<?php

namespace MediaWiki\Tests\Parser;

use BagOStuff;
use EmptyBagOStuff;
use HashBagOStuff;
use MediaWiki\HookContainer\HookContainer;
use MediaWikiIntegrationTestCase;
use MWTimestamp;
use NullStatsdDataFactory;
use ParserCache;
use ParserOptions;
use ParserOutput;
use Psr\Log\NullLogger;
use Title;
use WikiPage;

/**
 * @covers ParserCache
 * @group Database
 * @package MediaWiki\Tests\Parser
 */
class ParserCacheTest extends MediaWikiIntegrationTestCase {

	/** @var int */
	private $time;

	/** @var string */
	private $cacheTime;

	/** @var WikiPage */
	private $page;

	protected function setUp() : void {
		parent::setUp();

		$this->time = time();
		MWTimestamp::setFakeTime( $this->time );
		$this->page = $this->getExistingTestPage( __CLASS__ );
		$this->page->clear();
		$this->page->loadPageData();

		$this->cacheTime = MWTimestamp::convert( TS_MW, time() + 1 );

		// Clean up these tables after each test
		$this->tablesUsed = [
			'page',
			'revision',
			'comment',
			'text',
			'content'
		];
	}

	protected function tearDown() : void {
		MWTimestamp::setFakeTime( null );
		parent::tearDown();
	}

	/**
	 * @param HookContainer|null $hookContainer
	 * @param BagOStuff|null $storage
	 * @return ParserCache
	 */
	private function createParserCache(
		HookContainer $hookContainer = null,
		BagOStuff $storage = null
	): ParserCache {
		return new ParserCache(
			'test',
			$storage ?: new HashBagOStuff(),
			'19900220000000',
			$hookContainer ?: $this->createHookContainer( [] ),
			new NullStatsdDataFactory(),
			new NullLogger()
		);
	}

	/**
	 * @return array
	 */
	private function getDummyUsedOptions(): array {
		return array_slice(
			ParserOptions::allCacheVaryingOptions(),
			0,
			2
		);
	}

	/**
	 * @return ParserOutput
	 */
	private function createDummyParserOutput(): ParserOutput {
		$parserOutput = new ParserOutput();
		$parserOutput->setText( 'TEST' );
		foreach ( $this->getDummyUsedOptions() as $option ) {
			$parserOutput->recordOption( $option );
		}
		$parserOutput->updateCacheExpiry( 4242 );
		return $parserOutput;
	}

	/**
	 * Test that fetching without storing first returns false.
	 * @covers ParserCache::get
	 */
	public function testGetEmpty() {
		$cache = $this->createParserCache();
		$options = ParserOptions::newFromAnon();

		$this->assertFalse( $cache->get( $this->page, $options ) );
	}

	/**
	 * Test that fetching with the same options return the saved value.
	 * @covers ParserCache::get
	 * @covers ParserCache::save
	 */
	public function testSaveGetSameOptions() {
		$cache = $this->createParserCache();
		$parserOutput = new ParserOutput( 'TEST_TEXT' );

		$options1 = ParserOptions::newFromAnon();
		$options1->setOption( $this->getDummyUsedOptions()[0], 'value1' );
		$cache->save( $parserOutput, $this->page, $options1, $this->cacheTime );

		$savedOutput = $cache->get( $this->page, $options1 );
		$this->assertInstanceOf( ParserOutput::class, $savedOutput );
		// ParserCache adds a comment to the HTML, so check if the result starts with page content.
		$this->assertStringStartsWith( 'TEST_TEXT', $savedOutput->getText() );
		$this->assertSame( $this->cacheTime, $savedOutput->getCacheTime() );
		$this->assertSame( $this->page->getRevisionRecord()->getId(), $savedOutput->getCacheRevisionId() );
	}

	/**
	 * Test that fetching with different unused option returns a value.
	 * @covers ParserCache::get
	 * @covers ParserCache::save
	 */
	public function testSaveGetDifferentUnusedOption() {
		$cache = $this->createParserCache();
		$optionName = $this->getDummyUsedOptions()[0];
		$parserOutput = new ParserOutput( 'TEST_TEXT' );

		$options1 = ParserOptions::newFromAnon();
		$options1->setOption( $optionName, 'value1' );
		$cache->save( $parserOutput, $this->page, $options1, $this->cacheTime );

		$options2 = ParserOptions::newFromAnon();
		$options2->setOption( $optionName, 'value2' );
		$savedOutput = $cache->get( $this->page, $options2 );
		$this->assertInstanceOf( ParserOutput::class, $savedOutput );
		// ParserCache adds a comment to the HTML, so check if the result starts with page content.
		$this->assertStringStartsWith( 'TEST_TEXT', $savedOutput->getText() );
		$this->assertSame( $this->cacheTime, $savedOutput->getCacheTime() );
		$this->assertSame( $this->page->getRevisionRecord()->getId(), $savedOutput->getCacheRevisionId() );
	}

