Create a customized myers diff based system for snip content

deploy.php

@@ -3,6 +3,7 @@
 namespace Deployer;
 
 require_once 'recipe/common.php';
+require_once 'deploy/git.php';
 
 // Project name
 set('application', 'snips');
@@ -13,82 +14,48 @@ set('repository', 'git@git.loken.nl:ardent/Snips.git');
 // [Optional] Allocate tty for git clone. Default value is false.
 set('git_tty', true);
 
-// Shared files/dirs between deploys 
+// Shared files/dirs between deploys
 set('shared_dirs', ['var/log', 'var/sessions']);
 set('shared_files', ['.env.local']);
 //set('writable_dirs', ['var']);
+
 set('migrations_config', '');
 set('allow_anonymous_stats', false);
 
+set('console_options', fn() => '--no-interaction');
+set('bin/console', fn() => parse('{{release_path}}/bin/console'));
+
 // Hosts
 host('snips.loken.nl')
     ->setRemoteUser('www-data')
     ->set('branch', function () {
         return input()->getOption('branch') ?: 'master';
     })
-    ->set('deploy_path', '~/snips.loken.nl');
+    ->set('deploy_path', '~/snips.loken.nl')
-
+;
-set('bin/console', function () {
-    return parse('{{release_path}}/bin/console');
-});
-
-set('console_options', function () {
-    return '--no-interaction';
-});
 
 desc('Clear cache');
-task('cache:clear', function () {
+task('cache:clear', fn() => run('{{bin/php}} {{bin/console}} cache:clear {{console_options}} --no-warmup'));
-    run('{{bin/php}} {{bin/console}} cache:clear {{console_options}} --no-warmup');
-});
 
 desc('Warm up cache');
-task('cache:warmup', function () {
+task('cache:warmup', fn() => run('{{bin/php}} {{bin/console}} cache:warmup {{console_options}}'));
-    run('{{bin/php}} {{bin/console}} cache:warmup {{console_options}}');
-});
 
 desc('Migrate database');
 task('database:migrate', function () {
-//    $options = '--allow-no-migration';
+    $options = '--allow-no-migration';
-//    if (get('migrations_config') !== '') {
+    if (get('migrations_config') !== '') {
-//        $options = sprintf('%s --configuration={{release_path}}/{{migrations_config}}', $options);
+        $options = sprintf('%s --configuration={{release_path}}/{{migrations_config}}', $options);
-//    }
+    }
-//
+
-//    run(sprintf('{{bin/php}} {{bin/console}} doctrine:migrations:migrate %s {{console_options}}', $options));
+    run(sprintf('{{bin/php}} {{bin/console}} doctrine:migrations:migrate %s {{console_options}}', $options));
-    run('{{bin/php}} {{bin/console}} doctrine:schema:update --force');
 });
 
-task('deployment:log', function () { //https://stackoverflow.com/questions/59686270/how-to-log-deployments-in-deployer
+desc('Shows current deployed version');
-    $branch = parse('{{branch}}');
+task('deploy:current', function () {
-    $date = date('Y-m-d H:i:s');
+    $current = run('readlink {{deploy_path}}/current');
-    $commitHashShort = runLocally('git rev-parse --short HEAD');
+    writeln("Current deployed version: $current");
-//    $commitHash = runLocally('git rev-parse HEAD');
-    $commit = explode(PHP_EOL, runLocally('git log -1 --pretty="%H%n%ci"'));
-    $commitHash = $commit[0];
-    $commitDate = $commit[1];
-
-//    $line = sprintf('%s %s branch="%s" hash="%s"', $date, $commitHashShort, $branch, $commitHash);
-    $projectUrlBase = 'https://git.loken.nl/ardent/Snips';
-    $array = [
-        'branch' => $branch,
-        'branchUrl' => sprintf('%s/src/branch/%s', $projectUrlBase, $branch),
-        'date' => $date,
-        'commitHashShort' => $commitHashShort,
-        'commitHashLong' => $commitHash,
-        'commitDate' => $commitDate,
-        'commitUrl' => sprintf('%s/commit/%s', $projectUrlBase, $commitHash),
-        'projectUrl' => $projectUrlBase,
-    ];
-    $json = json_encode($array, JSON_PRETTY_PRINT);
-
-    runLocally("echo '$json' > release.json");
-    upload('release.json', '{{release_path}}/release.json');
 });
 
