<?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();
	}

	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' => '>=' ),
			),
		) );
		$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' => '>=' ),
			),
		) );
		$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' => '>=' ),
			),
		) );

		$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' => '>=' ),
				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' => '>=' ),
			),
		) );
		$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' ),
			),
			'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_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' => '=' ),
			),
		) );

		$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' ) );
	}
}