HTMLForm.php

Go to the documentation of this file.

<?php
 
use MediaWiki\HookContainer\ProtectedHookAccessorTrait;
use MediaWiki\Linker\LinkTarget;
use MediaWiki\MainConfigNames;
use MediaWiki\Page\PageReference;
 
class HTMLForm extends ContextSource {
    use ProtectedHookAccessorTrait;
 
    public static $typeMappings = [
        'api' => HTMLApiField::class,
        'text' => HTMLTextField::class,
        'textwithbutton' => HTMLTextFieldWithButton::class,
        'textarea' => HTMLTextAreaField::class,
        'select' => HTMLSelectField::class,
        'combobox' => HTMLComboboxField::class,
        'radio' => HTMLRadioField::class,
        'multiselect' => HTMLMultiSelectField::class,
        'limitselect' => HTMLSelectLimitField::class,
        'check' => HTMLCheckField::class,
        'toggle' => HTMLCheckField::class,
        'int' => HTMLIntField::class,
        'file' => HTMLFileField::class,
        'float' => HTMLFloatField::class,
        'info' => HTMLInfoField::class,
        'selectorother' => HTMLSelectOrOtherField::class,
        'selectandother' => HTMLSelectAndOtherField::class,
        'namespaceselect' => HTMLSelectNamespace::class,
        'namespaceselectwithbutton' => HTMLSelectNamespaceWithButton::class,
        'tagfilter' => HTMLTagFilter::class,
        'sizefilter' => HTMLSizeFilterField::class,
        'submit' => HTMLSubmitField::class,
        'hidden' => HTMLHiddenField::class,
        'edittools' => HTMLEditTools::class,
        'checkmatrix' => HTMLCheckMatrix::class,
        'cloner' => HTMLFormFieldCloner::class,
        'autocompleteselect' => HTMLAutoCompleteSelectField::class,
        'language' => HTMLSelectLanguageField::class,
        'date' => HTMLDateTimeField::class,
        'time' => HTMLDateTimeField::class,
        'datetime' => HTMLDateTimeField::class,
        'expiry' => HTMLExpiryField::class,
        // HTMLTextField will output the correct type="" attribute automagically.
        // There are about four zillion other HTML5 input types, like range, but
        // we don't use those at the moment, so no point in adding all of them.
        'email' => HTMLTextField::class,
        'password' => HTMLTextField::class,
        'url' => HTMLTextField::class,
        'title' => HTMLTitleTextField::class,
        'user' => HTMLUserTextField::class,
        'tagmultiselect' => HTMLTagMultiselectField::class,
        'usersmultiselect' => HTMLUsersMultiselectField::class,
        'titlesmultiselect' => HTMLTitlesMultiselectField::class,
        'namespacesmultiselect' => HTMLNamespacesMultiselectField::class,
    ];
 
    public $mFieldData;
 
    protected $mMessagePrefix;
 
    protected $mFlatFields = [];
    protected $mFieldTree = [];
    protected $mShowReset = false;
    protected $mShowSubmit = true;
    protected $mSubmitFlags = [ 'primary', 'progressive' ];
    protected $mShowCancel = false;
    protected $mCancelTarget;
 
    protected $mSubmitCallback;
    protected $mValidationErrorMessage;
 
    protected $mPre = '';
    protected $mHeader = '';
    protected $mFooter = '';
    protected $mSectionHeaders = [];
    protected $mSectionFooters = [];
    protected $mPost = '';
    protected $mId;
    protected $mName;
    protected $mTableId = '';
 
    protected $mSubmitID;
    protected $mSubmitName;
    protected $mSubmitText;
    protected $mSubmitTooltip;
 
    protected $mFormIdentifier;
    protected $mTitle;
    protected $mMethod = 'post';
    protected $mWasSubmitted = false;
 
    protected $mAction = false;
 
    protected $mCollapsible = false;
 
    protected $mCollapsed = false;
 
    protected $mAutocomplete = null;
 
    protected $mUseMultipart = false;
    protected $mHiddenFields = [];
    protected $mButtons = [];
 
    protected $mWrapperLegend = false;
    protected $mWrapperAttributes = [];
 
    protected $mTokenSalt = '';
 
    protected $mSubSectionBeforeFields = true;
 
    protected $displayFormat = 'table';
 
    protected $availableDisplayFormats = [
        'table',
        'div',
        'raw',
        'inline',
    ];
 
    protected $availableSubclassDisplayFormats = [
        'vform',
        'ooui',
    ];
 
    private $hiddenTitleAddedToForm = false;
 
    public static function factory(
        $displayFormat, $descriptor, IContextSource $context, $messagePrefix = ''
    ) {
        switch ( $displayFormat ) {
            case 'vform':
                return new VFormHTMLForm( $descriptor, $context, $messagePrefix );
            case 'ooui':
                return new OOUIHTMLForm( $descriptor, $context, $messagePrefix );
            default:
                $form = new self( $descriptor, $context, $messagePrefix );
                $form->setDisplayFormat( $displayFormat );
                return $form;
        }
    }
 
    public function __construct(
        $descriptor, IContextSource $context, $messagePrefix = ''
    ) {
        $this->setContext( $context );
        $this->mMessagePrefix = $messagePrefix;
 
