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Diffstat (limited to 'src/gui/text/qtextmarkdownimporter.cpp')
| -rw-r--r-- | src/gui/text/qtextmarkdownimporter.cpp | 568 |
1 files changed, 568 insertions, 0 deletions
diff --git a/src/gui/text/qtextmarkdownimporter.cpp b/src/gui/text/qtextmarkdownimporter.cpp new file mode 100644 index 0000000000..fe7e422923 --- /dev/null +++ b/src/gui/text/qtextmarkdownimporter.cpp @@ -0,0 +1,568 @@ +/**************************************************************************** +** +** Copyright (C) 2019 The Qt Company Ltd. +** Contact: https://www.qt.io/licensing/ +** +** This file is part of the QtGui module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** Commercial License Usage +** Licensees holding valid commercial Qt licenses may use this file in +** accordance with the commercial license agreement provided with the +** Software or, alternatively, in accordance with the terms contained in +** a written agreement between you and The Qt Company. For licensing terms +** and conditions see https://www.qt.io/terms-conditions. For further +** information use the contact form at https://www.qt.io/contact-us. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 3 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL3 included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 3 requirements +** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 2.0 or (at your option) the GNU General +** Public license version 3 or any later version approved by the KDE Free +** Qt Foundation. The licenses are as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 +** included in the packaging of this file. Please review the following +** information to ensure the GNU General Public License requirements will +** be met: https://www.gnu.org/licenses/gpl-2.0.html and +** https://www.gnu.org/licenses/gpl-3.0.html. +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qtextmarkdownimporter_p.h" +#include "qtextdocumentfragment_p.h" +#include <QLoggingCategory> +#if QT_CONFIG(regularexpression) +#include <QRegularExpression> +#endif +#include <QTextCursor> +#include <QTextDocument> +#include <QTextDocumentFragment> +#include <QTextList> +#include <QTextTable> +#include "../../3rdparty/md4c/md4c.h" + +QT_BEGIN_NAMESPACE + +Q_LOGGING_CATEGORY(lcMD, "qt.text.markdown") + +static const QChar Newline = QLatin1Char('\n'); +static const QChar Space = QLatin1Char(' '); + +// TODO maybe eliminate the margins after all views recognize BlockQuoteLevel, CSS can format it, etc. +static const int BlockQuoteIndent = 40; // pixels, same as in QTextHtmlParserNode::initializeProperties + +// -------------------------------------------------------- +// MD4C callback function wrappers + +static int CbEnterBlock(MD_BLOCKTYPE type, void *detail, void *userdata) +{ + QTextMarkdownImporter *mdi = static_cast<QTextMarkdownImporter *>(userdata); + return mdi->cbEnterBlock(int(type), detail); +} + +static int CbLeaveBlock(MD_BLOCKTYPE type, void *detail, void *userdata) +{ + QTextMarkdownImporter *mdi = static_cast<QTextMarkdownImporter *>(userdata); + return mdi->cbLeaveBlock(int(type), detail); +} + +static int CbEnterSpan(MD_SPANTYPE type, void *detail, void *userdata) +{ + QTextMarkdownImporter *mdi = static_cast<QTextMarkdownImporter *>(userdata); + return mdi->cbEnterSpan(int(type), detail); +} + +static int CbLeaveSpan(MD_SPANTYPE type, void *detail, void *userdata) +{ + QTextMarkdownImporter *mdi = static_cast<QTextMarkdownImporter *>(userdata); + return mdi->cbLeaveSpan(int(type), detail); +} + +static int CbText(MD_TEXTTYPE type, const MD_CHAR *text, MD_SIZE size, void *userdata) +{ + QTextMarkdownImporter *mdi = static_cast<QTextMarkdownImporter *>(userdata); + return mdi->cbText(int(type), text, size); +} + +static void CbDebugLog(const char *msg, void *userdata) +{ + Q_UNUSED(userdata) + qCDebug(lcMD) << msg; +} + +// MD4C callback function wrappers +// -------------------------------------------------------- + +static Qt::Alignment MdAlignment(MD_ALIGN a, Qt::Alignment defaultAlignment = Qt::AlignLeft | Qt::AlignVCenter) +{ + switch (a) { + case MD_ALIGN_LEFT: + return Qt::AlignLeft | Qt::AlignVCenter; + case MD_ALIGN_CENTER: + return Qt::AlignHCenter | Qt::AlignVCenter; + case MD_ALIGN_RIGHT: + return Qt::AlignRight | Qt::AlignVCenter; + default: // including MD_ALIGN_DEFAULT + return defaultAlignment; + } +} + +QTextMarkdownImporter::QTextMarkdownImporter(QTextMarkdownImporter::Features features) + : m_monoFont(QFontDatabase::systemFont(QFontDatabase::FixedFont)) + , m_features(features) +{ +} + +void QTextMarkdownImporter::import(QTextDocument *doc, const QString &markdown) +{ + MD_PARSER callbacks = { + 0, // abi_version + unsigned(m_features), + &CbEnterBlock, + &CbLeaveBlock, + &CbEnterSpan, + &CbLeaveSpan, + &CbText, + &CbDebugLog, + nullptr // syntax + }; + m_doc = doc; + m_paragraphMargin = m_doc->defaultFont().pointSize() * 2 / 3; + m_cursor = new QTextCursor(doc); + doc->clear(); + qCDebug(lcMD) << "default font" << doc->defaultFont() << "mono font" << m_monoFont; + QByteArray md = markdown.toUtf8(); + md_parse(md.constData(), MD_SIZE(md.size()), &callbacks, this); + delete m_cursor; + m_cursor = nullptr; +} + +int QTextMarkdownImporter::cbEnterBlock(int blockType, void *det) +{ + m_blockType = blockType; + switch (blockType) { + case MD_BLOCK_P: + if (!m_listStack.isEmpty()) + qCDebug(lcMD, m_listItem ? "P of LI at level %d" : "P continuation inside LI at level %d", m_listStack.count()); + else + qCDebug(lcMD, "P"); + m_needsInsertBlock = true; + break; + case MD_BLOCK_QUOTE: + ++m_blockQuoteDepth; + qCDebug(lcMD, "QUOTE level %d", m_blockQuoteDepth); + break; + case MD_BLOCK_CODE: { + MD_BLOCK_CODE_DETAIL *detail = static_cast<MD_BLOCK_CODE_DETAIL *>(det); + m_codeBlock = true; + m_blockCodeLanguage = QLatin1String(detail->lang.text, int(detail->lang.size)); + m_blockCodeFence = detail->fence_char; + QString info = QLatin1String(detail->info.text, int(detail->info.size)); + m_needsInsertBlock = true; + if (m_blockQuoteDepth) + qCDebug(lcMD, "CODE lang '%s' info '%s' fenced with '%c' inside QUOTE %d", qPrintable(m_blockCodeLanguage), qPrintable(info), m_blockCodeFence, m_blockQuoteDepth); + else + qCDebug(lcMD, "CODE lang '%s' info '%s' fenced with '%c'", qPrintable(m_blockCodeLanguage), qPrintable(info), m_blockCodeFence); + } break; + case MD_BLOCK_H: { + MD_BLOCK_H_DETAIL *detail = static_cast<MD_BLOCK_H_DETAIL *>(det); + QTextBlockFormat blockFmt; + QTextCharFormat charFmt; + int sizeAdjustment = 4 - int(detail->level); // H1 to H6: +3 to -2 + charFmt.setProperty(QTextFormat::FontSizeAdjustment, sizeAdjustment); + charFmt.setFontWeight(QFont::Bold); + blockFmt.setHeadingLevel(int(detail->level)); + m_needsInsertBlock = false; + m_cursor->insertBlock(blockFmt, charFmt); + qCDebug(lcMD, "H%d", detail->level); + } break; + case MD_BLOCK_LI: { + m_needsInsertBlock = true; + m_listItem = true; + MD_BLOCK_LI_DETAIL *detail = static_cast<MD_BLOCK_LI_DETAIL *>(det); + m_markerType = detail->is_task ? + (detail->task_mark == ' ' ? QTextBlockFormat::MarkerType::Unchecked : QTextBlockFormat::MarkerType::Checked) : + QTextBlockFormat::MarkerType::NoMarker; + qCDebug(lcMD) << "LI"; + } break; + case MD_BLOCK_UL: { + MD_BLOCK_UL_DETAIL *detail = static_cast<MD_BLOCK_UL_DETAIL *>(det); + m_listFormat = QTextListFormat(); + m_listFormat.setIndent(m_listStack.count() + 