<?php

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
namespace CloudObjects\SDK;

use ML\IRI\IRI;
use GuzzleHttp\Client, GuzzleHttp\Handler\MockHandler,
    GuzzleHttp\HandlerStack, GuzzleHttp\Psr7\Request, GuzzleHttp\Psr7\Response;
use GuzzleHttp\Exception\ConnectException, GuzzleHttp\Exception\RequestException;
use CloudObjects\SDK\Exceptions\CoreAPIException;

class ObjectRetrieverMockTest extends \PHPUnit\Framework\TestCase {

    private $retriever;

    /**
     * @param Response|\Throwable ...$responses Responses in the order they are returned,
     *  or exceptions to throw instead.
     */
    private function setMockResponse(...$responses) : MockHandler {
        $mock = new MockHandler($responses);
        $handler = HandlerStack::create($mock);
        $this->retriever->setClient(new Client(['handler' => $handler]));
        return $mock;
    }

    protected function setUp(): void {
        $this->retriever = new ObjectRetriever;
    }

    public function testGetRootResource() {
        $this->setMockResponse(new Response(200,
            ['Content-Type' => 'application/ld+json'],
            '{"@context":{"cloudobjects":"coid:\/\/cloudobjects.io\/","rdf":"http:\/\/www.w3.org\/1999\/02\/22-rdf-syntax-ns#","rdfs":"http:\/\/www.w3.org\/2000\/01\/rdf-schema#"},"@id":"coid:\/\/cloudobjects.io","@type":"cloudobjects:Namespace","cloudobjects:hasPublicListing":"true","cloudobjects:revision":"1-325baa62b76105f56dc09386f5a2ec91","rdfs:comment":"The CloudObjects namespace defines the essential objects.","rdfs:label":"CloudObjects"}'
        ));

        $coid = new IRI('coid://cloudobjects.io');

        // Test node interface first
        $object = $this->retriever->getObjectNode($coid);
        $this->assertNotNull($object);
        $this->assertEquals((string)$coid, $object->getId());
        $this->assertNotNull($object->getProperty('http://www.w3.org/2000/01/rdf-schema#label'));
        $this->assertEquals('CloudObjects', $object->getProperty('http://www.w3.org/2000/01/rdf-schema#label')->getValue());
        $this->assertNull($object->getProperty('urn:example:nonexistingvalue'));

        // Test CloudObject interface
        $object = $this->retriever->getCloudObject($coid);
        $this->assertNotNull($object);
        $this->assertEquals((string)$coid, $object->getAsNode()->getId());
        $this->assertEquals($coid, $object->getCOID());
        $this->assertNotNull($object->getString('http://www.w3.org/2000/01/rdf-schema#label'));
        $this->assertEquals('CloudObjects', $object->getString('http://www.w3.org/2000/01/rdf-schema#label'));
        $this->assertNull($object->getString('urn:example:nonexistingvalue'));
    }

    public function testGetNonExistingResource() {
        $this->setMockResponse(new Response(404));

        // should return "null"        
        $coid = new IRI('coid://nonexistingresource.example.com');

        $object = $this->retriever->getObjectNode($coid);
        $this->assertNull($object);
    }

    public function testWhenAPIThrowsError() {
        $this->setMockResponse(new Response(500));

        $coid = new IRI('coid://nonexistingresource.example.com');

        $this->expectException(CoreAPIException::class);
        $this->retriever->getObjectNode($coid);
    }

    public function testWhenAPITimesOut() {
        $this->setMockResponse(new ConnectException(
            'cURL error 28: Operation timed out',
            new Request('GET', 'cloudobjects.io')
        ));

        $coid = new IRI('coid://cloudobjects.io');

        try {
            $this->retriever->getObjectNode($coid);
            $this->fail('Expected CoreAPIException was not thrown.');
        } catch (CoreAPIException $e) {
            $this->assertInstanceOf(ConnectException::class, $e->getPrevious());
        }
    }

    public function testGetAttachment() {
        $mock = $this->setMockResponse(
            new Response(200, ['Content-Type' => 'application/ld+json'],
                '{"@id":"coid://cloudobjects.io/Test","coid://cloudobjects.io/isAtRevision":"1-abc"}'),
            new Response(200, ['Content-Type' => 'text/plain'], 'Attachment content')
        );