        // Evil hack for mobile :(
        if (
            !$this->getConfig()->get( MainConfigNames::HTMLFormAllowTableFormat )
            && $this->displayFormat === 'table'
        ) {
            $this->displayFormat = 'div';
        }
 
        $this->addFields( $descriptor );
    }
 
    public function addFields( $descriptor ) {
        $loadedDescriptor = [];
 
        foreach ( $descriptor as $fieldname => $info ) {
 
            $section = $info['section'] ?? '';
 
            if ( isset( $info['type'] ) && $info['type'] === 'file' ) {
                $this->mUseMultipart = true;
            }
 
            $field = static::loadInputFromParameters( $fieldname, $info, $this );
 
            $setSection =& $loadedDescriptor;
            if ( $section ) {
                foreach ( explode( '/', $section ) as $newName ) {
                    if ( !isset( $setSection[$newName] ) ) {
                        $setSection[$newName] = [];
                    }
 
                    $setSection =& $setSection[$newName];
                }
            }
 
            $setSection[$fieldname] = $field;
            $this->mFlatFields[$fieldname] = $field;
        }
 
        $this->mFieldTree = array_merge( $this->mFieldTree, $loadedDescriptor );
 
        return $this;
    }
 
    public function hasField( $fieldname ) {
        return isset( $this->mFlatFields[$fieldname] );
    }
 
    public function getField( $fieldname ) {
        if ( !$this->hasField( $fieldname ) ) {
            throw new DomainException( __METHOD__ . ': no field named ' . $fieldname );
        }
        return $this->mFlatFields[$fieldname];
    }
 
    public function setDisplayFormat( $format ) {
        if (
            in_array( $format, $this->availableSubclassDisplayFormats, true ) ||
            in_array( $this->displayFormat, $this->availableSubclassDisplayFormats, true )
        ) {
            throw new MWException( 'Cannot change display format after creation, ' .
                'use HTMLForm::factory() instead' );
        }
 
        if ( !in_array( $format, $this->availableDisplayFormats, true ) ) {
            throw new MWException( 'Display format must be one of ' .
                print_r(
                    array_merge(
                        $this->availableDisplayFormats,
                        $this->availableSubclassDisplayFormats
                    ),
                    true
                ) );
        }
 
        // Evil hack for mobile :(
        if ( !$this->getConfig()->get( MainConfigNames::HTMLFormAllowTableFormat ) &&
        $format === 'table' ) {
            $format = 'div';
        }
 
        $this->displayFormat = $format;
 
        return $this;
    }
 
    public function getDisplayFormat() {
        return $this->displayFormat;
    }
 
    public static function getClassFromDescriptor( $fieldname, &$descriptor ) {
        if ( isset( $descriptor['class'] ) ) {
            $class = $descriptor['class'];
        } elseif ( isset( $descriptor['type'] ) ) {
            $class = static::$typeMappings[$descriptor['type']];
            $descriptor['class'] = $class;
        } else {
            $class = null;
        }
 
        if ( !$class ) {
            throw new MWException( "Descriptor with no class for $fieldname: "
                . print_r( $descriptor, true ) );
        }
 
        return $class;
    }
 
    public static function loadInputFromParameters( $fieldname, $descriptor,
        HTMLForm $parent = null
    ) {
        $class = static::getClassFromDescriptor( $fieldname, $descriptor );
 
        $descriptor['fieldname'] = $fieldname;
        if ( $parent ) {
            $descriptor['parent'] = $parent;
        }
 
        # @todo This will throw a fatal error whenever someone try to use
        # 'class' to feed a CSS class instead of 'cssclass'. Would be
        # great to avoid the fatal error and show a nice error.
        return new $class( $descriptor );
    }
 
    public function prepareForm() {
        # Load data from the request.
        if (
            $this->mFormIdentifier === null ||
            $this->getRequest()->getVal( 'wpFormIdentifier' ) === $this->mFormIdentifier
        ) {
            $this->loadFieldData();
        } else {
            $this->mFieldData = [];
        }
 
        return $this;
    }
 
    public function tryAuthorizedSubmit() {
        $result = false;
 
        if ( $this->mFormIdentifier === null ) {
            $identOkay = true;
        } else {
            $identOkay = $this->getRequest()->getVal( 'wpFormIdentifier' ) === $this->mFormIdentifier;
        }
 
