<?php
declare(strict_types=1);

use PHPUnit\Framework\TestCase;

/**
 * Performance benchmark integration tests.
 *
 * Exercises Zone A (Hot), Zone B (Warm), and Zone C (Cold) with N=200
 * write + read operations and verifies data integrity. Timing is captured
 * and printed to STDOUT so it appears in --testdox output. No hard timing
 * assertions are made — correctness assertions guard against regressions.
 *
 * Run alone:  ./vendor/bin/phpunit --configuration phpunit-integration.xml
 *             --filter BenchmarkIntegrationTest --testdox
 */
class BenchmarkIntegrationTest extends TestCase {

	private const N         = 200;   // Rows per benchmark zone.
	private const POST_TYPE = 'bench';

	/** Zone A table: wp_itest_wpdo_hot_bench */
	private static string $hot_table;

	/** Zone B table: wp_itest_wpdo_warm_bench (isolated from other warm tests) */
	private static string $warm_table;

	/** Zone C table: wp_itest_wpdo_cold_bench */
	private static string $cold_table;

	/** Collected timing results printed in tearDownAfterClass(). */
	private static array $report = [];

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

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

		self::$hot_table  = $wpdb->prefix . 'wpdo_hot_bench';
		self::$warm_table = $wpdb->prefix . 'wpdo_warm_bench';
		self::$cold_table = $wpdb->prefix . 'wpdo_cold_bench';

		// Zone A table.
		$wpdb->query(
			"CREATE TABLE IF NOT EXISTS `" . self::$hot_table . "` (
				post_id    BIGINT(20) UNSIGNED NOT NULL DEFAULT 0,
				bench_val  DECIMAL(10,2)       DEFAULT NULL,
				updated_at DATETIME            NOT NULL DEFAULT '0000-00-00 00:00:00',
				PRIMARY KEY (post_id)
			) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4"
		);

		// Zone B table (KV schema).
		$wpdb->query(
			"CREATE TABLE IF NOT EXISTS `" . self::$warm_table . "` (
				id         BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
				post_id    BIGINT(20) UNSIGNED NOT NULL DEFAULT 0,
				meta_key   VARCHAR(255)        NOT NULL DEFAULT '',
				meta_value LONGTEXT            DEFAULT NULL,
				expires_at DATETIME            DEFAULT NULL,
				created_at DATETIME            NOT NULL DEFAULT CURRENT_TIMESTAMP,
				PRIMARY KEY (id),
				UNIQUE KEY post_meta (post_id, meta_key)
			) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4"
		);

		// Zone C table.
		$wpdb->query(
			"CREATE TABLE IF NOT EXISTS `" . self::$cold_table . "` (
				id         BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
				post_id    BIGINT(20) UNSIGNED NOT NULL DEFAULT 0,
				data       LONGTEXT            NOT NULL,
				updated_at DATETIME            NOT NULL DEFAULT '0000-00-00 00:00:00',
				PRIMARY KEY (id),
				UNIQUE KEY ui_post_id (post_id)
			) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4"
		);
	}

	public static function tearDownAfterClass(): void {
		global $wpdb;
		$wpdb->query( "DROP TABLE IF EXISTS `" . self::$hot_table  . "`" );
		$wpdb->query( "DROP TABLE IF EXISTS `" . self::$warm_table . "`" );
		$wpdb->query( "DROP TABLE IF EXISTS `" . self::$cold_table . "`" );

		// Print timing summary.
		fwrite( STDOUT, "\n\n  ── Benchmark Results (N=" . self::N . " per zone) ──────────────────────\n" );
		foreach ( self::$report as $label => $ms ) {
			fwrite( STDOUT, sprintf( "  %-40s %7.1f ms\n", $label, $ms ) );
		}
		fwrite( STDOUT, "  ──────────────────────────────────────────────────────\n\n" );
	}

	protected function setUp(): void {
		global $wpdb;
		$wpdb->query( "TRUNCATE TABLE `" . self::$hot_table  . "`" );
		$wpdb->query( "TRUNCATE TABLE `" . self::$warm_table . "`" );
		$wpdb->query( "TRUNCATE TABLE `" . self::$cold_table . "`" );
		$GLOBALS['_wp_cache'] = [];
	}

