<?php
declare(strict_types=1);

use PHPUnit\Framework\TestCase;

/**
 * Composite indexes declared on a group reach its existing flat table.
 *
 * The table already exists with data (its schema hash is unchanged), so the
 * index is added in place rather than through a table rebuild.
 */
class GroupCompositeIndexTest extends TestCase {

	private const TABLE = 'wp_itest_wpdo_post_ci_core';

	public static function setUpBeforeClass(): void {
		$base = WPDO_PLUGIN_DIR;
		foreach ( array(
			'includes/adapters/interface-entity-adapter.php',
			'includes/engine/class-tmdo-schema-manager.php',
			'includes/engine/class-tmdo-entity-registry.php',
			'includes/adapters/class-tmdo-adapter-post.php',
		) as $file ) {
			require_once $base . $file;
		}
	}

	protected function setUp(): void {
		global $wpdb;
		$wpdb->query( 'DROP TABLE IF EXISTS `' . self::TABLE . '`' );
		$wpdb->query( 'CREATE TABLE `' . self::TABLE . '` ( id BIGINT NOT NULL AUTO_INCREMENT, post_id BIGINT NOT NULL, ci_flag BIGINT(20) DEFAULT NULL, ci_price DECIMAL(18,6) DEFAULT NULL, PRIMARY KEY (id), UNIQUE KEY uk_entity (post_id) ) ENGINE=InnoDB' );
		$wpdb->query( 'INSERT INTO `' . self::TABLE . '` (post_id, ci_flag, ci_price) VALUES (1, 1, 10), (2, 0, 20)' );
		$GLOBALS['_wp_options'] = array();

		$ref = new ReflectionProperty( WPDO_Schema_Manager::class, 'table_exists_cache' );
		$ref->setAccessible( true );
		$ref->setValue( null, array() );

		WPDO_Entity_Registry::init();
		WPDO_Entity_Registry::register_adapter( 'post', new WPDO_Adapter_Post() );
		WPDO_Entity_Registry::register_group(
			'post',
			'ci_core',
			array(
				array( 'key' => 'ci_flag', 'type' => 'integer' ),
				array( 'key' => 'ci_price', 'type' => 'decimal' ),
			),
			array( 'indexes' => array( 'flag_price' => array( 'ci_flag', 'ci_price' ) ) )
		);
	}

	protected function tearDown(): void {
		global $wpdb;
		$wpdb->query( 'DROP TABLE IF EXISTS `' . self::TABLE . '`' );
		WPDO_Entity_Registry::init();
	}

	/** @return array<string, string[]> index name → ordered columns */
	private function indexes(): array {
		global $wpdb;
		$out = array();
		foreach ( (array) $wpdb->get_results( 'SHOW INDEX FROM `' . self::TABLE . '`', ARRAY_A ) as $row ) {
			$out[ $row['Key_name'] ][ (int) $row['Seq_in_index'] - 1 ] = $row['Column_name'];
		}
		return $out;
	}

	public function test_missing_composite_index_is_added_to_the_existing_table(): void {
		TMDO_Schema_Manager::ensure_group_indexes( 'post', 'ci_core' );

		$this->assertSame( array( 'ci_flag', 'ci_price' ), $this->indexes()['cidx_flag_price'] ?? null );
		global $wpdb;
		$this->assertSame( '2', $wpdb->get_var( 'SELECT COUNT(*) FROM `' . self::TABLE . '`' ), 'data untouched' );
	}

	public function test_applied_definition_is_remembered_so_later_requests_skip_the_check(): void {
		TMDO_Schema_Manager::ensure_group_indexes( 'post', 'ci_core' );
		global $wpdb;
		$wpdb->query( 'ALTER TABLE `' . self::TABLE . '` DROP INDEX `cidx_flag_price`' );

		TMDO_Schema_Manager::ensure_group_indexes( 'post', 'ci_core' );

		$this->assertArrayNotHasKey( 'cidx_flag_price', $this->indexes(), 'same definition → no SHOW INDEX / ALTER' );
		$this->assertArrayHasKey( 'post/ci_core', get_option( TMDO_Schema_Manager::INDEXES_OPTION ) );
	}

	public function test_group_without_indexes_is_left_alone(): void {
		WPDO_Entity_Registry::init();
		WPDO_Entity_Registry::register_adapter( 'post', new WPDO_Adapter_Post() );
		WPDO_Entity_Registry::register_group( 'post', 'ci_core', array( array( 'key' => 'ci_flag', 'type' => 'integer' ) ) );

		TMDO_Schema_Manager::ensure_group_indexes( 'post', 'ci_core' );

		$this->assertSame( array( 'PRIMARY', 'uk_entity' ), array_keys( $this->indexes() ) );
		$this->assertFalse( get_option( TMDO_Schema_Manager::INDEXES_OPTION ) );
	}
}