        $tokenOkay = false;
        if ( $this->getMethod() !== 'post' ) {
            $tokenOkay = true; // no session check needed
        } elseif ( $this->getRequest()->wasPosted() ) {
            $editToken = $this->getRequest()->getVal( 'wpEditToken' );
            if ( $this->getUser()->isRegistered() || $editToken !== null ) {
                // Session tokens for logged-out users have no security value.
                // However, if the user gave one, check it in order to give a nice
                // "session expired" error instead of "permission denied" or such.
                $tokenOkay = $this->getUser()->matchEditToken( $editToken, $this->mTokenSalt );
            } else {
                $tokenOkay = true;
            }
        }
 
        if ( $tokenOkay && $identOkay ) {
            $this->mWasSubmitted = true;
            $result = $this->trySubmit();
        }
 
        return $result;
    }
 
    public function show() {
        $this->prepareForm();
 
        $result = $this->tryAuthorizedSubmit();
        if ( $result === true || ( $result instanceof Status && $result->isGood() ) ) {
            return $result;
        }
 
        $this->displayForm( $result );
 
        return false;
    }
 
    public function showAlways() {
        $this->prepareForm();
 
        $result = $this->tryAuthorizedSubmit();
 
        $this->displayForm( $result );
 
        return $result;
    }
 
    public function trySubmit() {
        $valid = true;
        $hoistedErrors = Status::newGood();
        if ( $this->mValidationErrorMessage ) {
            foreach ( $this->mValidationErrorMessage as $error ) {
                $hoistedErrors->fatal( ...$error );
            }
        } else {
            $hoistedErrors->fatal( 'htmlform-invalid-input' );
        }
 
        $this->mWasSubmitted = true;
 
        # Check for cancelled submission
        foreach ( $this->mFlatFields as $fieldname => $field ) {
            if ( !array_key_exists( $fieldname, $this->mFieldData ) ) {
                continue;
            }
            if ( $field->cancelSubmit( $this->mFieldData[$fieldname], $this->mFieldData ) ) {
                $this->mWasSubmitted = false;
                return false;
            }
        }
 
        # Check for validation
        foreach ( $this->mFlatFields as $fieldname => $field ) {
            if ( !array_key_exists( $fieldname, $this->mFieldData ) ) {
                continue;
            }
            if ( $field->isDisabled( $this->mFieldData ) ) {
                continue;
            }
            $res = $field->validate( $this->mFieldData[$fieldname], $this->mFieldData );
            if ( $res !== true ) {
                $valid = false;
                if ( $res !== false && !$field->canDisplayErrors() ) {
                    if ( is_string( $res ) ) {
                        $hoistedErrors->fatal( 'rawmessage', $res );
                    } else {
                        $hoistedErrors->fatal( $res );
                    }
                }
            }
        }
 
        if ( !$valid ) {
            return $hoistedErrors;
        }
 
        $callback = $this->mSubmitCallback;
        if ( !is_callable( $callback ) ) {
            throw new MWException( 'HTMLForm: no submit callback provided. Use ' .
                'setSubmitCallback() to set one.' );
        }
 
        $data = $this->filterDataForSubmit( $this->mFieldData );
 
        $res = call_user_func( $callback, $data, $this );
        if ( $res === false ) {
            $this->mWasSubmitted = false;
        } elseif ( $res instanceof StatusValue ) {
            // DWIM - callbacks are not supposed to return a StatusValue but it's easy to mix up.
            $res = Status::wrap( $res );
        }
 
        return $res;
    }
 
    public function wasSubmitted() {
        return $this->mWasSubmitted;
    }
 
    public function setSubmitCallback( $cb ) {
        $this->mSubmitCallback = $cb;
 
        return $this;
    }
 
    public function setValidationErrorMessage( $msg ) {
        $this->mValidationErrorMessage = $msg;
 
        return $this;
    }
 
    public function setIntro( $msg ) {
        return $this->setPreHtml( $msg );
    }
 
    public function setPreHtml( $html ) {
        $this->mPre = $html;
 
        return $this;
    }
 
    public function addPreHtml( $html ) {
        $this->mPre .= $html;
 
        return $this;
    }
 
    public function getPreHtml() {
        return $this->mPre;
    }
 
    public function setPreText( $msg ) {
        return $this->setPreHtml( $msg );
    }
 
    public function addPreText( $msg ) {
        return $this->addPreHtml( $msg );
    }
 
