Model Creation Progress:
- [ ] Step 1: Define requirements (attributes, validations, associations)
- [ ] Step 2: Create model test (RED)
- [ ] Step 3: Create fixtures
- [ ] Step 4: Run test (should fail - no model/table)
- [ ] Step 5: Generate migration
- [ ] Step 6: Run migration
- [ ] Step 7: Create model file (empty)
- [ ] Step 8: Run test (should fail - no validations)
- [ ] Step 9: Add validations and associations
- [ ] Step 10: Run test (GREEN)

## Model: [ModelName]

### Table: [table_name]

### Attributes
| Name | Type | Constraints | Default |
|------|------|-------------|---------|
| name | string | required, unique | - |
| email | string | required, unique, email format | - |
| status | integer | enum | 0 (pending) |
| organization_id | bigint | foreign key | - |

### Associations
- belongs_to :organization
- has_many :posts, dependent: :destroy
- has_one :profile, dependent: :destroy

### Validations
- name: presence, uniqueness, length(max: 100)
- email: presence, uniqueness, format(email)
- status: inclusion in enum values

### Scopes
- active: status = active
- recent: ordered by created_at desc
- by_organization(org): where organization_id = org.id

### Instance Methods
- full_name: combines first_name and last_name
- active?: checks if status is active

### Callbacks
- before_save :normalize_email
- after_create :send_welcome_email

# frozen_string_literal: true

require "test_helper"

class ModelNameTest < ActiveSupport::TestCase
  # === Associations ===
  test "belongs to organization" do
    model = model_names(:one)
    assert_respond_to model, :organization
    assert_instance_of Organization, model.organization
  end

  test "has many posts" do
    model = model_names(:one)
    assert_respond_to model, :posts
  end

  # === Validations ===
  test "requires name" do
    model = ModelName.new(name: nil)
    assert_not model.valid?
    assert_includes model.errors[:name], "can't be blank"
  end

  test "requires unique email (case insensitive)" do
    existing = model_names(:one)
    model = ModelName.new(email: existing.email.upcase)
    assert_not model.valid?
    assert_includes model.errors[:email], "has already been taken"
  end

  test "validates name length max 100" do
    model = ModelName.new(name: "a" * 101)
    assert_not model.valid?
    assert model.errors[:name].any? { |e| e.include?("too long") }
  end

  # === Scopes ===
  test ".active returns only active records" do
    active_record = model_names(:active_one)
    inactive_record = model_names(:inactive_one)

    results = ModelName.active
    assert_includes results, active_record
    assert_not_includes results, inactive_record
  end

  # === Instance Methods ===
  test "#full_name returns combined name" do
    model = ModelName.new(first_name: "John", last_name: "Doe")
    assert_equal "John Doe", model.full_name
  end
end

# test/fixtures/model_names.yml
one:
  name: "Test Model One"
  email: "model-one@example.com"
  status: 0
  organization: one

two:
  name: "Test Model Two"
  email: "model-two@example.com"
  status: 0
  organization: one

active_one:
  name: "Active Model"
  email: "active@example.com"
  status: 1
  organization: one

inactive_one:
  name: "Inactive Model"
  email: "inactive@example.com"
  status: 2
  organization: one

bin/rails test test/models/model_name_test.rb

bin/rails generate migration CreateModelNames \
  name:string \
  email:string:uniq \
  status:integer \
  organization:references

# db/migrate/YYYYMMDDHHMMSS_create_model_names.rb
class CreateModelNames < ActiveRecord::Migration[8.0]
  def change
    create_table :model_names do |t|
      t.string :name, null: false
      t.string :email, null: false
      t.integer :status, null: false, default: 0
      t.references :organization, null: false, foreign_key: true

      t.timestamps
    end

    add_index :model_names, :email, unique: true
    add_index :model_names, :status
  end
end

bin/rails db:migrate

bin/rails db:migrate:status

# frozen_string_literal: true

class ModelName < ApplicationRecord
end

bin/rails test test/models/model_name_test.rb

# frozen_string_literal: true

class ModelName < ApplicationRecord
  # === Associations ===
  belongs_to :organization
  has_many :posts, dependent: :destroy

  # === Enums ===
  enum :status, { pending: 0, active: 1, suspended: 2 }

  # === Validations ===
  validates :name, presence: true,
                   uniqueness: true,
                   length: { maximum: 100 }
  validates :email, presence: true,
                    uniqueness: { case_sensitive: false },
                    format: { with: URI::MailTo::EMAIL_REGEXP }

  # === Scopes ===
  scope :active, -> { where(status: :active) }
  scope :recent, -> { order(created_at: :desc) }

  # === Instance Methods ===
  def full_name
    "#{first_name} #{last_name}".strip
  end
end

bin/rails test test/models/model_name_test.rb

enum :status, { draft: 0, published: 1, archived: 2 }
validates :status, inclusion: { in: statuses.keys }

belongs_to :commentable, polymorphic: true

belongs_to :organization, counter_cache: true
# Add: organization.posts_count column

scope :active, -> { where(deleted_at: nil) }
scope :deleted, -> { where.not(deleted_at: nil) }

def soft_delete
  update(deleted_at: Time.current)
end

normalizes :email, with: -> { _1.strip.downcase }
normalizes :phone, with: -> { _1.gsub(/\D/, "") }