1); + switch (detail->mark) { + case '*': + m_listFormat.setStyle(QTextListFormat::ListCircle); + break; + case '+': + m_listFormat.setStyle(QTextListFormat::ListSquare); + break; + default: // including '-' + m_listFormat.setStyle(QTextListFormat::ListDisc); + break; + } + qCDebug(lcMD, "UL %c level %d", detail->mark, m_listStack.count()); + m_needsInsertList = true; + } break; + case MD_BLOCK_OL: { + MD_BLOCK_OL_DETAIL *detail = static_cast<MD_BLOCK_OL_DETAIL *>(det); + m_listFormat = QTextListFormat(); + m_listFormat.setIndent(m_listStack.count() + 1); + m_listFormat.setNumberSuffix(QChar::fromLatin1(detail->mark_delimiter)); + m_listFormat.setStyle(QTextListFormat::ListDecimal); + qCDebug(lcMD, "OL xx%d level %d", detail->mark_delimiter, m_listStack.count()); + m_needsInsertList = true; + } break; + case MD_BLOCK_TD: { + MD_BLOCK_TD_DETAIL *detail = static_cast<MD_BLOCK_TD_DETAIL *>(det); + ++m_tableCol; + // absolute movement (and storage of m_tableCol) shouldn't be necessary, but + // movePosition(QTextCursor::NextCell) doesn't work + QTextTableCell cell = m_currentTable->cellAt(m_tableRowCount - 1, m_tableCol); + if (!cell.isValid()) { + qWarning("malformed table in Markdown input"); + return 1; + } + *m_cursor = cell.firstCursorPosition(); + QTextBlockFormat blockFmt = m_cursor->blockFormat(); + blockFmt.setAlignment(MdAlignment(detail->align)); + m_cursor->setBlockFormat(blockFmt); + qCDebug(lcMD) << "TD; align" << detail->align << MdAlignment(detail->align) << "col" << m_tableCol; + } break; + case MD_BLOCK_TH: { + ++m_tableColumnCount; + ++m_tableCol; + if (m_currentTable->columns() < m_tableColumnCount) + m_currentTable->appendColumns(1); + auto cell = m_currentTable->cellAt(m_tableRowCount - 1, m_tableCol); + if (!cell.isValid()) { + qWarning("malformed table in Markdown input"); + return 1; + } + auto fmt = cell.format(); + fmt.setFontWeight(QFont::Bold); + cell.setFormat(fmt); + } break; + case MD_BLOCK_TR: { + ++m_tableRowCount; + m_nonEmptyTableCells.clear(); + if (m_currentTable->rows() < m_tableRowCount) + m_currentTable->appendRows(1); + m_tableCol = -1; + qCDebug(lcMD) << "TR" << m_currentTable->rows(); + } break; + case MD_BLOCK_TABLE: + m_tableColumnCount = 0; + m_tableRowCount = 0; + m_currentTable = m_cursor->insertTable(1, 1); // we don't know the dimensions yet + break; + case MD_BLOCK_HR: { + qCDebug(lcMD, "HR"); + QTextBlockFormat blockFmt; + blockFmt.setProperty(QTextFormat::BlockTrailingHorizontalRulerWidth, 1); + m_cursor->insertBlock(blockFmt, QTextCharFormat()); + } break; + default: + break; // nothing to do for now + } + return 0; // no error +} + +int QTextMarkdownImporter::cbLeaveBlock(int blockType, void *detail) +{ + Q_UNUSED(detail) + switch (blockType) { + case MD_BLOCK_P: + m_listItem = false; + break; + case MD_BLOCK_UL: + case MD_BLOCK_OL: + qCDebug(lcMD, "list at level %d ended", m_listStack.count()); + m_listStack.pop(); + break; + case MD_BLOCK_TR: { + // https://github.com/mity/md4c/issues/29 + // MD4C doesn't tell us explicitly which cells are merged, so merge empty cells + // with previous non-empty ones + int mergeEnd = -1; + int mergeBegin = -1; + for (int col = m_tableCol; col >= 0; --col) { + if (m_nonEmptyTableCells.contains(col)) { + if (mergeEnd >= 0 && mergeBegin >= 0) { + qCDebug(lcMD) << "merging cells" << mergeBegin << "to" << mergeEnd << "inclusive, on row" << m_currentTable->rows() - 1; + m_currentTable->mergeCells(m_currentTable->rows() - 1, mergeBegin - 1, 1, mergeEnd - mergeBegin + 2); + } + mergeEnd = -1; + mergeBegin = -1; + } else { + if (mergeEnd < 0) + mergeEnd = col; + else + mergeBegin = col; + } + } + } break; + case MD_BLOCK_QUOTE: { + qCDebug(lcMD, "QUOTE level %d