<?php
declare(strict_types=1);

use PHPUnit\Framework\TestCase;

if ( ! defined( 'WPDO_CACHE_GROUP' ) ) {
	define( 'WPDO_CACHE_GROUP', 'wpdo' );
}

if ( ! function_exists( 'current_filter' ) ) {
	/**
	 * Stub: returns $GLOBALS['_wp_current_filter'] so tests can set the simulated
	 * filter context before calling WPDO_Hook_Bus::intercept_update/delete.
	 */
	function current_filter(): string {
		return $GLOBALS['_wp_current_filter'] ?? '';
	}
}

/**
 * Integration test: WPDO_Hook_Bus intercept paths (P1-8 coverage).
 *
 * Verifies the three core interception methods (intercept_update, intercept_get,
 * intercept_delete) against real MariaDB, covering:
 *   - aeav_only: flat write + EAV short-circuit (returns true)
 *   - dual_write: flat write + EAV passthrough (returns null)
 *   - disabled: full passthrough, no flat write
 *   - unregistered key: passthrough
 *   - direct_read: bypass-filter read path
 *   - cleanup_entity: row deletion on entity removal
 *
 * current_filter() is stubbed via $GLOBALS['_wp_current_filter'] — tests set
 * this before calling intercept_update/delete to simulate the WP filter context
 * that would normally be provided by the metadata filter pipeline.
 */
class HookBusIntegrationTest extends TestCase {

	private const TYPE         = 'user';
	private const GROUP        = 'core_profile';
	private const FLAT_TABLE   = 'wp_itest_wpdo_user_core_profile';
	private const ERRORS_TABLE = 'wp_itest_wpdo_errors';

	// ── Fixture lifecycle ─────────────────────────────────────────────────────

	public static function setUpBeforeClass(): void {
		global $wpdb;

		$base = WPDO_PLUGIN_DIR;
		foreach ( array(
			'includes/adapters/interface-entity-adapter.php',
			'includes/engine/class-tmdo-type-caster.php',
			'includes/engine/class-tmdo-schema-manager.php',
			'includes/engine/class-tmdo-entity-registry.php',
			'includes/engine/class-tmdo-mode-manager.php',
			'includes/engine/class-tmdo-cache-orchestrator.php',
			'includes/adapters/class-tmdo-adapter-user.php',
			'includes/integrations/class-tmdo-member-fields.php',
			'includes/engine/class-tmdo-hook-bus.php',
		) as $file ) {
			require_once $base . $file;
		}

		// Clear stale Schema_Manager cache entries for tables we manage.
		// We only remove the specific entry rather than replacing the entire cache
		// to avoid corrupting cached state that other test classes depend on.
		$ref   = new ReflectionClass( WPDO_Schema_Manager::class );
		$cache = $ref->getProperty( 'table_exists_cache' );
		$cache->setAccessible( true );
		$existing = $cache->getValue( null );
		unset( $existing[ self::FLAT_TABLE ] );
		$cache->setValue( null, $existing );

		// Errors table (required by WPDO_Logger).
		$wpdb->query( 'DROP TABLE IF EXISTS `' . self::ERRORS_TABLE . '`' );
		$wpdb->query(
			'CREATE TABLE `' . self::ERRORS_TABLE . '` (
				`id`         bigint(20) unsigned NOT NULL AUTO_INCREMENT,
				`module`     varchar(100)        NOT NULL DEFAULT \'\',
				`zone`       varchar(20)         NOT NULL DEFAULT \'\',
				`hook`       varchar(255)        NOT NULL DEFAULT \'\',
				`message`    text                NOT NULL,
				`context`    longtext,
				`created_at` datetime            NOT NULL DEFAULT \'0000-00-00 00:00:00\',
				PRIMARY KEY (`id`)
			) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4'
		);

		// Flat table for user core_profile.
		$wpdb->query( 'DROP TABLE IF EXISTS `' . self::FLAT_TABLE . '`' );
		$wpdb->query(
			'CREATE TABLE `' . self::FLAT_TABLE . '` (
				`id`          bigint(20) unsigned NOT NULL AUTO_INCREMENT,
				`user_id`     bigint(20)          NOT NULL,
				`nickname`    varchar(255)        DEFAULT NULL,
				`first_name`  varchar(255)        DEFAULT NULL,
				`last_name`   varchar(255)        DEFAULT NULL,
				`description` text                DEFAULT NULL,
				`created_at`  datetime            NOT NULL DEFAULT CURRENT_TIMESTAMP,
				`updated_at`  datetime            NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
				PRIMARY KEY (`id`),
				UNIQUE KEY `uk_user` (`user_id`)
			) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4'
		);

		// Mark table as known-good in Schema_Manager cache (add, don't replace).
		$existing2                     = $cache->getValue( null ) ?? array();
		$existing2[ self::FLAT_TABLE ] = true;
		$cache->setValue( null, $existing2 );