	// ── Zone A (Hot) ─────────────────────────────────────────────────────────

	public function test_zone_a_bulk_write_performance(): void {
		global $wpdb;
		$now   = gmdate( 'Y-m-d H:i:s' );
		$start = microtime( true );

		for ( $i = 1; $i <= self::N; $i++ ) {
			$wpdb->query(
				$wpdb->prepare(
					"INSERT INTO `" . self::$hot_table . "` (post_id, bench_val, updated_at)
					 VALUES (%d, %f, %s)
					 ON DUPLICATE KEY UPDATE bench_val = VALUES(bench_val), updated_at = VALUES(updated_at)",
					$i,
					$i * 10.0,
					$now
				)
			);
		}

		$ms = ( microtime( true ) - $start ) * 1000;
		self::$report['Zone A: ' . self::N . ' UPSERT writes'] = $ms;

		$count = (int) $wpdb->get_var( "SELECT COUNT(*) FROM `" . self::$hot_table . "`" );
		$this->assertSame( self::N, $count, 'Zone A: all rows written' );
	}

	public function test_zone_a_bulk_read_performance(): void {
		global $wpdb;

		// Seed data.
		$now = gmdate( 'Y-m-d H:i:s' );
		for ( $i = 1; $i <= self::N; $i++ ) {
			$wpdb->query( $wpdb->prepare(
				"INSERT INTO `" . self::$hot_table . "` (post_id, bench_val, updated_at) VALUES (%d, %f, %s)",
				$i, $i * 10.0, $now
			) );
		}

		// Benchmark individual point-reads.
		$start  = microtime( true );
		$values = [];
		for ( $i = 1; $i <= self::N; $i++ ) {
			$values[] = $wpdb->get_var(
				$wpdb->prepare( "SELECT bench_val FROM `" . self::$hot_table . "` WHERE post_id = %d", $i )
			);
		}
		$ms = ( microtime( true ) - $start ) * 1000;
		self::$report['Zone A: ' . self::N . ' point reads']   = $ms;

		$this->assertCount( self::N, $values, 'Zone A: all rows readable' );
		$this->assertSame( '10.00', $values[0] ); // post_id=1 → 1*10=10
	}

	public function test_zone_a_filtered_query_performance(): void {
		global $wpdb;

		$now = gmdate( 'Y-m-d H:i:s' );
		for ( $i = 1; $i <= self::N; $i++ ) {
			$wpdb->query( $wpdb->prepare(
				"INSERT INTO `" . self::$hot_table . "` (post_id, bench_val, updated_at) VALUES (%d, %f, %s)",
				$i, $i * 10.0, $now
			) );
		}

		// Filtered query: bench_val >= 1000 (100 rows).
		$start = microtime( true );
		$rows  = $wpdb->get_results(
			$wpdb->prepare(
				"SELECT post_id, bench_val FROM `" . self::$hot_table . "` WHERE bench_val >= %f ORDER BY bench_val ASC",
				1000.0
			),
			ARRAY_A
		);
		$ms = ( microtime( true ) - $start ) * 1000;
		self::$report['Zone A: filtered query (half dataset)'] = $ms;

		$this->assertCount( 101, $rows, 'Zone A: filter returns correct row count' );
		$this->assertSame( '1000.00', $rows[0]['bench_val'] );
	}

	// ── Zone B (Warm) ─────────────────────────────────────────────────────────

	public function test_zone_b_bulk_write_performance(): void {
		global $wpdb;
		$now   = gmdate( 'Y-m-d H:i:s' );
		$start = microtime( true );

		for ( $i = 1; $i <= self::N; $i++ ) {
			$wpdb->query(
				$wpdb->prepare(
					"INSERT INTO `" . self::$warm_table . "`
					 (post_id, meta_key, meta_value, created_at)
					 VALUES (%d, %s, %s, %s)
					 ON DUPLICATE KEY UPDATE meta_value = VALUES(meta_value)",
					$i, 'bench_views', (string) $i, $now
				)
			);
		}