    public function getPreText() {
        return $this->getPreHtml();
    }
 
    public function addHeaderHtml( $html, $section = null ) {
        if ( $section === null ) {
            $this->mHeader .= $html;
        } else {
            if ( !isset( $this->mSectionHeaders[$section] ) ) {
                $this->mSectionHeaders[$section] = '';
            }
            $this->mSectionHeaders[$section] .= $html;
        }
 
        return $this;
    }
 
    public function setHeaderHtml( $html, $section = null ) {
        if ( $section === null ) {
            $this->mHeader = $html;
        } else {
            $this->mSectionHeaders[$section] = $html;
        }
 
        return $this;
    }
 
    public function getHeaderHtml( $section = null ) {
        if ( $section === null ) {
            return $this->mHeader;
        } else {
            return $this->mSectionHeaders[$section] ?? '';
        }
    }
 
    public function addHeaderText( $msg, $section = null ) {
        return $this->addHeaderHtml( $msg, $section );
    }
 
    public function setHeaderText( $msg, $section = null ) {
        return $this->setHeaderHtml( $msg, $section );
    }
 
    public function getHeaderText( $section = null ) {
        return $this->getHeaderHtml( $section );
    }
 
    public function addFooterHtml( $html, $section = null ) {
        if ( $section === null ) {
            $this->mFooter .= $html;
        } else {
            if ( !isset( $this->mSectionFooters[$section] ) ) {
                $this->mSectionFooters[$section] = '';
            }
            $this->mSectionFooters[$section] .= $html;
        }
 
        return $this;
    }
 
    public function setFooterHtml( $html, $section = null ) {
        if ( $section === null ) {
            $this->mFooter = $html;
        } else {
            $this->mSectionFooters[$section] = $html;
        }
 
        return $this;
    }
 
    public function getFooterHtml( $section = null ) {
        if ( $section === null ) {
            return $this->mFooter;
        } else {
            return $this->mSectionFooters[$section] ?? '';
        }
    }
 
    public function addFooterText( $msg, $section = null ) {
        return $this->addFooterHtml( $msg, $section );
    }
 
    public function setFooterText( $msg, $section = null ) {
        return $this->setFooterHtml( $msg, $section );
    }
 
    public function getFooterText( $section = null ) {
        return $this->getFooterHtml( $section );
    }
 
    public function addPostHtml( $html ) {
        $this->mPost .= $html;
 
        return $this;
    }
 
    public function setPostHtml( $html ) {
        $this->mPost = $html;
 
        return $this;
    }
 
    public function getPostHtml() {
        return $this->mPost;
    }
 
    public function addPostText( $msg ) {
        return $this->addPostHtml( $msg );
    }
 
    public function setPostText( $msg ) {
        return $this->setPostHtml( $msg );
    }
 
    public function addHiddenField( $name, $value, array $attribs = [] ) {
        $attribs += [ 'name' => $name ];
        $this->mHiddenFields[] = [ $value, $attribs ];
 
        return $this;
    }
 
    public function addHiddenFields( array $fields ) {
        foreach ( $fields as $name => $value ) {
            $this->mHiddenFields[] = [ $value, [ 'name' => $name ] ];
        }
 
        return $this;
    }
 
    public function addButton( $data ) {
        if ( !is_array( $data ) ) {
            $args = func_get_args();
            if ( count( $args ) < 2 || count( $args ) > 4 ) {
                throw new InvalidArgumentException(
                    'Incorrect number of arguments for deprecated calling style'
                );
            }
            $data = [
                'name' => $args[0],
                'value' => $args[1],
                'id' => $args[2] ?? null,
                'attribs' => $args[3] ?? null,
            ];
        } else {
            if ( !isset( $data['name'] ) ) {
                throw new InvalidArgumentException( 'A name is required' );
            }
            if ( !isset( $data['value'] ) ) {
                throw new InvalidArgumentException( 'A value is required' );
            }
        }
        $this->mButtons[] = $data + [
            'id' => null,
            'attribs' => null,
            'flags' => null,
            'framed' => true,
        ];
 
        return $this;
    }
 
    public function setTokenSalt( $salt ) {
        $this->mTokenSalt = $salt;
 
        return $this;
    }
 
    public function displayForm( $submitResult ) {
        $this->getOutput()->addHTML( $this->getHTML( $submitResult ) );
    }
 
    private function getHiddenTitle(): string {
        if ( $this->hiddenTitleAddedToForm ) {
            return '';
        }
 
        $html = '';
        if ( $this->getMethod() === 'post' ||
            $this->getAction() === $this->getConfig()->get( MainConfigNames::Script )
        ) {
            $html .= Html::hidden( 'title', $this->getTitle()->getPrefixedText() ) . "\n";
        }
        $this->hiddenTitleAddedToForm = true;
        return $html;
    }
 
    public function getHTML( $submitResult ) {
        # For good measure (it is the default)
        $this->getOutput()->setPreventClickjacking( true );
        $this->getOutput()->addModules( 'mediawiki.htmlform' );
        $this->getOutput()->addModuleStyles( 'mediawiki.htmlform.styles' );
 
        if ( $this->mCollapsible ) {
            // Preload jquery.makeCollapsible for mediawiki.htmlform
            $this->getOutput()->addModules( 'jquery.makeCollapsible' );
        }
 