        $content = $this->retriever->getAttachment(new IRI('coid://cloudobjects.io/Test'), 'file.txt');
        $this->assertEquals('Attachment content', $content);
        $this->assertStringEndsWith('cloudobjects.io/Test/file.txt', $mock->getLastRequest()->getUri()->getPath());
    }

    public function testGetMissingAttachment() {
        $this->setMockResponse(
            new Response(200, ['Content-Type' => 'application/ld+json'],
                '{"@id":"coid://cloudobjects.io/Test","coid://cloudobjects.io/isAtRevision":"1-abc"}'),
            new Response(404)
        );

        $content = $this->retriever->getAttachment(new IRI('coid://cloudobjects.io/Test'), 'missing.txt');
        $this->assertNull($content);
    }

    private function createFallbackStoreDirectory() : string {
        $directory = sys_get_temp_dir().DIRECTORY_SEPARATOR.'clobj-fallback-'.uniqid();
        mkdir($directory);
        return $directory;
    }

    private function removeDirectory(string $directory) {
        $files = new \RecursiveIteratorIterator(
            new \RecursiveDirectoryIterator($directory, \FilesystemIterator::SKIP_DOTS),
            \RecursiveIteratorIterator::CHILD_FIRST
        );
        foreach ($files as $file)
            $file->isDir() ? rmdir($file->getPathname()) : unlink($file->getPathname());
        rmdir($directory);
    }

    public function testFallbackStoreSavesObjectInScope() {
        $directory = $this->createFallbackStoreDirectory();
        $this->retriever = new ObjectRetriever([
            'fallback_store_directory' => $directory,
            'fallback_store_scope' => 'example.com, cloudobjects.io',
        ]);
        $body = '{"@id":"coid://cloudobjects.io/Test","http://www.w3.org/2000/01/rdf-schema#label":"Test"}';
        $this->setMockResponse(new Response(200, ['Content-Type' => 'application/ld+json'], $body));

        try {
            $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));

            $location = $directory.'/cloudobjects.io/Test/object.jsonld';
            $this->assertFileExists($location);
            $this->assertEquals($body, file_get_contents($location));
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testFallbackStoreSkipsObjectOutOfScope() {
        $directory = $this->createFallbackStoreDirectory();
        $this->retriever = new ObjectRetriever([
            'fallback_store_directory' => $directory,
            'fallback_store_scope' => [ 'example.com' ],
        ]);
        $this->setMockResponse(new Response(200, ['Content-Type' => 'application/ld+json'],
            '{"@id":"coid://cloudobjects.io/Test"}'));

        try {
            $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
            $this->assertFileDoesNotExist($directory.'/cloudobjects.io/Test/object.jsonld');
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testFallbackStoreSavesAllObjectsWithWildcard() {
        $directory = $this->createFallbackStoreDirectory();
        $this->retriever = new ObjectRetriever([
            'fallback_store_directory' => $directory,
            'fallback_store_scope' => '*',
        ]);
        $this->setMockResponse(new Response(200, ['Content-Type' => 'application/ld+json'],
            '{"@id":"coid://cloudobjects.io"}'));

        try {
            $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io'));
            $this->assertFileExists($directory.'/cloudobjects.io/object.jsonld');
        } finally {
            $this->removeDirectory($directory);
        }
    }

    private function createRetrieverWithStoredObject(string $directory) {
        $this->retriever = new ObjectRetriever([
            'fallback_store_directory' => $directory,
            'fallback_store_scope' => '*',
        ]);
        mkdir($directory.'/cloudobjects.io/Test', 0777, true);
        file_put_contents($directory.'/cloudobjects.io/Test/object.jsonld',
            '{"@id":"coid://cloudobjects.io/Test","http://www.w3.org/2000/01/rdf-schema#label":"Stored"}');
    }

    public function testFallbackStoreUsedWhenAPIReturns500() {
        $directory = $this->createFallbackStoreDirectory();
        $this->createRetrieverWithStoredObject($directory);
        $this->setMockResponse(new Response(500));

        try {
            $object = $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
            $this->assertNotNull($object);
            $this->assertEquals('Stored', $object->getProperty('http://www.w3.org/2000/01/rdf-schema#label')->getValue());
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testFallbackStoreUsedWhenAPITimesOut() {
        $directory = $this->createFallbackStoreDirectory();
        $this->createRetrieverWithStoredObject($directory);
        $this->setMockResponse(new ConnectException(
            'cURL error 28: Operation timed out',
            new Request('GET', 'cloudobjects.io')
        ));

