<?php

declare(strict_types=1);

use Phinx\Migration\AbstractMigration;

/**
 * Initial schema: folders mirroring the managed library tree.
 *
 * Folders form a recursive tree structure where each folder has an optional
 * parent folder. The root folder has parent_id = NULL. The path is stored
 * as a materialized absolute path from the library root for efficient queries.
 */
final class CreateFolders extends AbstractMigration
{
    public function change(): void
    {
        $this->table('folders', ['id' => 'id', 'primary_key' => 'id'])
            ->addColumn('parent_id', 'integer', ['null' => true, 'signed' => false])
            ->addColumn('name', 'string', ['limit' => 255])
            ->addColumn('path', 'text', ['null' => false])
            ->addColumn('added_at', 'timestamp', ['default' => 'CURRENT_TIMESTAMP', 'timezone' => true])
            ->addForeignKey('parent_id', 'folders', 'id', ['delete' => 'CASCADE', 'update' => 'NO_ACTION'])
            ->addIndex(['parent_id', 'name'], ['unique' => true, 'name' => 'idx_folders_parent_name'])
            ->addIndex(['path'], ['unique' => true, 'name' => 'idx_folders_path'])
            ->create();

        // Root folder entry (will be created by application on first run)
        // Application ensures root folder exists with path = '/' and parent_id = NULL
    }
}