        $html = ''
            . $this->getErrorsOrWarnings( $submitResult, 'error' )
            . $this->getErrorsOrWarnings( $submitResult, 'warning' )
            . $this->getHeaderText()
            . $this->getHiddenTitle()
            . $this->getBody()
            . $this->getHiddenFields()
            . $this->getButtons()
            . $this->getFooterText();
 
        $html = $this->wrapForm( $html );
 
        return '' . $this->mPre . $html . $this->mPost;
    }
 
    public function setCollapsibleOptions( $collapsedByDefault = false ) {
        $this->mCollapsible = true;
        $this->mCollapsed = $collapsedByDefault;
        return $this;
    }
 
    protected function getFormAttributes() {
        # Use multipart/form-data
        $encType = $this->mUseMultipart
            ? 'multipart/form-data'
            : 'application/x-www-form-urlencoded';
        # Attributes
        $attribs = [
            'class' => 'mw-htmlform',
            'action' => $this->getAction(),
            'method' => $this->getMethod(),
            'enctype' => $encType,
        ];
        if ( $this->mId ) {
            $attribs['id'] = $this->mId;
        }
        if ( is_string( $this->mAutocomplete ) ) {
            $attribs['autocomplete'] = $this->mAutocomplete;
        }
        if ( $this->mName ) {
            $attribs['name'] = $this->mName;
        }
        if ( $this->needsJSForHtml5FormValidation() ) {
            $attribs['novalidate'] = true;
        }
        return $attribs;
    }
 
    public function wrapForm( $html ) {
        # Include a <fieldset> wrapper for style, if requested.
        if ( $this->mWrapperLegend !== false ) {
            $legend = is_string( $this->mWrapperLegend ) ? $this->mWrapperLegend : false;
            $html = Xml::fieldset( $legend, $html, $this->mWrapperAttributes );
        }
 
        return Html::rawElement(
            'form',
            $this->getFormAttributes(),
            $html
        );
    }
 
    public function getHiddenFields() {
        $html = '';
 
        // add the title as a hidden file if it hasn't been added yet and if it is necessary
        // added for backward compatibility with the previous version of this public method
        $html .= $this->getHiddenTitle();
 
        if ( $this->mFormIdentifier !== null ) {
            $html .= Html::hidden(
                'wpFormIdentifier',
                $this->mFormIdentifier
            ) . "\n";
        }
        if ( $this->getMethod() === 'post' ) {
            $html .= Html::hidden(
                'wpEditToken',
                $this->getUser()->getEditToken( $this->mTokenSalt ),
                [ 'id' => 'wpEditToken' ]
            ) . "\n";
        }
 
        foreach ( $this->mHiddenFields as [ $value, $attribs ] ) {
            $html .= Html::hidden( $attribs['name'], $value, $attribs ) . "\n";
        }
 
        return $html;
    }
 
    public function getButtons() {
        $buttons = '';
        $useMediaWikiUIEverywhere =
            $this->getConfig()->get( MainConfigNames::UseMediaWikiUIEverywhere );
 
        if ( $this->mShowSubmit ) {
            $attribs = [];
 
            if ( isset( $this->mSubmitID ) ) {
                $attribs['id'] = $this->mSubmitID;
            }
 
            if ( isset( $this->mSubmitName ) ) {
                $attribs['name'] = $this->mSubmitName;
            }
 
            if ( isset( $this->mSubmitTooltip ) ) {
                $attribs += Linker::tooltipAndAccesskeyAttribs( $this->mSubmitTooltip );
            }
 
            $attribs['class'] = [ 'mw-htmlform-submit' ];
 
            if ( $useMediaWikiUIEverywhere ) {
                foreach ( $this->mSubmitFlags as $flag ) {
                    $attribs['class'][] = 'mw-ui-' . $flag;
                }
                $attribs['class'][] = 'mw-ui-button';
            }
 