-//desc('Deploy project');
-//task('deploy', [
-//    'deployment:log',
-//]);
-
 desc('Deploy project');
 task('deploy', [
     'deploy:prepare',
@@ -100,9 +67,9 @@ task('deploy', [
     'deploy:symlink',
     'deploy:unlock',
     'deploy:cleanup',
+    'deploy:current',
 ]);
 
 after('deploy', 'deploy:success');
 
-// [Optional] if deploy fails automatically unlock.
+after('deploy:failed', 'deploy:unlock');
-after('deploy:failed', 'deploy:unlock');

deploy/git.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace Deployer;
+
+desc('Transfers information about current git commit to server');
+task('deployment:log', function () { //https://stackoverflow.com/questions/59686270/how-to-log-deployments-in-deployer
+    $branch = parse('{{branch}}');
+    $date = date('Y-m-d H:i:s');
+    $commitHashShort = runLocally('git rev-parse --short HEAD');
+//    $commitHash = runLocally('git rev-parse HEAD');
+    $commit = explode(PHP_EOL, runLocally('git log -1 --pretty="%H%n%ci"'));
+    $commitHash = $commit[0];
+    $commitDate = $commit[1];
+
+//    $line = sprintf('%s %s branch="%s" hash="%s"', $date, $commitHashShort, $branch, $commitHash);
+    $array = [
+        'branch' => $branch,
+        'date' => $date,
+        'commitHashShort' => $commitHashShort,
+        'commitHashLong' => $commitHash,
+        'commitDate' => $commitDate,
+    ];
+    $json = json_encode($array, JSON_PRETTY_PRINT);
+
+    runLocally("echo '$json' > release.json");
+    upload('release.json', '{{release_path}}/release.json');
+});

src/Controller/SnipController.php

@@ -7,8 +7,8 @@ use App\Form\ConfirmationType;
 use App\Form\SnipType;
 use App\Repository\SnipRepository;
 use App\Security\Voter\SnipVoter;
+use App\Service\SnipContent\SnipContentService;
 use App\Service\SnipParser\Pipeline;
-use App\Service\SnipServiceFactory;
 use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
 use Symfony\Component\Form\Extension\Core\Type\SubmitType;
 use Symfony\Component\HttpFoundation\Request;
@@ -20,10 +20,8 @@ class SnipController extends AbstractController
 {
     public function __construct(
         private readonly SnipRepository     $repository,
-        private readonly SnipServiceFactory $snipServiceFactory,
+        private readonly SnipContentService $contentService,
-    )
+    ) {}
-    {
-    }
 
     #[Route('/', name: '_index')]
     public function index(): Response
@@ -48,11 +46,9 @@ class SnipController extends AbstractController
     {
         $this->denyAccessUnlessGranted(SnipVoter::VIEW, $snip);
 
-        $snipService = $this->snipServiceFactory->create($snip);
-
         return $this->render('snip/single.html.twig', [
             'snip' => $snip,
-            'content' => $pl->parse($snipService->getActiveText()),
+            'content' => $pl->parse($this->contentService->getActiveText($snip)),
         ]);
     }
 
@@ -62,7 +58,7 @@ class SnipController extends AbstractController
         $this->denyAccessUnlessGranted(SnipVoter::VIEW, $snip);
 
         $response = new Response(
-            $pl->clean($this->snipServiceFactory->create($snip)->getActiveText()),
+            $pl->clean($this->contentService->getActiveText($snip)),
             Response::HTTP_OK,
             ['Content-Type' => 'text/html']
         );
@@ -70,7 +66,8 @@ class SnipController extends AbstractController
             ->setVary(['Accept', 'Accept-Encoding'])
             ->setEtag(md5($response->getContent()))
             ->setTtl(3600)
-            ->setClientTtl(300);
+            ->setClientTtl(300)
+        ;
 
         if (!$request->isNoCache()) {
             $response->isNotModified($request);
@@ -87,13 +84,13 @@ class SnipController extends AbstractController
         $form = $this->createForm(SnipType::class, $snip);
         $form->add('Save', SubmitType::class);
         if ($snip->getId()) {
-            $form->get('content')->setData($this->snipServiceFactory->create($snip)->getActiveText());
+            $form->get('content')->setData($this->contentService->getActiveText($snip));
         }
 