        try {
            $object = $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
            $this->assertNotNull($object);
            $this->assertEquals('Stored', $object->getProperty('http://www.w3.org/2000/01/rdf-schema#label')->getValue());
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testFallbackStoreUsedWhenRequestFailsWithoutResponse() {
        $directory = $this->createFallbackStoreDirectory();
        $this->createRetrieverWithStoredObject($directory);
        $this->setMockResponse(new RequestException(
            'Request failed',
            new Request('GET', 'cloudobjects.io')
        ));

        try {
            $object = $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
            $this->assertNotNull($object);
            $this->assertEquals('Stored', $object->getProperty('http://www.w3.org/2000/01/rdf-schema#label')->getValue());
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testErrorWhenRequestFailsWithoutResponseAndObjectNotInFallbackStore() {
        $directory = $this->createFallbackStoreDirectory();
        $this->retriever = new ObjectRetriever([
            'fallback_store_directory' => $directory,
            'fallback_store_scope' => '*',
        ]);
        $this->setMockResponse(new RequestException(
            'Request failed',
            new Request('GET', 'cloudobjects.io')
        ));

        try {
            $this->expectException(CoreAPIException::class);
            $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testFallbackStoreNotUsedOnClientError() {
        $directory = $this->createFallbackStoreDirectory();
        $this->createRetrieverWithStoredObject($directory);
        $this->setMockResponse(new Response(403));

        try {
            $this->expectException(CoreAPIException::class);
            $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testErrorWhenAPIThrowsErrorAndObjectNotInFallbackStore() {
        $directory = $this->createFallbackStoreDirectory();
        $this->retriever = new ObjectRetriever([
            'fallback_store_directory' => $directory,
            'fallback_store_scope' => '*',
        ]);
        $this->setMockResponse(new Response(500));

        try {
            $this->expectException(CoreAPIException::class);
            $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
        } finally {
            $this->removeDirectory($directory);
        }
    }

    private function createRetrieverWithPermanentObject(string $directory, array $options = []) {
        $this->retriever = new ObjectRetriever(array_merge([
            'permanent_store_directory' => $directory,
            'permanent_store_scope' => '*',
        ], $options));
        mkdir($directory.'/cloudobjects.io/Test', 0777, true);
        file_put_contents($directory.'/cloudobjects.io/Test/object.jsonld',
            '{"@id":"coid://cloudobjects.io/Test","http://www.w3.org/2000/01/rdf-schema#label":"Stored"}');
    }

    public function testPermanentStoreSavesObjectInScope() {
        $directory = $this->createFallbackStoreDirectory();
        $this->retriever = new ObjectRetriever([
            'permanent_store_directory' => $directory,
            'permanent_store_scope' => 'example.com, cloudobjects.io',
        ]);
        $body = '{"@id":"coid://cloudobjects.io/Test","http://www.w3.org/2000/01/rdf-schema#label":"Test"}';
        $this->setMockResponse(new Response(200, ['Content-Type' => 'application/ld+json'], $body));

        try {
            $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));

            $location = $directory.'/cloudobjects.io/Test/object.jsonld';
            $this->assertFileExists($location);
            $this->assertEquals($body, file_get_contents($location));
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testPermanentStoreSkipsObjectOutOfScope() {
        $directory = $this->createFallbackStoreDirectory();
        $this->retriever = new ObjectRetriever([
            'permanent_store_directory' => $directory,
            'permanent_store_scope' => [ 'example.com' ],
        ]);
        $this->setMockResponse(new Response(200, ['Content-Type' => 'application/ld+json'],
            '{"@id":"coid://cloudobjects.io/Test"}'));

        try {
            $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
            $this->assertFileDoesNotExist($directory.'/cloudobjects.io/Test/object.jsonld');
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testPermanentStoreUsedWithoutContactingAPI() {
        $directory = $this->createFallbackStoreDirectory();
        $this->createRetrieverWithPermanentObject($directory);
        $mock = new MockHandler([ new Response(500) ]);
        $this->retriever->setClient(new Client(['handler' => HandlerStack::create($mock)]));

