versioning-command-idea.php

<?php

class ChangeStationScheduleSettings implements Command // Implement 'isVersionableProperty' or something???
{
    private string $stationId;
    private bool $isEnabled;

    public function __construct(string $stationId, bool $isEnabled)
    {
        $this->stationId = $stationId;
        $this->isEnabled = $isEnabled;
    }
    
    // Getters
}

class PublishDraft implements Command
{
}

class App
{
    // All the other attributes
    // ...
    
    private string $revisionState;
    private array $commands = [];
    
    private function startADraft()
    {
        $this->revisionState = 'draft';
    }
    
    public function handle(Command $command)
    {
        if($this->getRevisionState() === 'draft') {
            $this->persistCommand($command);
            return;
        }
        
        if($this->state !== 'design') { // We're not at the design stage. Better start a draft
            $this->startADraft();
            $this->handle($command);
            return;
        }

        $this->handleCommand($command); // State is something else. Just apply the changes
    }

    private function handleCommand(Command $command)
    {
        if($command instanceof ChangeStationScheduleSettings) {
            $this->handleStationScheduleChangeCommand($command);
        }
        
        if($command instanceof PublishDraft) {
            $this->revisionState = 'published'; // publish??? An intermediate state??
        }
        
        // Other handlers here
    }

    public function handleStationScheduleChangeCommand(ChangeStationScheduleCommand $command)
    {
        $appStation = $this->stations->get($command->getStationId());
        $appStation->setScheduleSettings(new AppStationScheduleSettings($command->isEnabled()));
    }

    private function persistCommand(Command $command)
    {
        $this->commands[] = $command;
    }

    public function applyCommands()
    {
        foreach ($this->commands as $command) {
            $this->handleCommand($command);
        }
    }
    
    public function purgeCommands()
    {
        $this->commands = [];
    }
}

class AppRepository
{
    public function getPublishedVersion(string $appId): ?App // The currently published version with no changes
    {
        $app = $this->em->findById($appId);
        return $app;
    }

    public function getLatestVersion(string $appId): ?App // The draft version. Could be the same as above???
    {
        $app = $this->em->findById($appId);
        $app->applyCommands();
        return $app;
    }
    
    public function save(App $app)
    {
        $this->em->persist($app);
        $this->em->flush();
    }
    
    public function saveAndPublish(App $app) // A good idea doing this here??
    {
        $app->handle(new PublishDraft());
        $app->applyCommands();
        $app->purgeCommands();
        $this->save($app);
    }
}