		// Register adapter + all user field groups (direct call — add_action is a no-op
		// in the integration test environment, so ::register() would not fire).
		WPDO_Entity_Registry::init();
		WPDO_Entity_Registry::register_adapter( self::TYPE, new WPDO_Adapter_User() );
		WPDO_Member_Fields::register_entity_fields();
	}

	public static function tearDownAfterClass(): void {
		global $wpdb;
		$wpdb->query( 'DROP TABLE IF EXISTS `' . self::FLAT_TABLE . '`' );
		$wpdb->query( 'DROP TABLE IF EXISTS `' . self::ERRORS_TABLE . '`' );

		// Reset Mode_Manager + Entity_Registry so this test class doesn't leak
		// user mode state into subsequent integration test classes.
		$mref  = new ReflectionClass( WPDO_Mode_Manager::class );
		$mcache = $mref->getProperty( 'cache' );
		$mcache->setAccessible( true );
		$mcache->setValue( null, null );

		WPDO_Entity_Registry::init();

		// Clear Schema_Manager table_exists_cache entirely so that the `false`
		// entries written by cleanup_entity (for non-existent group tables) don't
		// trick subsequent test classes into thinking those tables don't exist after
		// they create them.
		$sref   = new ReflectionClass( WPDO_Schema_Manager::class );
		$scache = $sref->getProperty( 'table_exists_cache' );
		$scache->setAccessible( true );
		$scache->setValue( null, array() );
	}

	protected function setUp(): void {
		global $wpdb;
		$wpdb->query( 'TRUNCATE TABLE `' . self::FLAT_TABLE . '`' );

		$GLOBALS['_wp_options']        = array();
		$GLOBALS['_wp_cache']          = array();
		$GLOBALS['_wp_current_filter'] = '';

		// Default: user mode = aeav_only (most tests use this).
		self::set_user_mode( WPDO_Mode_Manager::MODE_AEAV_ONLY );

		// Clear Cache_Orchestrator L1.
		$ref = new ReflectionClass( WPDO_Cache_Orchestrator::class );
		$l1  = $ref->getProperty( 'l1_cache' );
		$l1->setAccessible( true );
		$l1->setValue( null, array() );
	}

	/**
	 * Inject user mode into Mode_Manager's static cache (bypasses wp_options
	 * and Cache_Orchestrator dependency of Mode_Manager::set()).
	 */
	private static function set_user_mode( string $mode ): void {
		$ref   = new ReflectionClass( WPDO_Mode_Manager::class );
		$cache = $ref->getProperty( 'cache' );
		$cache->setAccessible( true );
		$cache->setValue( null, array(
			'user'    => $mode,
			'post'    => 'disabled',
			'term'    => 'dual_write',
			'comment' => 'dual_write',
		) );
	}

	// ── Helpers ───────────────────────────────────────────────────────────────

	private function read_flat_first_name( int $user_id ): ?string {
		global $wpdb;
		return $wpdb->get_var(
			$wpdb->prepare(
				'SELECT `first_name` FROM `' . self::FLAT_TABLE . '` WHERE `user_id` = %d',
				$user_id
			)
		);
	}

	// ── Tests: intercept_update ───────────────────────────────────────────────

	public function test_update_writes_to_flat_in_aeav_only_mode(): void {
		$GLOBALS['_wp_current_filter'] = 'update_user_metadata';

		WPDO_Hook_Bus::intercept_update( null, 1, 'first_name', 'Alice', '' );

		$this->assertSame( 'Alice', $this->read_flat_first_name( 1 ) );
	}

	public function test_update_returns_true_in_aeav_only_mode(): void {
		$GLOBALS['_wp_current_filter'] = 'update_user_metadata';

		$result = WPDO_Hook_Bus::intercept_update( null, 2, 'first_name', 'Bob', '' );

		$this->assertTrue( $result, 'aeav_only must return true to short-circuit EAV write' );
	}

	public function test_update_writes_flat_and_returns_null_in_dual_write_mode(): void {
		self::set_user_mode( WPDO_Mode_Manager::MODE_DUAL_WRITE );
		$GLOBALS['_wp_current_filter'] = 'update_user_metadata';

		$result = WPDO_Hook_Bus::intercept_update( null, 3, 'first_name', 'Carol', '' );

		$this->assertSame( 'Carol', $this->read_flat_first_name( 3 ) );
		$this->assertNull( $result, 'dual_write must return null so WP continues to write EAV' );
	}

	public function test_update_passthrough_for_unregistered_key(): void {
		$GLOBALS['_wp_current_filter'] = 'update_user_metadata';

		$sentinel = new stdClass();
		$result   = WPDO_Hook_Bus::intercept_update( $sentinel, 4, '_nonexistent_key_xyz', 'x', '' );

		$this->assertSame( $sentinel, $result, 'unregistered key must return $check unchanged' );
		$this->assertNull( $this->read_flat_first_name( 4 ), 'unregistered key must not write flat table' );
	}

	public function test_update_passthrough_in_disabled_mode(): void {
		self::set_user_mode( WPDO_Mode_Manager::MODE_DISABLED );
		$GLOBALS['_wp_current_filter'] = 'update_user_metadata';

		$result = WPDO_Hook_Bus::intercept_update( null, 5, 'first_name', 'Dave', '' );