            $buttons .= Xml::submitButton( $this->getSubmitText(), $attribs ) . "\n";
        }
 
        if ( $this->mShowReset ) {
            $buttons .= Html::element(
                'input',
                [
                    'type' => 'reset',
                    'value' => $this->msg( 'htmlform-reset' )->text(),
                    'class' => $useMediaWikiUIEverywhere ? 'mw-ui-button' : null,
                ]
            ) . "\n";
        }
 
        if ( $this->mShowCancel ) {
            $target = $this->getCancelTargetURL();
            $buttons .= Html::element(
                    'a',
                    [
                        'class' => $useMediaWikiUIEverywhere ? 'mw-ui-button' : null,
                        'href' => $target,
                    ],
                    $this->msg( 'cancel' )->text()
                ) . "\n";
        }
 
        foreach ( $this->mButtons as $button ) {
            $attrs = [
                'type' => 'submit',
                'name' => $button['name'],
                'value' => $button['value']
            ];
 
            if ( isset( $button['label-message'] ) ) {
                $label = $this->getMessage( $button['label-message'] )->parse();
            } elseif ( isset( $button['label'] ) ) {
                $label = htmlspecialchars( $button['label'] );
            } elseif ( isset( $button['label-raw'] ) ) {
                $label = $button['label-raw'];
            } else {
                $label = htmlspecialchars( $button['value'] );
            }
 
            // @phan-suppress-next-line PhanTypePossiblyInvalidDimOffset Always set in self::addButton
            if ( $button['attribs'] ) {
                // @phan-suppress-next-line PhanTypePossiblyInvalidDimOffset Always set in self::addButton
                $attrs += $button['attribs'];
            }
 
            if ( isset( $button['id'] ) ) {
                $attrs['id'] = $button['id'];
            }
 
            if ( $useMediaWikiUIEverywhere ) {
                $attrs['class'] = isset( $attrs['class'] ) ? (array)$attrs['class'] : [];
                $attrs['class'][] = 'mw-ui-button';
            }
 
            $buttons .= Html::rawElement( 'button', $attrs, $label ) . "\n";
        }
 
        if ( !$buttons ) {
            return '';
        }
 
        return Html::rawElement( 'span',
            [ 'class' => 'mw-htmlform-submit-buttons' ], "\n$buttons" ) . "\n";
    }
 
    public function getBody() {
        return $this->displaySection( $this->mFieldTree, $this->mTableId );
    }
 
    public function getErrorsOrWarnings( $elements, $elementsType ) {
        if ( !in_array( $elementsType, [ 'error', 'warning' ], true ) ) {
            throw new DomainException( $elementsType . ' is not a valid type.' );
        }
        $elementstr = false;
        if ( $elements instanceof Status ) {
            list( $errorStatus, $warningStatus ) = $elements->splitByErrorType();
            $status = $elementsType === 'error' ? $errorStatus : $warningStatus;
            if ( $status->isGood() ) {
                $elementstr = '';
            } else {
                $elementstr = $status
                    ->getMessage()
                    ->setContext( $this )
                    ->setInterfaceMessageFlag( true )
                    ->parse();
            }
        } elseif ( $elementsType === 'error' ) {
            if ( is_array( $elements ) ) {
                $elementstr = $this->formatErrors( $elements );
            } elseif ( $elements && $elements !== true ) {
                $elementstr = (string)$elements;
            }
        }
 
        if ( !$elementstr ) {
            return '';
        } elseif ( $elementsType === 'error' ) {
            return Html::errorBox( $elementstr );
        } else { // $elementsType can only be 'warning'
            return Html::warningBox( $elementstr );
        }
    }
 
    public function formatErrors( $errors ) {
        $errorstr = '';
 
        foreach ( $errors as $error ) {
            $errorstr .= Html::rawElement(
                'li',
                [],
                $this->getMessage( $error )->parse()
            );
        }
 
        $errorstr = Html::rawElement( 'ul', [], $errorstr );
 
        return $errorstr;
    }
 
    public function setSubmitText( $t ) {
        $this->mSubmitText = $t;
 
        return $this;
    }
 
    public function setSubmitDestructive() {
        $this->mSubmitFlags = [ 'destructive', 'primary' ];
 
        return $this;
    }
 
    public function setSubmitTextMsg( $msg ) {
        if ( !$msg instanceof Message ) {
            $msg = $this->msg( $msg );
        }
        $this->setSubmitText( $msg->text() );
 
        return $this;
    }
 
    public function getSubmitText() {
        return $this->mSubmitText ?: $this->msg( 'htmlform-submit' )->text();
    }
 
    public function setSubmitName( $name ) {
        $this->mSubmitName = $name;
 
        return $this;
    }
 
    public function setSubmitTooltip( $name ) {
        $this->mSubmitTooltip = $name;
 
        return $this;
    }
 
    public function setSubmitID( $t ) {
        $this->mSubmitID = $t;
 
        return $this;
    }
 
    public function setFormIdentifier( $ident ) {
        $this->mFormIdentifier = $ident;
 
        return $this;
    }
 
    public function suppressDefaultSubmit( $suppressSubmit = true ) {
        $this->mShowSubmit = !$suppressSubmit;
 
        return $this;
    }
 
    public function showCancel( $show = true ) {
        $this->mShowCancel = $show;
        return $this;
    }
 
    public function setCancelTarget( $target ) {
        if ( $target instanceof PageReference ) {
            $target = TitleValue::castPageToLinkTarget( $target );
        }
 
