protected function html2ooNodeInt($srcNode, $lineNumbered, $inP, $parentStyles = [])
    {
        switch ($srcNode->nodeType) {
            case XML_ELEMENT_NODE:
                /** @var \DOMElement $srcNode */
                if ($this->DEBUG) {
                    echo "Element - " . $srcNode->nodeName . " / Children: " . $srcNode->childNodes->length . "<br>";
                }
                $needsIntermediateP = false;
                $childStyles        = static::getChildStyles($srcNode, $parentStyles);
                switch ($srcNode->nodeName) {
                    case 'b':
                    case 'strong':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenBold');
                        break;
                    case 'i':
                    case 'em':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenItalic');
                        break;
                    case 's':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenStrike');
                        break;
                    case 'u':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenUnderlined');
                        break;
                    case 'sub':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenSub');
                        break;
                    case 'sup':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenSup');
                        break;
                    case 'br':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'line-break');
                        break;
                    case 'del':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenDel');
                        break;
                    case 'ins':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenIns');
                        break;
                    case 'a':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'a');
                        try {
                            $attr = $srcNode->getAttribute('href');
                            if ($attr) {
                                $dstEl->setAttribute('xlink:href', $attr);
                            }
                        } catch (\Exception $e) {
                        }
                        break;
                    case 'p':
                        if ($inP) {
                            $dstEl = $this->createNodeWithBaseStyle('span', $lineNumbered);
                        } else {
                            $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        }
                        $intClass = static::cssClassesToInternalClass(static::getCSSClasses($srcNode));
                        if ($intClass) {
                            $dstEl->setAttribute('text:style-name', $intClass);
                        }
                        $inP = true;
                        break;
                    case 'div':
                        // We're basically ignoring DIVs here, as there is no corresponding element in OpenDocument
                        // Therefore no support for styles and classes set on DIVs yet.
                        $dstEl = null;
                        break;
                    case 'blockquote':
                        $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        $class = ($lineNumbered ? 'Blockquote_Linenumbered' : 'Blockquote');
                        $dstEl->setAttribute('text:style-name', 'Antragsgrün_20_' . $class);
                        if ($srcNode->childNodes->length == 1) {
                            foreach ($srcNode->childNodes as $child) {
                                if ($child->nodeName == 'p') {
                                    $srcNode = $child;
                                }
                            }
                        }
                        $inP = true;
                        break;
                    case 'ul':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'list');
                        break;
                    case 'ol':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'list');
                        break;
                    case 'li':
                        $dstEl              = $this->doc->createElementNS(static::NS_TEXT, 'list-item');
                        $needsIntermediateP = true;
                        $inP                = true;
                        break;
                    case 'h1':
                        $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        $dstEl->setAttribute('text:style-name', 'Antragsgrün_20_H1');
                        $inP = true;
                        break;
                    case 'h2':
                        $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        $dstEl->setAttribute('text:style-name', 'Antragsgrün_20_H2');
                        $inP = true;
                        break;
                    case 'h3':
                        $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        $dstEl->setAttribute('text:style-name', 'Antragsgrün_20_H3');
                        $inP = true;
                        break;
                    case 'h4':
                    case 'h5':
                    case 'h6':
                        $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        $dstEl->setAttribute('text:style-name', 'Antragsgrün_20_H4');
                        $inP = true;
                        break;
                    case 'span':
                    default:
                        $dstEl    = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $intClass = static::cssClassesToInternalClass(static::getCSSClasses($srcNode));
                        if ($intClass) {
                            $dstEl->setAttribute('text:style-name', $intClass);
                        }
                        break;
                }


                if ($dstEl === null) {
                    $ret = [];
                    foreach ($srcNode->childNodes as $child) {
                        /** @var \DOMNode $child */
                        if ($this->DEBUG) {
                            echo "CHILD<br>" . $child->nodeType . "<br>";
                        }

                        $dstNodes = $this->html2ooNodeInt($child, $lineNumbered, $inP, $childStyles);
                        foreach ($dstNodes as $dstNode) {
                            $ret[] = $dstNode;
                        }
                    }
                    return $ret;
                }

                foreach ($srcNode->childNodes as $child) {
                    /** @var \DOMNode $child */
                    if ($this->DEBUG) {
                        echo "CHILD<br>" . $child->nodeType . "<br>";
                    }