		$this->assertNull( $result, 'disabled mode must return $check unchanged' );
		$this->assertNull( $this->read_flat_first_name( 5 ), 'disabled mode must not write flat table' );
	}

	public function test_update_passthrough_when_filter_context_unresolvable(): void {
		$GLOBALS['_wp_current_filter'] = ''; // no active filter

		$sentinel = new stdClass();
		$result   = WPDO_Hook_Bus::intercept_update( $sentinel, 6, 'first_name', 'Eve', '' );

		$this->assertSame( $sentinel, $result, 'unknown filter context must return $check unchanged' );
	}

	// ── Tests: intercept_get ─────────────────────────────────────────────────

	public function test_get_reads_from_flat_in_aeav_only_mode(): void {
		// Seed the flat table directly.
		global $wpdb;
		$wpdb->query(
			$wpdb->prepare(
				'INSERT INTO `' . self::FLAT_TABLE . '` (`user_id`, `first_name`) VALUES (%d, %s)',
				10,
				'Frank'
			)
		);

		// intercept_get accepts $meta_type as 5th arg — bypasses current_filter().
		$result = WPDO_Hook_Bus::intercept_get( null, 10, 'first_name', true, 'user' );

		$this->assertSame( array( 'Frank' ), $result, 'intercept_get must return [value] array in aeav_only mode' );
	}

	public function test_get_passthrough_in_dual_write_mode(): void {
		self::set_user_mode( WPDO_Mode_Manager::MODE_DUAL_WRITE );

		$result = WPDO_Hook_Bus::intercept_get( null, 11, 'first_name', true, 'user' );

		$this->assertNull( $result, 'dual_write does not read from flat — must return $check' );
	}

	public function test_get_returns_empty_string_when_column_is_null(): void {
		global $wpdb;
		$wpdb->query(
			$wpdb->prepare(
				'INSERT INTO `' . self::FLAT_TABLE . '` (`user_id`, `first_name`) VALUES (%d, NULL)',
				12
			)
		);

		$result = WPDO_Hook_Bus::intercept_get( null, 12, 'first_name', true, 'user' );

		$this->assertSame( '', $result );
	}

	// ── Tests: intercept_delete ───────────────────────────────────────────────

	public function test_delete_clears_column_to_null_in_aeav_only_mode(): void {
		global $wpdb;
		$wpdb->query(
			$wpdb->prepare(
				'INSERT INTO `' . self::FLAT_TABLE . '` (`user_id`, `first_name`) VALUES (%d, %s)',
				20,
				'Grace'
			)
		);

		$GLOBALS['_wp_current_filter'] = 'delete_user_metadata';

		WPDO_Hook_Bus::intercept_delete( null, 20, 'first_name', '', false );

		$this->assertNull( $this->read_flat_first_name( 20 ), 'delete must set column to NULL (not drop row)' );
	}

	public function test_delete_returns_true_in_aeav_only_mode(): void {
		global $wpdb;
		$wpdb->query(
			$wpdb->prepare(
				'INSERT INTO `' . self::FLAT_TABLE . '` (`user_id`, `first_name`) VALUES (%d, %s)',
				21,
				'Hank'
			)
		);

		$GLOBALS['_wp_current_filter'] = 'delete_user_metadata';

		$result = WPDO_Hook_Bus::intercept_delete( null, 21, 'first_name', '', false );

		$this->assertTrue( $result, 'aeav_only delete must return true to short-circuit EAV delete' );
	}

	// ── Tests: direct_read ───────────────────────────────────────────────────

	public function test_direct_read_returns_written_value(): void {
		$GLOBALS['_wp_current_filter'] = 'update_user_metadata';
		WPDO_Hook_Bus::intercept_update( null, 30, 'first_name', 'Ivan', '' );

		// Flush cache so direct_read goes to DB.
		$ref = new ReflectionClass( WPDO_Cache_Orchestrator::class );
		$l1  = $ref->getProperty( 'l1_cache' );
		$l1->setAccessible( true );
		$l1->setValue( null, array() );
		$GLOBALS['_wp_cache'] = array();

		$value = WPDO_Hook_Bus::direct_read( 'user', 30, 'first_name' );

		$this->assertSame( 'Ivan', $value );
	}

	public function test_direct_read_returns_null_for_unknown_key(): void {
		$value = WPDO_Hook_Bus::direct_read( 'user', 31, '_nonexistent_key_xyz' );

		$this->assertNull( $value );
	}

	// ── Tests: cleanup_entity ────────────────────────────────────────────────

	public function test_cleanup_entity_removes_flat_rows(): void {
		global $wpdb;
		$wpdb->query(
			$wpdb->prepare(
				'INSERT INTO `' . self::FLAT_TABLE . '` (`user_id`, `first_name`) VALUES (%d, %s)',
				40,
				'Judy'
			)
		);

		WPDO_Hook_Bus::cleanup_entity( 'user', 40 );

		$count = (int) $wpdb->get_var(
			$wpdb->prepare(
				'SELECT COUNT(*) FROM `' . self::FLAT_TABLE . '` WHERE `user_id` = %d',
				40
			)
		);
		$this->assertSame( 0, $count, 'cleanup_entity must delete all flat rows for the entity' );
	}
}