        $this->mCancelTarget = $target;
        return $this;
    }
 
    protected function getCancelTargetURL() {
        if ( is_string( $this->mCancelTarget ) ) {
            return $this->mCancelTarget;
        } else {
            // TODO: use a service to get the local URL for a LinkTarget, see T282283
            $target = Title::castFromLinkTarget( $this->mCancelTarget ) ?: Title::newMainPage();
            return $target->getLocalURL();
        }
    }
 
    public function setTableId( $id ) {
        $this->mTableId = $id;
 
        return $this;
    }
 
    public function setId( $id ) {
        $this->mId = $id;
 
        return $this;
    }
 
    public function setName( $name ) {
        $this->mName = $name;
 
        return $this;
    }
 
    public function setWrapperLegend( $legend ) {
        $this->mWrapperLegend = $legend;
 
        return $this;
    }
 
    public function setWrapperAttributes( $attributes ) {
        $this->mWrapperAttributes = $attributes;
 
        return $this;
    }
 
    public function setWrapperLegendMsg( $msg ) {
        if ( !$msg instanceof Message ) {
            $msg = $this->msg( $msg );
        }
        $this->setWrapperLegend( $msg->text() );
 
        return $this;
    }
 
    public function setMessagePrefix( $p ) {
        $this->mMessagePrefix = $p;
 
        return $this;
    }
 
    public function setTitle( $t ) {
        // TODO: make mTitle a PageReference when we have a better way to get URLs, see T282283.
        $this->mTitle = Title::castFromPageReference( $t );
 
        return $this;
    }
 
    public function getTitle() {
        return $this->mTitle ?: $this->getContext()->getTitle();
    }
 
    public function setMethod( $method = 'post' ) {
        $this->mMethod = strtolower( $method );
 
        return $this;
    }
 
    public function getMethod() {
        return $this->mMethod;
    }
 
    protected function wrapFieldSetSection( $legend, $section, $attributes, $isRoot ) {
        return Xml::fieldset( $legend, $section, $attributes ) . "\n";
    }
 
    public function displaySection( $fields,
        $sectionName = '',
        $fieldsetIDPrefix = '',
        &$hasUserVisibleFields = false
    ) {
        if ( $this->mFieldData === null ) {
            throw new LogicException( 'HTMLForm::displaySection() called on uninitialized field data. '
                . 'You probably called displayForm() without calling prepareForm() first.' );
        }
 
        $displayFormat = $this->getDisplayFormat();
 
        $html = [];
        $subsectionHtml = '';
        $hasLabel = false;
 
        // Conveniently, PHP method names are case-insensitive.
        // For grep: this can call getDiv, getRaw, getInline, getVForm, getOOUI
        $getFieldHtmlMethod = $displayFormat === 'table' ? 'getTableRow' : ( 'get' . $displayFormat );
 
        foreach ( $fields as $key => $value ) {
            if ( $value instanceof HTMLFormField ) {
                $v = array_key_exists( $key, $this->mFieldData )
                    ? $this->mFieldData[$key]
                    : $value->getDefault();
 
                $retval = $value->$getFieldHtmlMethod( $v );
 
                // check, if the form field should be added to
                // the output.
                if ( $value->hasVisibleOutput() ) {
                    $html[] = $retval;
 
                    $labelValue = trim( $value->getLabel() );
                    if ( $labelValue !== "\u{00A0}" && $labelValue !== '&#160;' && $labelValue !== '' ) {
                        $hasLabel = true;
                    }
 
                    $hasUserVisibleFields = true;
                }
            } elseif ( is_array( $value ) ) {
                $subsectionHasVisibleFields = false;
                $section =
                    $this->displaySection( $value,
                        "mw-htmlform-$key",
                        "$fieldsetIDPrefix$key-",
                        $subsectionHasVisibleFields );
                $legend = null;
 
                if ( $subsectionHasVisibleFields === true ) {
                    // Display the section with various niceties.
                    $hasUserVisibleFields = true;
 
                    $legend = $this->getLegend( $key );
 
                    $section = $this->getHeaderText( $key ) .
                        $section .
                        $this->getFooterText( $key );
 
                    $attributes = [];
                    if ( $fieldsetIDPrefix ) {
                        $attributes['id'] = Sanitizer::escapeIdForAttribute( "$fieldsetIDPrefix$key" );
                    }
                    $subsectionHtml .= $this->wrapFieldSetSection(
                        $legend, $section, $attributes, $fields === $this->mFieldTree
                    );
                } else {
                    // Just return the inputs, nothing fancy.
                    $subsectionHtml .= $section;
                }
            }
        }
 
