<?php

namespace SilverStripe\VersionFeed\Tests;

use Page;
use PageController;
use Psr\SimpleCache\CacheInterface;
use SilverStripe\CMS\Model\SiteTree;
use SilverStripe\Control\Director;
use SilverStripe\Core\Cache\CacheFactory;
use SilverStripe\Core\Config\Config;
use SilverStripe\Core\Injector\Injector;
use SilverStripe\Dev\FunctionalTest;
use SilverStripe\SiteConfig\SiteConfig;
use SilverStripe\Versioned\Versioned;
use SilverStripe\VersionFeed\Filters\CachedContentFilter;
use SilverStripe\VersionFeed\Filters\RateLimitFilter;
use SilverStripe\VersionFeed\VersionFeed;
use SilverStripe\VersionFeed\VersionFeedController;

class VersionFeedFunctionalTest extends FunctionalTest
{
    protected $usesDatabase = true;

    protected $baseURI = 'http://www.fakesite.test';

    protected static $required_extensions = [
        Page::class => [VersionFeed::class],
        PageController::class => [VersionFeedController::class],
    ];

    protected $userIP;

    /**
     * @var CacheInterface
     */
    protected $cache;

    protected function setUp(): void
    {
        Director::config()->set('alternate_base_url', $this->baseURI);

        parent::setUp();

        $this->cache = Injector::inst()->get(
            CacheInterface::class . '.VersionFeedController'
        );
        $this->cache->clear();

        $this->userIP = isset($_SERVER['REMOTE_ADDR']) ? $_SERVER['REMOTE_ADDR'] : null;

        // Enable history by default
        Config::modify()->set(VersionFeed::class, 'changes_enabled', true);
        Config::modify()->set(VersionFeed::class, 'allchanges_enabled', true);

        // Disable caching and locking by default
        Config::modify()->set(CachedContentFilter::class, 'cache_enabled', false);
        Config::modify()->set(RateLimitFilter::class, 'lock_timeout', 0);
        Config::modify()->set(RateLimitFilter::class, 'lock_bypage', false);
        Config::modify()->set(RateLimitFilter::class, 'lock_byuserip', false);
        Config::modify()->set(RateLimitFilter::class, 'lock_cooldown', false);

        // Ensure any version based caches read from the live cache
        Versioned::set_reading_mode(Versioned::DEFAULT_MODE);
    }

    protected function tearDown(): void
    {
        Director::config()->set('alternate_base_url', null);

        $_SERVER['REMOTE_ADDR'] = $this->userIP;

        parent::tearDown();
    }

    public function testPublicHistoryPublicHistoryDisabled()
    {
        $page = $this->createPageWithChanges(['PublicHistory' => false]);

        $response = $this->get($page->RelativeLink('changes'));
        $this->assertEquals(
            404,
            $response->getStatusCode(),
            'With Page\'s "PublicHistory" disabled, `changes` action response code should be 404'
        );

        $response = $this->get($page->RelativeLink('allchanges'));
        $this->assertEquals(200, $response->getStatusCode());
        $xml = simplexml_load_string($response->getBody() ?? '');
        $this->assertFalse(
            (bool)$xml->channel->item,
            'With Page\'s "PublicHistory" disabled, `allchanges` action should not have an item in the channel'
        );
    }

    public function testPublicHistoryPublicHistoryEnabled()
    {
        $page = $this->createPageWithChanges(['PublicHistory' => true]);

        $response = $this->get($page->RelativeLink('changes'));
        $this->assertEquals(200, $response->getStatusCode());
        $xml = simplexml_load_string($response->getBody() ?? '');
        $this->assertTrue(
            (bool)$xml->channel->item,
            'With Page\'s "PublicHistory" enabled, `changes` action should have an item in the channel'
        );

        $response = $this->get($page->RelativeLink('allchanges'));
        $this->assertEquals(200, $response->getStatusCode());
        $xml = simplexml_load_string($response->getBody() ?? '');
        $this->assertTrue(
            (bool)$xml->channel->item,
            'With "PublicHistory" enabled, `allchanges` action should have an item in the channel'
        );
    }

    public function testRateLimiting()
    {
        // Re-enable locking just for this test
        Config::modify()->set(RateLimitFilter::class, 'lock_timeout', 20);
        Config::modify()->set(CachedContentFilter::class, 'cache_enabled', true);

        $page1 = $this->createPageWithChanges(['PublicHistory' => true, 'Title' => 'Page1']);
        $page2 = $this->createPageWithChanges(['PublicHistory' => true, 'Title' => 'Page2']);

        // Artifically set cache lock
        $this->cache->set(RateLimitFilter::CACHE_PREFIX, time() + 10);

        // Test normal hit
        $response = $this->get($page1->RelativeLink('changes'));
        $this->assertEquals(429, $response->getStatusCode());
        $this->assertGreaterThan(0, $response->getHeader('Retry-After'));
        $response = $this->get($page2->RelativeLink('changes'));
        $this->assertEquals(429, $response->getStatusCode());
        $this->assertGreaterThan(0, $response->getHeader('Retry-After'));