	/**
	 * Test that non-cacheable output is not stored
	 * @covers ParserCache::save
	 */
	public function testDoesNotStoreNonCacheable() {
		$cache = $this->createParserCache();
		$parserOutput = new ParserOutput( 'TEST_TEXT' );
		$parserOutput->updateCacheExpiry( 0 );

		$options1 = ParserOptions::newFromAnon();
		$cache->save( $parserOutput, $this->page, $options1, $this->cacheTime );

		$this->assertFalse( $cache->get( $this->page, $options1 ) );
		$this->assertFalse( $cache->get( $this->page, $options1, true ) );
		$this->assertFalse( $cache->getDirty( $this->page, $options1 ) );
	}

	/**
	 * Test that fetching with different used option don't return a value.
	 * @covers ParserCache::get
	 * @covers ParserCache::save
	 */
	public function testSaveGetDifferentUsedOption() {
		$cache = $this->createParserCache();
		$parserOutput = new ParserOutput( 'TEST_TEXT' );
		$optionName = $this->getDummyUsedOptions()[0];
		$parserOutput->recordOption( $optionName );

		$options1 = ParserOptions::newFromAnon();
		$options1->setOption( $optionName, 'value1' );
		$cache->save( $parserOutput, $this->page, $options1, $this->cacheTime );

		$options2 = ParserOptions::newFromAnon();
		$options2->setOption( $optionName, 'value2' );
		$this->assertFalse( $cache->get( $this->page, $options2 ) );
	}

	/**
	 * Test that output with expired metadata can be retrieved with getDirty
	 * @covers ParserCache::getDirty
	 * @covers ParserCache::get
	 */
	public function testGetExpiredMetadata() {
		$cache = $this->createParserCache();
		$parserOutput = new ParserOutput( 'TEST_TEXT' );
		$parserOutput->updateCacheExpiry( 10 );

		$options1 = ParserOptions::newFromAnon();
		$cache->save( $parserOutput, $this->page, $options1, $this->cacheTime );

		MWTimestamp::setFakeTime( $this->time + 15 * 1000 );
		$this->assertFalse( $cache->get( $this->page, $options1 ) );
		$this->assertInstanceOf( ParserOutput::class,
			$cache->get( $this->page, $options1, true ) );
		$this->assertInstanceOf( ParserOutput::class,
			$cache->getDirty( $this->page, $options1 ) );
	}

	/**
	 * Test that expired output with not expired metadata can be retrieved with getDirty
	 * @covers ParserCache::getDirty
	 * @covers ParserCache::get
	 */
	public function testGetExpiredContent() {
		$cache = $this->createParserCache();
		$optionName = $this->getDummyUsedOptions()[0];

		$parserOutput1 = new ParserOutput( 'TEST_TEXT1' );
		$parserOutput1->recordOption( $optionName );
		$parserOutput1->updateCacheExpiry( 10 );
		$options1 = ParserOptions::newFromAnon();
		$options1->setOption( $optionName, 'value1' );
		$cache->save( $parserOutput1, $this->page, $options1, $this->cacheTime );

		$parserOutput2 = new ParserOutput( 'TEST_TEXT2' );
		$parserOutput2->recordOption( $optionName );
		$parserOutput2->updateCacheExpiry( 100500600 );
		$options2 = ParserOptions::newFromAnon();
		$options2->setOption( $optionName, 'value2' );
		$cache->save( $parserOutput2, $this->page, $options2, $this->cacheTime );

		MWTimestamp::setFakeTime( $this->time + 15 * 1000 );
		$this->assertFalse( $cache->get( $this->page, $options1 ) );
		$this->assertInstanceOf( ParserOutput::class,
			$cache->get( $this->page, $options1, true ) );
		$this->assertInstanceOf( ParserOutput::class,
			$cache->getDirty( $this->page, $options1 ) );
	}

	/**
	 * Test that output with outdated metadata can be retrieved with getDirty
	 * @covers ParserCache::getDirty
	 * @covers ParserCache::get
	 */
	public function testGetOutdatedMetadata() {
		$cache = $this->createParserCache();
		$parserOutput = new ParserOutput( 'TEST_TEXT' );

		$options1 = ParserOptions::newFromAnon();
		$cache->save( $parserOutput, $this->page, $options1, $this->cacheTime );
		$this->assertInstanceOf( ParserOutput::class,
			$cache->get( $this->page, $options1 ) );

		$this->editPage( $this->page->getTitle()->getDBkey(), 'Test edit!' );
		$this->page->clear();

		$this->assertFalse( $cache->get( $this->page, $options1 ) );
		$this->assertInstanceOf( ParserOutput::class,
			$cache->get( $this->page, $options1, true ) );
		$this->assertInstanceOf( ParserOutput::class,
			$cache->getDirty( $this->page, $options1 ) );
	}