        $html = $this->formatSection( $html, $sectionName, $hasLabel );
 
        if ( $subsectionHtml ) {
            if ( $this->mSubSectionBeforeFields ) {
                return $subsectionHtml . "\n" . $html;
            } else {
                return $html . "\n" . $subsectionHtml;
            }
        } else {
            return $html;
        }
    }
 
    protected function formatSection( array $fieldsHtml, $sectionName, $anyFieldHasLabel ) {
        if ( !$fieldsHtml ) {
            // Do not generate any wrappers for empty sections. Sections may be empty if they only have
            // subsections, but no fields. A legend will still be added in wrapFieldSetSection().
            return '';
        }
 
        $displayFormat = $this->getDisplayFormat();
        $html = implode( '', $fieldsHtml );
 
        if ( $displayFormat === 'raw' ) {
            return $html;
        }
 
        $classes = [];
 
        if ( !$anyFieldHasLabel ) { // Avoid strange spacing when no labels exist
            $classes[] = 'mw-htmlform-nolabel';
        }
 
        $attribs = [ 'class' => $classes ];
 
        if ( $sectionName ) {
            $attribs['id'] = Sanitizer::escapeIdForAttribute( $sectionName );
        }
 
        if ( $displayFormat === 'table' ) {
            return Html::rawElement( 'table',
                    $attribs,
                    Html::rawElement( 'tbody', [], "\n$html\n" ) ) . "\n";
        } elseif ( $displayFormat === 'inline' ) {
            return Html::rawElement( 'span', $attribs, "\n$html\n" );
        } else {
            return Html::rawElement( 'div', $attribs, "\n$html\n" );
        }
    }
 
    public function loadData() {
        $this->prepareForm();
    }
 
    protected function loadFieldData() {
        $fieldData = [];
        $request = $this->getRequest();
 
        foreach ( $this->mFlatFields as $fieldname => $field ) {
            if ( $field->skipLoadData( $request ) ) {
                continue;
            }
            if ( $field->mParams['disabled'] ?? false ) {
                $fieldData[$fieldname] = $field->getDefault();
            } else {
                $fieldData[$fieldname] = $field->loadDataFromRequest( $request );
            }
        }
 
        // Reset to default for fields that are supposed to be disabled.
        // FIXME: Handle dependency chains, fields that a field checks on may need a reset too.
        foreach ( $fieldData as $name => &$value ) {
            $field = $this->mFlatFields[$name];
            if ( $field->isDisabled( $fieldData ) ) {
                $value = $field->getDefault();
            }
        }
 
        # Filter data.
        foreach ( $fieldData as $name => &$value ) {
            $field = $this->mFlatFields[$name];
            $value = $field->filter( $value, $fieldData );
        }
 
        $this->mFieldData = $fieldData;
    }
 
    public function suppressReset( $suppressReset = true ) {
        $this->mShowReset = !$suppressReset;
 
        return $this;
    }
 
    public function filterDataForSubmit( $data ) {
        return $data;
    }
 
    public function getLegend( $key ) {
        return $this->msg( $this->mMessagePrefix ? "{$this->mMessagePrefix}-$key" : $key )->text();
    }
 
    public function setAction( $action ) {
        $this->mAction = $action;
 
        return $this;
    }
 
    public function getAction() {
        // If an action is already provided, return it
        if ( $this->mAction !== false ) {
            return $this->mAction;
        }
 
        $articlePath = $this->getConfig()->get( MainConfigNames::ArticlePath );
        // Check whether we are in GET mode and the ArticlePath contains a "?"
        // meaning that getLocalURL() would return something like "index.php?title=...".
        // As browser remove the query string before submitting GET forms,
        // it means that the title would be lost. In such case use script path instead
        // and put title in an hidden field (see getHiddenFields()).
        if ( strpos( $articlePath, '?' ) !== false && $this->getMethod() === 'get' ) {
            return $this->getConfig()->get( MainConfigNames::Script );
        }
 
        return $this->getTitle()->getLocalURL();
    }
 
    public function setAutocomplete( $autocomplete ) {
        $this->mAutocomplete = $autocomplete;
 
        return $this;
    }
 
    protected function getMessage( $value ) {
        return Message::newFromSpecifier( $value )->setContext( $this );
    }
 
    public function needsJSForHtml5FormValidation() {
        foreach ( $this->mFlatFields as $fieldname => $field ) {
            if ( $field->needsJSForHtml5FormValidation() ) {
                return true;
            }
        }
        return false;
    }
}