        // Test page specific lock
        Config::modify()->set(RateLimitFilter::class, 'lock_bypage', true);
        $key = implode('_', [
            'changes',
            $page1->ID,
            Versioned::get_versionnumber_by_stage(SiteTree::class, 'Live', $page1->ID, false)
        ]);
        $key = RateLimitFilter::CACHE_PREFIX . '_' . md5($key ?? '');
        $this->cache->set($key, time() + 10);
        $response = $this->get($page1->RelativeLink('changes'));
        $this->assertEquals(429, $response->getStatusCode());
        $this->assertGreaterThan(0, $response->getHeader('Retry-After'));
        $response = $this->get($page2->RelativeLink('changes'));
        $this->assertEquals(200, $response->getStatusCode());
        Config::modify()->set(RateLimitFilter::class, 'lock_bypage', false);

        // Test rate limit hit by IP
        Config::modify()->set(RateLimitFilter::class, 'lock_byuserip', true);
        $_SERVER['REMOTE_ADDR'] = '127.0.0.1';
        $this->cache->set(RateLimitFilter::CACHE_PREFIX . '_' . md5('127.0.0.1'), time() + 10);
        $response = $this->get($page1->RelativeLink('changes'));
        $this->assertEquals(429, $response->getStatusCode());
        $this->assertGreaterThan(0, $response->getHeader('Retry-After'));

        // Test rate limit doesn't hit other IP
        $_SERVER['REMOTE_ADDR'] = '127.0.0.20';
        $this->cache->set(RateLimitFilter::CACHE_PREFIX . '_' . md5('127.0.0.1'), time() + 10);
        $response = $this->get($page1->RelativeLink('changes'));
        $this->assertEquals(200, $response->getStatusCode());
    }

    public function testChangesActionContainsChangesForCurrentPageOnly()
    {
        $page1 = $this->createPageWithChanges(['Title' => 'Page1']);
        $page2 = $this->createPageWithChanges(['Title' => 'Page2']);

        $response = $this->get($page1->RelativeLink('changes'));
        $xml = simplexml_load_string($response->getBody() ?? '');
        $titles = array_map(function ($item) {
            return (string)$item->title;
        }, $xml->xpath('//item') ?? []);

        $this->assertContains('Changed: Page1', $titles);
        $this->assertNotContains('Changed: Page2', $titles);

        $response = $this->get($page2->RelativeLink('changes'));
        $xml = simplexml_load_string($response->getBody() ?? '');
        $titles = array_map(function ($item) {
            return (string)$item->title;
        }, $xml->xpath('//item') ?? []);

        $this->assertNotContains('Changed: Page1', $titles);
        $this->assertContains('Changed: Page2', $titles);
    }

    public function testAllChangesActionContainsAllChangesForAllPages()
    {
        $page1 = $this->createPageWithChanges(['Title' => 'Page1']);
        $page2 = $this->createPageWithChanges(['Title' => 'Page2']);

        $response = $this->get($page1->RelativeLink('allchanges'));
        $xml = simplexml_load_string($response->getBody() ?? '');
        $titles = array_map(function ($item) {
            return str_replace('Changed: ', '', (string) $item->title);
        }, $xml->xpath('//item') ?? []);
        $this->assertContains('Page1', $titles);
        $this->assertContains('Page2', $titles);
    }

    protected function createPageWithChanges($seed = null)
    {
        $page = new Page();

        $seed = array_merge([
            'Title' => 'My Title',
            'Content' => 'My Content'
        ], $seed);
        $page->update($seed);
        $page->write();
        $page->publishSingle();

        $page->update([
            'Title' => 'Changed: ' . $seed['Title'],
            'Content' => 'Changed: ' . $seed['Content'],
        ]);
        $page->write();
        $page->publishSingle();

        $page->update([
            'Title' => 'Changed again: ' . $seed['Title'],
            'Content' => 'Changed again: ' . $seed['Content'],
        ]);
        $page->write();
        $page->publishSingle();

        $page->update([
            'Title' => 'Unpublished: ' . $seed['Title'],
            'Content' => 'Unpublished: ' . $seed['Content'],
        ]);
        $page->write();

        return $page;
    }

    /**
     * Tests response code for globally disabled feeds
     */
    public function testFeedViewability()
    {

        // Nested loop through each configuration
        foreach ([true, false] as $publicHistory_Page) {
            $page = $this->createPageWithChanges(['PublicHistory' => $publicHistory_Page, 'Title' => 'Page']);

            // Test requests to 'changes' action
            foreach ([true, false] as $publicHistory_Config) {
                Config::modify()->set(VersionFeed::class, 'changes_enabled', $publicHistory_Config);
                $expectedResponse = $publicHistory_Page && $publicHistory_Config ? 200 : 404;
                $response = $this->get($page->RelativeLink('changes'));
                $this->assertEquals($expectedResponse, $response->getStatusCode());
            }

            // Test requests to 'allchanges' action on each page
            foreach ([true, false] as $allChanges_Config) {
                foreach ([true, false] as $allChanges_SiteConfig) {
                    Config::modify()->set(VersionFeed::class, 'allchanges_enabled', $allChanges_Config);
                    $siteConfig = SiteConfig::current_site_config();
                    $siteConfig->AllChangesEnabled = $allChanges_SiteConfig;
                    $siteConfig->write();

                    $expectedResponse = $allChanges_Config && $allChanges_SiteConfig ? 200 : 404;
                    $response = $this->get($page->RelativeLink('allchanges'));
                    $this->assertEquals($expectedResponse, $response->getStatusCode());
                }
            }
        }
    }
}