Feature/publication validation

[dxL1nus]

Closes #12,
closes #122,
closes #143,
closes #144,
closes #145,
closes #146

!!! Firstly please look at the issue listed above, to see exactly which features this PR introduces.

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This PR introduces the CodecheckPublicationValidator.php which validates things like the CODECHECK status, the produced codecheck.yml file and more.

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I reworked the Settings Form UI a bit as well in this PR, to group together related settings (e.g. Settings concerning the GitHub Register, or settings concerning the Submission stage, or settings concerning the publication validation stage).

[nuest]

I have just one critical point about a validation function, maybe it must be renamed.

Minor things re. this PR added to a follow-up issue for later, to not hold this merging up: #148

[nuest]

This validation function seems never to return true anymore.

[dxL1nus]

Ohhh now I see what you mean. No that is actually down to something completely different and intended.
It is down to how OJS handles hooks. The publication will be invalid, whenever we ship at least one error in the $errors Array. And it will be valid, whenever the array is empty.

The return value of this function doesn't have to do anything with the publication validation. Instead it has to do with how OJS handles this hook. If true where to be returned, the Hook: 'Publication::validatePublish' would stop to be called (meaning that for other plugins & OJS itsself this Hook wouldn't be fired anymore, if we have invalid metadata). This of course means, that e.g. if a submission is in the review stage, but somehow the editor already wants to publish it, we never get to see this error during the publication validation (because our invalid CODECHECK data would stop the hook).

To prevent this, it is best practise to always return false on a Hook, so other Plugins and OJS itsself get to call the Hook as well after our plugin did.

[nuest]

Please document this in the function documentation then (a one line comment next to the "return false" also makes sense), and rename the function also, maybe end it in ...Hook ?

Then it is clear that the return value is not about the validation result but about the processing of the hook;

[dxL1nus]

How it looks now:

/**
 * The publication will be invalid, whenever we ship at least one error in the `$errors` Array. And it will be valid, whenever the array is empty.
 * The return value of this function doesn't have to do anything with the publication validation. Instead it has to do with how OJS handles this hook. If `true` where to be returned, the Hook: `'Publication::validatePublish'` would stop to be called (meaning that for other plugins & OJS itsself this Hook wouldn't be fired anymore, if we have invalid metadata). This of course means, that e.g. if a submission is in the review stage, but somehow the editor already wants to publish it, we never get to see this error during the publication validation (because our invalid CODECHECK data would stop the hook).
 * To prevent this, it is best practise to always return `false` on a Hook, so other Plugins and OJS itsself get to call the Hook as well after our plugin did.
 * 
 * @param string $hookName The name of the Hook (`'Publication::validatePublish'`)
 * @param array $args The arguments of the Hook including the validation `$errors` Array at `&$args[0]`
 * 
 * @return bool Returns `false` to enable OJS itsself and other Plugins to continue with their implementation for this Hook
*/
public function validatePublicationHook(string $hookName, array $args): bool
{
    CodecheckLogger::debug("Validating Publication!");
    $errors = &$args[0];
    $codecheckPublicationValidator = new CodecheckPublicationValidator($this);

    $validationErrors = $codecheckPublicationValidator->validatePublication();

    if(is_array($validationErrors)) {
        $errors = array_merge($errors, $validationErrors);
    }

    /* Returns `false` to enable OJS itsself and other Plugins to continue with their implementation for this Hook */
    return false;
}