil if params[:project].blank?
+
+    Project.find_by!(code: params[:project])
+  end
+
   def fetch_task
-    @task = Task.find_by_full_number_or_id!(params[:id])
+    @task = Task.includes(:project).find_by_full_number_or_id!(params[:id])
   end
 end

app/models/task.rb

@@ -19,7 +19,7 @@ class Task < ApplicationRecord
   end
 
   def self.find_by_full_number_or_id!(number_or_id)
-    return find!(number_or_id) if number_or_id.is_a?(Numeric) || number_or_id =~ /\A\d+\z/
+    return find(number_or_id) if number_or_id.is_a?(Numeric) || number_or_id =~ /\A\d+\z/
 
     project_code, number = number_or_id.split('-')
     project = Project.find_by!(code: project_code.downcase)

app/services/application_service.rb

@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+class ApplicationService
+  include ActiveModel::Model
+  include ActiveModel::Attributes
+
+  attr_reader :errors
+
+  def perform
+    # Override this
+  end
+
+  private
+
+  def save(model)
+    model.save.tap { @errors = model.errors }
+  end
+end

app/services/tasks/create.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module Tasks
+  class Create < ApplicationService
+    attribute :project_id, :integer
+    attribute :title, :string
+    attribute :description, :string
+
+    validates :project_id, :title, presence: true
+
+    delegate :model_name, to: Task
+
+    attr_reader :project, :task
+
+    def perform
+      @project = Project.find(project_id)
+
+      @task = @project.tasks.build(title:, description:, number: @project.next_task_number)
+      @task.save.tap { @errors = @task.errors }
+    end
+  end
+end

app/services/tasks/update.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module Tasks
+  class Update < ApplicationService
+    attribute :id, :integer
+    attribute :title, :string
+    attribute :description, :string
+
+    validates :title, presence: true
+
+    delegate :model_name, to: Task
+
+    def persisted? = true
+
+    def perform(task)
+      @task = task
+      @id = task.id
+      @task.assign_attributes(title:, description:)
+      save @task
+    end
+  end
+end

app/views/tasks/edit.html.slim

@@ -0,0 +1,13 @@
+h1
+  | Editing task
+  =< @task.full_number
+
+= form_with model: @form do |form|
+  .field
+    = form.label :title
+    = form.text_field :title
+  .field
+    = form.label :description
+    = form.rich_textarea :description
+  .submit
+    = form.submit 'Update task'

app/views/tasks/new.html.slim

@@ -0,0 +1,14 @@
+h1 New task
+
+= form_with model: @form do |form|
+  .field
+    = form.label :project_id
+    = form.select :project_id, Project.order(:name).map { |p| [p.name, p.id] }
+  .field
+    = form.label :title
+    = form.text_field :title
+  .field
+    = form.label :description
+    = form.rich_textarea :description
+  .submit
+    = form.submit 'Create task'