	/**
	 * Test that outdated output with good metadata can be retrieved with getDirty
	 * @covers ParserCache::getDirty
	 * @covers ParserCache::get
	 */
	public function testGetOutdatedContent() {
		$cache = $this->createParserCache();
		$optionName = $this->getDummyUsedOptions()[0];

		$parserOutput1 = new ParserOutput( 'TEST_TEXT' );
		$parserOutput1->recordOption( $optionName );
		$options1 = ParserOptions::newFromAnon();
		$options1->setOption( $optionName, 'value1' );
		$cache->save( $parserOutput1, $this->page, $options1, $this->cacheTime );

		$this->editPage( $this->page->getTitle()->getDBkey(), 'Test edit!' );
		$this->page->clear();

		$parserOutput2 = new ParserOutput( 'TEST_TEXT' );
		$parserOutput2->recordOption( $optionName );
		$options2 = ParserOptions::newFromAnon();
		$options2->setOption( $optionName, 'value2' );
		$cache->save( $parserOutput2, $this->page, $options2, $this->cacheTime );

		$this->assertFalse( $cache->get( $this->page, $options1 ) );
		$this->assertInstanceOf( ParserOutput::class,
			$cache->get( $this->page, $options1, true ) );
		$this->assertInstanceOf( ParserOutput::class,
			$cache->getDirty( $this->page, $options1 ) );
	}

	/**
	 * Test that fetching after deleting a key returns false.
	 * @covers ParserCache::deleteOptionsKey
	 */
	public function testDeleteOptionsKey() {
		$cache = $this->createParserCache();
		$parserOutput = new ParserOutput( 'TEST_TEXT' );

		$options1 = ParserOptions::newFromAnon();
		$cache->save( $parserOutput, $this->page, $options1, $this->cacheTime );
		$this->assertInstanceOf( ParserOutput::class,
			$cache->get( $this->page, $options1 ) );
		$cache->deleteOptionsKey( $this->page );

		$this->assertFalse( $cache->get( $this->page, $options1 ) );
	}

	/**
	 * Test that RejectParserCacheValue hook can reject ParserOutput
	 * @covers ParserCache::get
	 */
	public function testRejectedByHook() {
		$parserOutput = new ParserOutput( 'TEST_TEXT' );
		$options = ParserOptions::newFromAnon();
		$options->setOption( $this->getDummyUsedOptions()[0], 'value1' );
		$hookContainer = $this->createHookContainer( [
			'RejectParserCacheValue' =>
				function ( ParserOutput $value, WikiPage $hookPage, ParserOptions $popts )
				use ( $parserOutput, $options ) {
					$this->assertSame( $parserOutput, $value );
					$this->assertSame( $this->page, $hookPage );
					$this->assertSame( $options, $popts );
					return false;
				}
		] );
		$cache = $this->createParserCache( $hookContainer );
		$cache->save( $parserOutput, $this->page, $options, $this->cacheTime );
		$this->assertFalse( $cache->get( $this->page, $options ) );
	}

	/**
	 * Test that ParserCacheSaveComplete hook is run
	 * @covers ParserCache::save
	 */
	public function testParserCacheSaveCompleteHook() {
		$parserOutput = new ParserOutput( 'TEST_TEXT' );
		$options = ParserOptions::newFromAnon();
		$options->setOption( $this->getDummyUsedOptions()[0], 'value1' );
		$hookContainer = $this->createHookContainer( [
			'ParserCacheSaveComplete' =>
				function ( ParserCache $hookCache, ParserOutput $value,
						   Title $hookTitle, ParserOptions $popts, int $revId )
				use ( $parserOutput, $options ) {
					$this->assertSame( $parserOutput, $value );
					$this->assertSame( $this->page->getTitle(), $hookTitle );
					$this->assertSame( $options, $popts );
					$this->assertSame( 42, $revId );
				}
		] );
		$cache = $this->createParserCache( $hookContainer );
		$cache->save( $parserOutput, $this->page, $options, $this->cacheTime, 42 );
	}

	/**
	 * Tests that parser cache respects 'WikiPage::checkTouched'
	 * @covers ParserCache::get
	 */
	public function testRespectsCheckTouched() {
		$cache = $this->createParserCache();
		$mockPage = $this->createNoOpMock( WikiPage::class, [ 'checkTouched' ] );
		$mockPage->method( 'checkTouched' )
			->willReturn( false );
		$this->assertFalse( $cache->get( $mockPage, ParserOptions::newFromAnon() ) );
	}

	/**
	 * Tests that getCacheStorage returns underlying BagOStuff
	 * @covers ParserCache::getCacheStorage
	 */
	public function testGetCacheStorage() {
		$storage = new EmptyBagOStuff();
		$cache = $this->createParserCache( null, $storage );
		$this->assertSame( $storage, $cache->getCacheStorage() );
	}
}