<?php
declare(strict_types=1);

use PHPUnit\Framework\TestCase;

/**
 * Integration test: WPDO_Post_Query_Router (v2.10.1).
 *
 * Verifies meta_query rewriting when post mode is reads_from_flat (i.e.
 * shadow_read or aeav_only). The router strips clauses targeting registered
 * Entity Registry keys, JOINs the corresponding flat table, and appends
 * WHERE conditions in SQL.
 *
 * 🔒 Frozen contract:
 *   - mode=disabled    → router pass-through (zero modification)
 *   - mode=dual_write  → router pass-through (wp_postmeta still source-of-truth)
 *   - mode=shadow_read → router rewrites (flat is read-replica candidate)
 *   - mode=aeav_only   → router rewrites (flat is source-of-truth)
 */
class PostQueryRouterTest extends TestCase {

	public static function setUpBeforeClass(): void {
		$plugin_dir = WPDO_PLUGIN_DIR;
		foreach ( array(
			'includes/adapters/interface-entity-adapter.php',
			'includes/engine/class-tmdo-entity-registry.php',
			'includes/engine/class-tmdo-mode-manager.php',
			'includes/engine/class-tmdo-schema-manager.php',
			'includes/adapters/class-tmdo-adapter-post.php',
			'includes/integrations/class-tmdo-post-fields.php',
			'includes/query/class-tmdo-post-query-router.php',
		) as $rel ) {
			$file = $plugin_dir . $rel;
			if ( file_exists( $file ) ) {
				require_once $file;
			}
		}

		WPDO_Entity_Registry::init();
		WPDO_Entity_Registry::register_adapter( 'post', new WPDO_Adapter_Post() );
		WPDO_Post_Fields::register_entity_fields();
		tmdo_test_register_wc_product_group();
	}

	public static function tearDownAfterClass(): void {
		$ref   = new ReflectionClass( WPDO_Mode_Manager::class );
		$cache = $ref->getProperty( 'cache' );
		$cache->setAccessible( true );
		$cache->setValue( null, null );
		WPDO_Entity_Registry::init();
	}

	private function set_post_mode( string $mode ): void {
		$ref   = new ReflectionClass( WPDO_Mode_Manager::class );
		$cache = $ref->getProperty( 'cache' );
		$cache->setAccessible( true );
		$cache->setValue( null, array(
			'post'    => $mode,
			'user'    => 'aeav_only',
			'term'    => 'dual_write',
			'comment' => 'dual_write',
		) );
	}

	private function make_query( array $vars ): WP_Query {
		$q = new WP_Query();
		foreach ( $vars as $k => $v ) {
			$q->set( $k, $v );
		}
		return $q;
	}

	// ── pre_get_posts gate (mode-aware) ───────────────────────────────────────

	public function test_pass_through_when_mode_disabled(): void {
		$this->set_post_mode( 'disabled' );

		$router = new WPDO_Post_Query_Router();
		$query  = $this->make_query( array(
			'post_type'  => 'product',
			'meta_query' => array(
				array( 'key' => '_price', 'value' => '50', 'compare' => '>=', 'type' => 'NUMERIC' ),
			),
		) );
		$original = $query->get( 'meta_query' );

		$router->pre_get_posts( $query );

		$this->assertSame(
			$original,
			$query->get( 'meta_query' ),
			'mode=disabled: meta_query must be untouched.'
		);
		$this->assertSame( '', $query->get( 'wpdo_post_clauses' ) );
	}

	public function test_pass_through_when_mode_dual_write(): void {
		$this->set_post_mode( 'dual_write' );

		$router = new WPDO_Post_Query_Router();
		$query  = $this->make_query( array(
			'post_type'  => 'product',
			'meta_query' => array(
				array( 'key' => '_price', 'value' => '50', 'compare' => '>=', 'type' => 'NUMERIC' ),
			),
		) );
		$original = $query->get( 'meta_query' );

		$router->pre_get_posts( $query );

		$this->assertSame(
			$original,
			$query->get( 'meta_query' ),
			'mode=dual_write: wp_postmeta is still source-of-truth, no rewrite.'
		);
	}

	// ── pre_get_posts rewrite (mode=aeav_only) ───────────────────────────────

	public function test_rewrites_meta_query_when_mode_aeav_only(): void {
		$this->set_post_mode( 'aeav_only' );

		$router = new WPDO_Post_Query_Router();
		$query  = $this->make_query( array(
			'post_type'  => 'product',
			'meta_query' => array(
				array( 'key' => '_price', 'value' => '50', 'compare' => '>=', 'type' => 'NUMERIC' ),
			),
		) );

		$router->pre_get_posts( $query );

		// Original meta_query stripped of registered keys.
		$remaining = $query->get( 'meta_query' );
		$this->assertEmpty(
			$remaining,
			'aeav_only: registered keys removed from meta_query.'
		);

