<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class CreateTablesTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('tables', function (Blueprint $table) {
            $table->increments('id');
            $table->timestamps();
            $table->unsignedInteger('owner_id');
            $table->unsignedInteger('ancestor_id')->index()->nullable();
            $table->unsignedInteger('revision_id')->index(); // active revision
            $table->string('name')->index(); // indexable
            $table->string('title')->index(); // indexable
            $table->text('description')->nullable();
            $table->text('license')->nullable();
            $table->text('origin')->nullable();

            $table->foreign('owner_id')->references('id')->on('users')
                ->onDelete('restrict'); // user deleting their account deletes owned tables
            // we block it with RESTRICT to ensure tables are deleted manually

            $table->foreign('revision_id')->references('id')->on('revisions')
                ->onDelete('restrict');

            $table->foreign('ancestor_id')->references('id')->on('tables')
                ->onDelete('set null'); // fork parent deletion must NOT delete child tables
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('tables');
    }
}