        try {
            $object = $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
            $this->assertNotNull($object);
            $this->assertEquals('Stored', $object->getProperty('http://www.w3.org/2000/01/rdf-schema#label')->getValue());
            // The mocked response has not been consumed
            $this->assertCount(1, $mock);
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testPermanentStoreNotOverwritten() {
        $directory = $this->createFallbackStoreDirectory();
        $this->createRetrieverWithPermanentObject($directory);
        $this->setMockResponse(new Response(200, ['Content-Type' => 'application/ld+json'],
            '[{"@id":"coid://cloudobjects.io/Test","http://www.w3.org/2000/01/rdf-schema#label":"Updated"}]'));

        try {
            $this->retriever->fetchAllObjectsInNamespace(new IRI('coid://cloudobjects.io'));
            $this->assertStringContainsString('Stored',
                file_get_contents($directory.'/cloudobjects.io/Test/object.jsonld'));
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testPermanentStoreTakesPrecedenceOverFallbackStore() {
        $permanentDirectory = $this->createFallbackStoreDirectory();
        $fallbackDirectory = $this->createFallbackStoreDirectory();
        $this->createRetrieverWithPermanentObject($permanentDirectory, [
            'fallback_store_directory' => $fallbackDirectory,
            'fallback_store_scope' => '*',
        ]);
        mkdir($fallbackDirectory.'/cloudobjects.io/Test', 0777, true);
        file_put_contents($fallbackDirectory.'/cloudobjects.io/Test/object.jsonld',
            '{"@id":"coid://cloudobjects.io/Test","http://www.w3.org/2000/01/rdf-schema#label":"Fallback"}');
        $this->setMockResponse(new Response(500));

        try {
            $object = $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
            $this->assertEquals('Stored', $object->getProperty('http://www.w3.org/2000/01/rdf-schema#label')->getValue());
        } finally {
            $this->removeDirectory($permanentDirectory);
            $this->removeDirectory($fallbackDirectory);
        }
    }

    private function createStaticObjectDirectory() : string {
        $directory = $this->createFallbackStoreDirectory();
        mkdir($directory.'/cloudobjects.io/Test', 0777, true);
        file_put_contents($directory.'/cloudobjects.io/Test/object.jsonld',
            '{"@id":"coid://cloudobjects.io/Test","http://www.w3.org/2000/01/rdf-schema#label":"Static"}');
        return $directory;
    }

    public function testStaticObjectDirectoryUsedWithoutContactingAPI() {
        $directory = $this->createStaticObjectDirectory();
        $this->retriever = new ObjectRetriever([
            'static_object_directory' => $directory,
        ]);
        $mock = new MockHandler([ new Response(500) ]);
        $this->retriever->setClient(new Client(['handler' => HandlerStack::create($mock)]));

        try {
            $object = $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
            $this->assertEquals('Static', $object->getProperty('http://www.w3.org/2000/01/rdf-schema#label')->getValue());
            // The mocked response has not been consumed
            $this->assertCount(1, $mock);
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testStaticObjectDirectoryWithDeprecatedOptionName() {
        $directory = $this->createStaticObjectDirectory();
        $this->retriever = new ObjectRetriever([
            'static_config_path' => $directory,
        ]);
        $this->setMockResponse(new Response(500));

        try {
            $object = $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Test'));
            $this->assertEquals('Static', $object->getProperty('http://www.w3.org/2000/01/rdf-schema#label')->getValue());
        } finally {
            $this->removeDirectory($directory);
        }
    }

    public function testStaticObjectDirectoryFallsThroughToAPI() {
        $directory = $this->createStaticObjectDirectory();
        $this->retriever = new ObjectRetriever([
            'static_object_directory' => $directory,
        ]);
        $this->setMockResponse(new Response(200, ['Content-Type' => 'application/ld+json'],
            '{"@id":"coid://cloudobjects.io/Other","http://www.w3.org/2000/01/rdf-schema#label":"API"}'));

        try {
            $object = $this->retriever->getObjectNode(new IRI('coid://cloudobjects.io/Other'));
            $this->assertEquals('API', $object->getProperty('http://www.w3.org/2000/01/rdf-schema#label')->getValue());
        } finally {
            $this->removeDirectory($directory);
        }
    }

}