		// Routed clauses captured under wpdo_post_clauses query var.
		$routed = $query->get( 'wpdo_post_clauses' );
		$this->assertIsArray( $routed );
		$this->assertNotEmpty( $routed );
	}

	public function test_keeps_unmanaged_keys_in_meta_query(): void {
		$this->set_post_mode( 'aeav_only' );

		$router = new WPDO_Post_Query_Router();
		$query  = $this->make_query( array(
			'post_type'  => 'product',
			'meta_query' => array(
				array( 'key' => '_price', 'value' => '50', 'compare' => '>=', 'type' => 'NUMERIC' ),
				array( 'key' => 'unmanaged_attr', 'value' => 'x' ),
			),
		) );

		$router->pre_get_posts( $query );

		$remaining = $query->get( 'meta_query' );
		$this->assertCount( 1, $remaining );
		// Original index preserved (k=1 since k=0 was the routed _price clause).
		$first_clause = reset( $remaining );
		$this->assertSame(
			'unmanaged_attr',
			$first_clause['key'],
			'Unmanaged key remains in meta_query (Hook Bus pass-through).'
		);
	}

	public function test_skips_admin_requests(): void {
		$this->set_post_mode( 'aeav_only' );

		$prev_admin = $GLOBALS['_wp_is_admin'] ?? false;
		$GLOBALS['_wp_is_admin'] = true;

		$router = new WPDO_Post_Query_Router();
		$query  = $this->make_query( array(
			'post_type'  => 'product',
			'meta_query' => array(
				array( 'key' => '_price', 'value' => '50', 'compare' => '>=', 'type' => 'NUMERIC' ),
			),
		) );
		$original = $query->get( 'meta_query' );

		$router->pre_get_posts( $query );

		$this->assertSame(
			$original,
			$query->get( 'meta_query' ),
			'is_admin requests should not be rewritten.'
		);

		$GLOBALS['_wp_is_admin'] = $prev_admin;
	}

	// ── posts_join / posts_where (SQL emission) ──────────────────────────────

	public function test_posts_join_emits_left_join_for_each_routed_post_type(): void {
		$this->set_post_mode( 'aeav_only' );

		$router = new WPDO_Post_Query_Router();
		$query  = $this->make_query( array(
			'post_type'         => 'product',
			'meta_query'        => array(
				array( 'key' => '_price', 'value' => '50', 'type' => 'NUMERIC' ),
			),
			'wpdo_post_clauses' => array(),
		) );

		$router->pre_get_posts( $query );
		$join = $router->posts_join( '', $query );

		$this->assertStringContainsString( 'LEFT JOIN', $join );
		$this->assertStringContainsString( 'wpdo_post_wc_product', $join );
	}

	public function test_posts_join_joins_every_routed_group(): void {
		$this->set_post_mode( 'aeav_only' );

		$router = new WPDO_Post_Query_Router();
		$query  = $this->make_query( array(
			'post_type'  => 'product',
			'meta_query' => array(
				array( 'key' => '_price', 'value' => '50', 'compare' => '>=', 'type' => 'NUMERIC' ),
				array( 'key' => '_thumbnail_id', 'compare' => 'EXISTS' ),
			),
		) );

		$router->pre_get_posts( $query );
		$join  = $router->posts_join( '', $query );
		$where = $router->posts_where( '', $query );

		$this->assertStringContainsString( 'wpdo_post_wc_product', $join );
		$this->assertStringContainsString( 'wpdo_post_wp_core', $join );
		$this->assertStringContainsString( '`wpdoflat_product_wp_core`.`_thumbnail_id` IS NOT NULL', $where );
	}

	public function test_no_group_by_is_added_for_one_row_per_post_joins(): void {
		unset( $GLOBALS['_wp_filter_callbacks']['posts_groupby'] );
		( new WPDO_Post_Query_Router() )->register_hooks();

		$this->assertEmpty( $GLOBALS['_wp_filter_callbacks']['posts_groupby'] ?? array() );
	}

	public function test_posts_where_appends_condition_for_routed_clause(): void {
		$this->set_post_mode( 'aeav_only' );

		$router = new WPDO_Post_Query_Router();
		$query  = $this->make_query( array(
			'post_type'  => 'product',
			'meta_query' => array(
				array( 'key' => '_price', 'value' => '99', 'compare' => '=', 'type' => 'NUMERIC' ),
			),
		) );

		$router->pre_get_posts( $query );
		$where = $router->posts_where( '', $query );

		$this->assertStringContainsString( '`_price`', $where );
		$this->assertStringContainsString( "'99'", $where );
	}

	public function test_pass_through_when_no_meta_query(): void {
		$this->set_post_mode( 'aeav_only' );

		$router = new WPDO_Post_Query_Router();
		$query  = $this->make_query( array( 'post_type' => 'product' ) );

		$router->pre_get_posts( $query );