         $form->handleRequest($request);
         if ($form->isSubmitted() && $form->isValid()) {
             $this->repository->save($snip);
-            $this->snipServiceFactory->create($snip)->update($form->get('content')->getData());
+            $this->contentService->update($snip, $form->get('content')->getData());
 
             $this->addFlash('success', sprintf('Snip "%s" saved', $snip));
 
@@ -113,7 +110,8 @@ class SnipController extends AbstractController
     {
         $snip = new Snip();
         $snip->setCreatedAtNow()
-            ->setCreatedBy($this->getUser());
+             ->setCreatedBy($this->getUser())
+        ;
 
         return $this->edit($snip, $request);
     }
@@ -126,7 +124,7 @@ class SnipController extends AbstractController
         $form = $this->createForm(ConfirmationType::class);
         $form->handleRequest($request);
         if ($form->isSubmitted() && $form->isValid()) {
-            $this->snipServiceFactory->create($snip)->delete();
+            $this->contentService->delete($snip);
             $this->repository->remove($snip);
             $this->addFlash('success', sprintf('Snip "%s" deleted', $snip));
             return $this->redirectToRoute('snip_index');

src/Controller/VersionController.php

@@ -5,7 +5,7 @@ namespace App\Controller;
 use App\Entity\Snip;
 use App\Entity\SnipContent;
 use App\Security\Voter\SnipVoter;
-use App\Service\SnipServiceFactory;
+use App\Service\SnipContent\SnipContentService;
 use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\Routing\Attribute\Route;
@@ -14,7 +14,7 @@ use Symfony\Component\Routing\Attribute\Route;
 class VersionController extends AbstractController
 {
     public function __construct(
-        private readonly SnipServiceFactory $snipServiceFactory,
+        private readonly SnipContentService $contentService,
     ) {}
 
     #[Route('/', name: '_index')]
@@ -32,7 +32,7 @@ class VersionController extends AbstractController
     {
         $this->denyAccessUnlessGranted(SnipVoter::EDIT, $snip);
 
-        $this->snipServiceFactory->create($snip)->setVersion($version);
+        $this->contentService->setVersion($snip, $version);
         $this->addFlash('success', 'Snip version set to ' . $version->getId());
         return $this->redirectToRoute('snip_single', ['snip' => $snip->getId()]);
     }

src/Entity/SnipContent.php

@@ -32,6 +32,9 @@ class SnipContent
     #[ORM\Column(type: Types::TEXT, nullable: true)]
     private ?string $text = null;
 
+    #[ORM\Column(nullable: true)]
+    private ?array $diff = null;
+
     public function __construct()
     {
         $this->children = new ArrayCollection();
@@ -107,4 +110,16 @@ class SnipContent
 
         return $this;
     }
+
+    public function getDiff(): ?array
+    {
+        return $this->diff;
+    }
+
+    public function setDiff(?array $diff): static
+    {
+        $this->diff = $diff;
+
+        return $this;
+    }
 }

