rails8-memoapp/app/controllers/memos_controller.rb

class MemosController < ApplicationController
  before_action :set_memo, only: %i[edit update destroy]
  before_action :authenticate_user!

  def index
    @q = current_user.memos.ransack(params[:q])
    @memos = @q.result(distinct: true)
               .order(created_at: :desc)
               .page(params[:page])
               .per(4)

    respond_to do |format|
      format.html
      format.turbo_stream
    end
  end

  def new
    @memo = current_user.memos.build
  end

  def edit
    @memo = current_user.memos.find(params[:id])
  end

  def create
    @memo = current_user.memos.build(memo_params)
    respond_to do |format|
      if @memo.save
        format.html { redirect_to memos_path, status: :see_other }
        format.turbo_stream
      else
        format.html { render :new, status: :unprocessable_entity }
        format.turbo_stream { render :new, status: :unprocessable_entity }
      end
    end
  end

  def update
    respond_to do |format|
      if @memo.update(memo_params)
        format.html { redirect_to memos_path, status: :see_other }
        format.turbo_stream { redirect_to memos_path, status: :see_other }
      else
        format.html { render :edit, status: :unprocessable_entity }
        format.turbo_stream { render :edit, status: :unprocessable_entity }
      end
    end
  end

  def destroy
    @memo.destroy
    respond_to do |format|
      format.html { redirect_to memos_path, status: :see_other }
      format.turbo_stream
    end
  end

  private

  def set_memo
    @memo = current_user.memos.find_by(id: params[:id])
    return unless @memo.nil?

    redirect_to memos_path, alert: 'メモが見つかりませんでした'
  end

  def memo_params
    params.require(:memo).permit(:content, :image)
  end
end