                    $dstNodes = $this->html2ooNodeInt($child, $lineNumbered, $inP, $childStyles);
                    foreach ($dstNodes as $dstNode) {
                        $dstEl->appendChild($dstNode);
                    }
                }

                if ($needsIntermediateP && $dstEl->childNodes->length > 0) {
                    $dstEl = static::wrapChildrenWithP($dstEl, $lineNumbered);
                }
                return [$dstEl];
            case XML_TEXT_NODE:
                /** @var \DOMText $srcNode */
                $textnode       = new \DOMText();
                $textnode->data = $srcNode->data;
                if ($this->DEBUG) {
                    echo 'Text<br>';
                }
                if (in_array(static::STYLE_DEL, $parentStyles)) {
                    $dstEl = $this->createNodeWithBaseStyle('span', $lineNumbered);
                    $dstEl->setAttribute('text:style-name', 'AntragsgruenDel');
                    $dstEl->appendChild($textnode);
                    $textnode = $dstEl;
                }
                if (in_array(static::STYLE_INS, $parentStyles)) {
                    $dstEl = $this->createNodeWithBaseStyle('span', $lineNumbered);
                    $dstEl->setAttribute('text:style-name', 'AntragsgruenIns');
                    $dstEl->appendChild($textnode);
                    $textnode = $dstEl;
                }
                return [$textnode];
                break;
            case XML_DOCUMENT_TYPE_NODE:
                if ($this->DEBUG) {
                    echo 'Type Node<br>';
                }
                return [];
            default:
                if ($this->DEBUG) {
                    echo 'Unknown Node: ' . $srcNode->nodeType . '<br>';
                }
                return [];
        }
    }
protected function html2ooNodeInt($srcNode, $lineNumbered, $inP, $parentStyles = [])
    {
        switch ($srcNode->nodeType) {
            case XML_ELEMENT_NODE:
                /** @var \DOMElement $srcNode */
                if ($this->DEBUG) {
                    echo "Element - " . $srcNode->nodeName . " / Children: " . $srcNode->childNodes->length . "<br>";
                }
                $needsIntermediateP = false;
                $childStyles        = static::getChildStyles($srcNode, $parentStyles);
                switch ($srcNode->nodeName) {
                    case 'b':
                    case 'strong':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenBold');
                        break;
                    case 'i':
                    case 'em':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenItalic');
                        break;
                    case 's':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenStrike');
                        break;
                    case 'u':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenUnderlined');
                        break;
                    case 'sub':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenSub');
                        break;
                    case 'sup':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenSup');
                        break;
                    case 'br':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'line-break');
                        break;
                    case 'del':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenDel');
                        break;
                    case 'ins':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $dstEl->setAttribute('text:style-name', 'AntragsgruenIns');
                        break;
                    case 'a':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'a');
                        try {
                            $attr = $srcNode->getAttribute('href');
                            if ($attr) {
                                $dstEl->setAttribute('xlink:href', $attr);
                            }
                        } catch (\Exception $e) {
                        }
                        break;
                    case 'p':
                        if ($inP) {
                            $dstEl = $this->createNodeWithBaseStyle('span', $lineNumbered);
                        } else {
                            $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        }
                        $intClass = static::cssClassesToInternalClass(static::getCSSClasses($srcNode));
                        if ($intClass) {
                            $dstEl->setAttribute('text:style-name', $intClass);
                        }
                        $inP = true;
                        break;
                    case 'div':
                        // We're basically ignoring DIVs here, as there is no corresponding element in OpenDocument
                        // Therefore no support for styles and classes set on DIVs yet.
                        $dstEl = null;
                        break;
                    case 'blockquote':
                        $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        $class = ($lineNumbered ? 'Blockquote_Linenumbered' : 'Blockquote');
                        $dstEl->setAttribute('text:style-name', 'Antragsgrün_20_' . $class);
                        if ($srcNode->childNodes->length == 1) {
                            foreach ($srcNode->childNodes as $child) {
                                if ($child->nodeName == 'p') {
                                    $srcNode = $child;
                                }
                            }
                        }
                        $inP = true;
                        break;
                    case 'ul':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'list');
                        break;
                    case 'ol':
                        $dstEl = $this->doc->createElementNS(static::NS_TEXT, 'list');
                        break;
                    case 'li':
                        $dstEl              = $this->doc->createElementNS(static::NS_TEXT, 'list-item');
                        $needsIntermediateP = true;
                        $inP                = true;
                        break;
                    case 'h1':
                        $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        $dstEl->setAttribute('text:style-name', 'Antragsgrün_20_H1');
                        $inP = true;
                        break;
                    case 'h2':
                        $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        $dstEl->setAttribute('text:style-name', 'Antragsgrün_20_H2');
                        $inP = true;
                        break;
                    case 'h3':
                        $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        $dstEl->setAttribute('text:style-name', 'Antragsgrün_20_H3');
                        $inP = true;
                        break;
                    case 'h4':
                    case 'h5':
                    case 'h6':
                        $dstEl = $this->createNodeWithBaseStyle('p', $lineNumbered);
                        $dstEl->setAttribute('text:style-name', 'Antragsgrün_20_H4');
                        $inP = true;
                        break;
                    case 'span':
                    default:
                        $dstEl    = $this->doc->createElementNS(static::NS_TEXT, 'span');
                        $intClass = static::cssClassesToInternalClass(static::getCSSClasses($srcNode));
                        if ($intClass) {
                            $dstEl->setAttribute('text:style-name', $intClass);
                        }
                        break;
                }