		$this->assertSame( '', $query->get( 'wpdo_post_clauses' ) );
	}

	// ── all-or-nothing: native unless every registered clause is routable ────

	/**
	 * Run pre_get_posts in aeav_only and assert the query was left to WordPress.
	 *
	 * @param array<string, mixed> $vars Query vars.
	 */
	private function assert_not_routed( array $vars, string $why ): void {
		$this->set_post_mode( 'aeav_only' );
		$query = $this->make_query( $vars );
		( new WPDO_Post_Query_Router() )->pre_get_posts( $query );

		$this->assertSame( $vars['meta_query'], $query->get( 'meta_query' ), $why . ': meta_query untouched.' );
		$this->assertSame( '', $query->get( 'wpdo_post_clauses' ), $why . ': nothing routed.' );
	}

	public function test_or_relation_is_not_routed(): void {
		$this->assert_not_routed(
			array(
				'post_type'  => 'product',
				'meta_query' => array(
					'relation' => 'OR',
					array( 'key' => '_stock', 'value' => '1' ),
					array( 'key' => '_sku', 'value' => 'x' ),
				),
			),
			'OR'
		);
	}

	public function test_several_post_types_are_not_routed(): void {
		$this->assert_not_routed(
			array(
				'post_type'  => array( 'product', 'post' ),
				'meta_query' => array( array( 'key' => '_price', 'value' => '5', 'compare' => '>=', 'type' => 'NUMERIC' ) ),
			),
			'several post types'
		);
	}

	public function test_untyped_range_on_a_numeric_column_is_not_routed(): void {
		$this->assert_not_routed(
			array(
				'post_type'  => 'product',
				'meta_query' => array( array( 'key' => '_price', 'value' => '9000', 'compare' => '>' ) ),
			),
			'CHAR > on DECIMAL'
		);
	}

	public function test_untyped_equality_on_a_decimal_column_is_not_routed(): void {
		$this->assert_not_routed(
			array(
				'post_type'  => 'product',
				'meta_query' => array( array( 'key' => '_price', 'value' => '10' ) ),
			),
			'CHAR = on DECIMAL (native "10.00" != "10")'
		);
	}

	public function test_numeric_type_on_a_text_column_is_not_routed(): void {
		$this->assert_not_routed(
			array(
				'post_type'  => 'product',
				'meta_query' => array( array( 'key' => '_sku', 'value' => '5', 'compare' => '>', 'type' => 'NUMERIC' ) ),
			),
			'NUMERIC on VARCHAR'
		);
	}

	public function test_unknown_compare_is_not_routed(): void {
		$this->assert_not_routed(
			array(
				'post_type'  => 'product',
				'meta_query' => array( array( 'key' => '_sku', 'value' => '^a', 'compare' => 'REGEXP' ) ),
			),
			'REGEXP'
		);
	}

	public function test_one_unroutable_registered_clause_keeps_the_whole_query_native(): void {
		$this->assert_not_routed(
			array(
				'post_type'  => 'product',
				'meta_query' => array(
					array( 'key' => '_stock', 'value' => '3', 'compare' => '>=', 'type' => 'NUMERIC' ),
					array( 'key' => '_price', 'value' => '9000', 'compare' => '>' ),
				),
			),
			'one unroutable clause'
		);
	}

	public function test_nested_group_with_a_registered_key_is_not_routed(): void {
		$this->assert_not_routed(
			array(
				'post_type'  => 'product',
				'meta_query' => array(
					array( 'key' => '_stock', 'value' => '3', 'compare' => '>=', 'type' => 'NUMERIC' ),
					array(
						'relation' => 'OR',
						array( 'key' => '_price', 'compare' => 'NOT EXISTS' ),
						array( 'key' => '_price', 'compare' => 'EXISTS' ),
					),
				),
			),
			'nested group'
		);
	}

	public function test_untyped_integer_equality_on_an_integer_column_is_routed(): void {
		$this->set_post_mode( 'aeav_only' );
		$query = $this->make_query(
			array(
				'post_type'  => 'product',
				'meta_query' => array(
					array( 'key' => '_stock', 'value' => '3' ),
					array( 'key' => 'unmanaged_attr', 'value' => 'x' ),
				),
			)
		);
		( new WPDO_Post_Query_Router() )->pre_get_posts( $query );

		$this->assertNotEmpty( $query->get( 'wpdo_post_clauses' ) );
		$this->assertCount( 1, $query->get( 'meta_query' ), 'unregistered AND clause stays native' );
	}

	public function test_like_matches_an_escaped_substring(): void {
		$this->set_post_mode( 'aeav_only' );
		$router = new WPDO_Post_Query_Router();
		$query  = $this->make_query(
			array(
				'post_type'  => 'product',
				'meta_query' => array( array( 'key' => '_sku', 'value' => 'B1_1%', 'compare' => 'LIKE' ) ),
			)
		);
		$router->pre_get_posts( $query );

		$this->assertStringContainsString( "LIKE '%B1\\\\_1\\\\%%'", $router->posts_where( '', $query ) );
	}
}