src/Service/SnipContent/MyersDiff.php

@@ -0,0 +1,171 @@
+<?php
+
+namespace App\Service\SnipContent;
+
+class MyersDiff
+{
+    private const string NEWLINE = "\r\n";
+
+    /**
+     * Backtrack through the intermediate results to extract the "snakes" that
+     * are visited on the chosen "D-path".
+     *
+     * @param string[] $v_save Intermediate results
+     * @param int      $x End position
+     * @param int      $y End position
+     *
+     * @return int[][]
+     */
+    private static function extractSnakes(array $v_save, int $x, int $y): array
+    {
+        $snakes = [];
+        for ($d = count($v_save) - 1; $x >= 0 && $y >= 0; $d--) {
+            array_unshift($snakes, [$x, $y]);
+
+            $v = $v_save[$d];
+            $k = $x - $y;
+
+            if ($k === -$d || $k !== $d && $v[$k - 1] < $v[$k + 1]) {
+                $k_prev = $k + 1;
+            } else {
+                $k_prev = $k - 1;
+            }
+
+            $x = $v[$k_prev];
+            $y = $x - $k_prev;
+        }
+
+        return $snakes;
+    }
+
+    private static function formatCompact(array $snakes, array $b): array
+    {
+        $solution = [];
+        $x = 0;
+        $y = 0;
+
+        foreach ($snakes as $snake) {
+            // Deletions
+            while ($snake[0] - $snake[1] > $x - $y) {
+                $count = 0;
+                while ($snake[0] - $snake[1] > $x - $y) {
+                    $x++;
+                    $count++;
+                }
+                $solution[] = ['D', $count];
+            }
+
+            // Insertions
+            while ($snake[0] - $snake[1] < $x - $y) {
+                $values = [];
+                while ($snake[0] - $snake[1] < $x - $y) {
+                    $values[] = $b[$y];
+                    $y++;
+                }
+                if ($solution[count($solution) - 1][0] === 'I') {
+                    $solution[count($solution) - 1][1] = array_merge($solution[count($solution) - 1][1], $values);
+                } else {
+                    $solution[] = ['I', $values];
+                }
+            }
+
+            // Keeps (snake diagonals)
+            $count = 0;
+            while ($x < $snake[0]) {
+                $x++;
+                $y++;
+                $count++;
+            }
+            if ($count > 0) {
+                $solution[] = ['K', $count];
+            }
+        }
+
+        return $solution;
+    }
+
+    /**
+     * Calculate the shortest edit sequence to convert $x into $y.
+     *
+     * @param string    $textFrom - tokens (characters, words or lines)
+     * @param string    $textTo - tokens (characters, words or lines)
+     * @param ?callable $compare - comparison function for tokens. Signature is compare($x, $y):bool. If null, === is used.
+     *
+     * @return array[] - pairs of token and edit (-1 for delete, 0 for keep, +1 for insert)
+     */
+    public static function calculate(string $textFrom, string $textTo, ?callable $compare = null): array
+    {
+        $a = self::explode($textFrom);
+        $b = self::explode($textTo);
+
+        if ($compare === null) {
+            $compare = function ($x, $y) {
+                return $x === $y;
+            };
+        }
+
+        $n = count($a);
+        $m = count($b);
+        $a = array_values($a);
+        $b = array_values($b);
+        $max = $m + $n;
+
+        $v_save = [];
+
+        $v = [1 => 0];
+        for ($d = 0; $d <= $max; $d++) {
+            for ($k = -$d; $k <= $d; $k += 2) {
+                if ($k === -$d || $k !== $d && $v[$k - 1] < $v[$k + 1]) {
+                    $x = $v[$k + 1];
+                } else {
+                    $x = $v[$k - 1] + 1;
+                }
+                $y = $x - $k;
+                while ($x < $n && $y < $m && $compare($a[$x], $b[$y])) {
+                    $x++;
+                    $y++;
+                }
+                $v[$k] = $x;
+                $v_save[$d] = $v;
+                if ($x === $n && $y === $m) {
+                    break 2;
+                }
+            }
+        }
+
+        return self::formatCompact(self::extractSnakes($v_save, $n, $m), $b);
+    }
+
+    public static function rebuildBFromCompact(string $textFrom, array $diff): string
+    {
+        $a = self::explode($textFrom);
+        $b = [];
+        $x = 0;
+
+        foreach ($diff as [$op, $data]) {
+            if ($op === 'K') {
+                for ($i = 0; $i < $data; $i++) {
+                    $b[] = $a[$x++];
+                }
+            } elseif ($op === 'D') {
+                $x += $data; // skip deleted
+            } elseif ($op === 'I') {
+                foreach ($data as $v) {
+                    $b[] = $v;
+                }
+            }
+        }
+
+        return self::implode($b);
+    }
+
+    private static function explode(string $text): array
+    {
+        return explode(self::NEWLINE, $text);
+    }
+
+    private static function implode(array $text): string
+    {
+        return implode(self::NEWLINE, $text);
+    }
+}

src/Service/SnipContent/SnipContentService.php

@@ -8,49 +8,96 @@ use Doctrine\ORM\EntityManagerInterface;
 
 readonly class SnipContentService
 {
+
     public function __construct(
-        private Snip                   $snip,
         private EntityManagerInterface $em,
     ) {}
 