		$ms = ( microtime( true ) - $start ) * 1000;
		self::$report['Zone B: ' . self::N . ' KV writes']     = $ms;

		$count = (int) $wpdb->get_var( "SELECT COUNT(*) FROM `" . self::$warm_table . "`" );
		$this->assertSame( self::N, $count, 'Zone B: all KV rows written' );
	}

	public function test_zone_b_bulk_read_performance(): void {
		global $wpdb;

		$now = gmdate( 'Y-m-d H:i:s' );
		for ( $i = 1; $i <= self::N; $i++ ) {
			$wpdb->query( $wpdb->prepare(
				"INSERT INTO `" . self::$warm_table . "` (post_id, meta_key, meta_value, created_at) VALUES (%d, %s, %s, %s)",
				$i, 'bench_views', (string) $i, $now
			) );
		}

		$start  = microtime( true );
		$values = [];
		for ( $i = 1; $i <= self::N; $i++ ) {
			$values[] = $wpdb->get_var( $wpdb->prepare(
				"SELECT meta_value FROM `" . self::$warm_table . "` WHERE post_id = %d AND meta_key = %s",
				$i, 'bench_views'
			) );
		}
		$ms = ( microtime( true ) - $start ) * 1000;
		self::$report['Zone B: ' . self::N . ' KV reads']      = $ms;

		$this->assertCount( self::N, $values, 'Zone B: all KV rows readable' );
		$this->assertSame( '1', $values[0] ); // post_id=1 → value=1
	}

	// ── Zone C (Cold) ─────────────────────────────────────────────────────────

	public function test_zone_c_bulk_write_performance(): void {
		global $wpdb;
		$now   = gmdate( 'Y-m-d H:i:s' );
		$start = microtime( true );

		for ( $i = 1; $i <= self::N; $i++ ) {
			$json = wp_json_encode( [
				'hp_description' => 'Benchmark listing description number ' . $i,
				'hp_website'     => 'https://listing' . $i . '.example.com',
				'hp_facebook'    => 'https://facebook.com/listing' . $i,
			] );
			$wpdb->query(
				$wpdb->prepare(
					"INSERT INTO `" . self::$cold_table . "` (post_id, data, updated_at)
					 VALUES (%d, %s, %s)
					 ON DUPLICATE KEY UPDATE data = VALUES(data), updated_at = VALUES(updated_at)",
					$i, $json, $now
				)
			);
		}

		$ms = ( microtime( true ) - $start ) * 1000;
		self::$report['Zone C: ' . self::N . ' JSON blob writes'] = $ms;

		$count = (int) $wpdb->get_var( "SELECT COUNT(*) FROM `" . self::$cold_table . "`" );
		$this->assertSame( self::N, $count, 'Zone C: all JSON rows written' );
	}

	public function test_zone_c_bulk_read_performance(): void {
		global $wpdb;

		$now = gmdate( 'Y-m-d H:i:s' );
		for ( $i = 1; $i <= self::N; $i++ ) {
			$json = wp_json_encode( [
				'hp_description' => 'Description ' . $i,
				'hp_website'     => 'https://listing' . $i . '.example.com',
			] );
			$wpdb->query( $wpdb->prepare(
				"INSERT INTO `" . self::$cold_table . "` (post_id, data, updated_at) VALUES (%d, %s, %s)",
				$i, $json, $now
			) );
		}

		$start   = microtime( true );
		$decoded = 0;
		for ( $i = 1; $i <= self::N; $i++ ) {
			$json = $wpdb->get_var( $wpdb->prepare(
				"SELECT data FROM `" . self::$cold_table . "` WHERE post_id = %d",
				$i
			) );
			$data = json_decode( (string) $json, true );
			if ( is_array( $data ) && isset( $data['hp_description'] ) ) {
				$decoded++;
			}
		}
		$ms = ( microtime( true ) - $start ) * 1000;
		self::$report['Zone C: ' . self::N . ' JSON blob reads'] = $ms;

		$this->assertSame( self::N, $decoded, 'Zone C: all JSON blobs readable' );
	}
}