                if ($dstEl === null) {
                    $ret = [];
                    foreach ($srcNode->childNodes as $child) {
                        /** @var \DOMNode $child */
                        if ($this->DEBUG) {
                            echo "CHILD<br>" . $child->nodeType . "<br>";
                        }

                        $dstNodes = $this->html2ooNodeInt($child, $lineNumbered, $inP, $childStyles);
                        foreach ($dstNodes as $dstNode) {
                            $ret[] = $dstNode;
                        }
                    }
                    return $ret;
                }

                foreach ($srcNode->childNodes as $child) {
                    /** @var \DOMNode $child */
                    if ($this->DEBUG) {
                        echo "CHILD<br>" . $child->nodeType . "<br>";
                    }

                    $dstNodes = $this->html2ooNodeInt($child, $lineNumbered, $inP, $childStyles);
                    foreach ($dstNodes as $dstNode) {
                        $dstEl->appendChild($dstNode);
                    }
                }

                if ($needsIntermediateP && $dstEl->childNodes->length > 0) {
                    $dstEl = static::wrapChildrenWithP($dstEl, $lineNumbered);
                }
                return [$dstEl];
            case XML_TEXT_NODE:
                /** @var \DOMText $srcNode */
                $textnode       = new \DOMText();
                $textnode->data = $srcNode->data;
                if ($this->DEBUG) {
                    echo 'Text<br>';
                }
                if (in_array(static::STYLE_DEL, $parentStyles)) {
                    $dstEl = $this->createNodeWithBaseStyle('span', $lineNumbered);
                    $dstEl->setAttribute('text:style-name', 'AntragsgruenDel');
                    $dstEl->appendChild($textnode);
                    $textnode = $dstEl;
                }
                if (in_array(static::STYLE_INS, $parentStyles)) {
                    $dstEl = $this->createNodeWithBaseStyle('span', $lineNumbered);
                    $dstEl->setAttribute('text:style-name', 'AntragsgruenIns');
                    $dstEl->appendChild($textnode);
                    $textnode = $dstEl;
                }
                return [$textnode];
                break;
            case XML_DOCUMENT_TYPE_NODE:
                if ($this->DEBUG) {
                    echo 'Type Node<br>';
                }
                return [];
            default:
                if ($this->DEBUG) {
                    echo 'Unknown Node: ' . $srcNode->nodeType . '<br>';
                }
                return [];
        }
    }
@param \DOMNode $srcNode
@param bool $lineNumbered
@param bool $inP
@param string[]   $parentStyles

@return \DOMNode[]
@throws \Exception