-    public function update(string $snipContents): void
+    public function update(Snip $snip, string $snipContents): void
     {
-        if ($this->snip->getActiveVersion()?->getText() === $snipContents) {
+        $parentContent = $snip->getActiveVersion();
+        if ($this->rebuildText($parentContent) === $snipContents) {
             return;
         }
+
         // Create new snipContent entity with previous one as parent
         $content = new SnipContent();
         $content
             ->setText($snipContents)
-            ->setSnip($this->snip)
+            ->setSnip($snip)
         ;
-        if ($this->snip->getActiveVersion() !== null) {
+        if ($parentContent !== null) {
-            $content->setParent($this->snip->getActiveVersion());
+            $content->setParent($parentContent);
+            $this->contentToRelative($parentContent);
         }
 
         $this->em->persist($content);
         $this->em->flush();
 
-        $this->snip->setActiveVersion($content);
+        $snip->setActiveVersion($content);
-        $this->em->persist($this->snip);
+        $this->em->persist($snip);
         $this->em->flush();
     }
 
-    // Shortcut to get the active text
+    public function getActiveText(Snip $snip): string
-    public function getActiveText(): string
     {
         $contentRepo = $this->em->getRepository(SnipContent::class);
-        return $contentRepo->find($this->snip->getActiveVersion())->getText();
+        return $this->rebuildText($contentRepo->find($snip->getActiveVersion()));
     }
 
-    public function setVersion(SnipContent $version): void
+    public function rebuildText(SnipContent $snipContent): string
     {
-        $this->snip->setActiveVersion($version);
+        if ($snipContent->getText()) {
-        $this->em->persist($this->snip);
+            return $snipContent->getText();
+        }
+
+        $parentContent = $snipContent->getParent();
+        if ($parentContent === null && $snipContent->getDiff() === null) {
+            return '---Something went very wrong, cant rebuild the text---';
+        }
+
+        return MyersDiff::rebuildBFromCompact(
+            $this->rebuildText($parentContent), $snipContent->getDiff()
+        );
+    }
+
+    public function setVersion(Snip $snip, SnipContent $version): void
+    {
+        $activeVersion = $snip->getActiveVersion();
+        $this->contentToAbsolute($version);
+        $this->contentToRelative($activeVersion);
+
+        $snip->setActiveVersion($version);
+        $this->em->persist($snip);
         $this->em->flush();
     }
 
-    public function delete(): void
+    public function contentToRelative(SnipContent $content): void
+    {
+        if ($content->getText() === null || $content->getParent() === null) {
+            return;
+        }
+        $contentText = $content->getText();
+        $parentText = $this->rebuildText($content->getParent());
+        $diff = MyersDiff::calculate($parentText, $contentText);
+        $content->setDiff($diff);
+        $content->setText(null);
+        $this->em->persist($content);
+        $this->em->flush();
+    }
+
+    public function contentToAbsolute(SnipContent $content): void
+    {
+        if ($content->getDiff() === null) {
+            return;
+        }
+        $content->setText($this->rebuildText($content));
+        $content->setDiff(null);
+        $this->em->persist($content);
+        $this->em->flush();
+    }
+
+    public function delete(Snip $snip): void
     {
         // Cleanup the versions
     }

src/Service/SnipParser/Stages/IncludeReferenceStage.php

@@ -5,6 +5,7 @@ namespace App\Service\SnipParser\Stages;
 use App\Repository\SnipContentRepository;
 use App\Repository\SnipRepository;
 use App\Security\Voter\SnipVoter;
+use App\Service\SnipContent\SnipContentService;
 use App\Service\SnipParser\Pipeline;
 use League\Pipeline\StageInterface;
 use Symfony\Bundle\SecurityBundle\Security;
@@ -17,6 +18,7 @@ class IncludeReferenceStage implements StageInterface
         #[Autowire(lazy: true)] private readonly SnipRepository        $snipRepository,
         #[Autowire(lazy: true)] private readonly SnipContentRepository $snipContentRepository,
         #[Autowire(lazy: true)] private readonly Pipeline              $pipeline,
+        #[Autowire(lazy: true)] private readonly SnipContentService    $snipContentService,
     ) {}
 
     public function __invoke(mixed $payload): string
@@ -51,7 +53,9 @@ class IncludeReferenceStage implements StageInterface
                 return sprintf('<span title="access denied">%s</span>', $matches[0]);
             }
 
-            return $this->pipeline->parse($content->getText());
+            return $this->pipeline->parse(
+                $this->snipContentService->rebuildText($content)
+            );
         }, $payload);
     }
 }