ended", m_blockQuoteDepth); + --m_blockQuoteDepth; + m_needsInsertBlock = true; + } break; + case MD_BLOCK_TABLE: + qCDebug(lcMD) << "table ended with" << m_currentTable->columns() << "cols and" << m_currentTable->rows() << "rows"; + m_currentTable = nullptr; + m_cursor->movePosition(QTextCursor::End); + break; + case MD_BLOCK_LI: + qCDebug(lcMD, "LI at level %d ended", m_listStack.count()); + m_listItem = false; + break; + case MD_BLOCK_CODE: { + m_codeBlock = false; + m_blockCodeLanguage.clear(); + m_blockCodeFence = 0; + if (m_blockQuoteDepth) + qCDebug(lcMD, "CODE ended inside QUOTE %d", m_blockQuoteDepth); + else + qCDebug(lcMD, "CODE ended"); + m_needsInsertBlock = true; + } break; + case MD_BLOCK_H: + m_cursor->setCharFormat(QTextCharFormat()); + break; + default: + break; + } + return 0; // no error +} + +int QTextMarkdownImporter::cbEnterSpan(int spanType, void *det) +{ + QTextCharFormat charFmt; + switch (spanType) { + case MD_SPAN_EM: + charFmt.setFontItalic(true); + break; + case MD_SPAN_STRONG: + charFmt.setFontWeight(QFont::Bold); + break; + case MD_SPAN_A: { + MD_SPAN_A_DETAIL *detail = static_cast<MD_SPAN_A_DETAIL *>(det); + QString url = QString::fromLatin1(detail->href.text, int(detail->href.size)); + QString title = QString::fromLatin1(detail->title.text, int(detail->title.size)); + charFmt.setAnchorHref(url); + charFmt.setAnchorNames(QStringList(title)); + charFmt.setForeground(m_palette.link()); + qCDebug(lcMD) << "anchor" << url << title; + } break; + case MD_SPAN_IMG: { + m_imageSpan = true; + m_imageFormat = QTextImageFormat(); + MD_SPAN_IMG_DETAIL *detail = static_cast<MD_SPAN_IMG_DETAIL *>(det); + m_imageFormat.setName(QString::fromUtf8(detail->src.text, int(detail->src.size))); + m_imageFormat.setProperty(QTextFormat::ImageTitle, QString::fromUtf8(detail->title.text, int(detail->title.size))); + break; + } + case MD_SPAN_CODE: + charFmt.setFont(m_monoFont); + break; + case MD_SPAN_DEL: + charFmt.setFontStrikeOut(true); + break; + } + m_spanFormatStack.push(charFmt); + qCDebug(lcMD) << spanType << "setCharFormat" << charFmt.font().family() << charFmt.fontWeight() + << (charFmt.fontItalic() ? "italic" : "") << charFmt.foreground().color().name(); + m_cursor->setCharFormat(charFmt); + return 0; // no error +} + +int QTextMarkdownImporter::cbLeaveSpan(int spanType, void *detail) +{ + Q_UNUSED(detail) + QTextCharFormat charFmt; + if (!m_spanFormatStack.isEmpty()) { + m_spanFormatStack.pop(); + if (!m_spanFormatStack.isEmpty()) + charFmt = m_spanFormatStack.top(); + } + m_cursor->setCharFormat(charFmt); + qCDebug(lcMD) << spanType << "setCharFormat" << charFmt.font().family() << charFmt.fontWeight() + << (charFmt.fontItalic() ? "italic" : "") << charFmt.foreground().color().name(); + if (spanType == int(MD_SPAN_IMG)) + m_imageSpan = false; + return 0; // no error +} + +int QTextMarkdownImporter::cbText(int textType, const char *text, unsigned size) +{ + if (m_needsInsertBlock) + insertBlock(); +#if QT_CONFIG(regularexpression) + static const QRegularExpression openingBracket(QStringLiteral("<[a-zA-Z]")); + static const QRegularExpression closingBracket(QStringLiteral("(/>|</)")); +#endif + QString s = QString::fromUtf8(text, int(size)); + + switch (textType) { + case MD_TEXT_NORMAL: +#if QT_CONFIG(regularexpression) + if (m_htmlTagDepth) { + m_htmlAccumulator += s; + s = QString(); + } +#endif + break; + case MD_TEXT_NULLCHAR: + s = QString(QChar(0xFFFD)); // CommonMark-required replacement for null + break; + case MD_TEXT_BR: + s = QString(Newline); + break; + case MD_TEXT_SOFTBR: + s = QString(Space); + break; + case MD_TEXT_CODE: + // We'll see MD_SPAN_CODE too, which will set the char format, and that's enough. + break; +#if QT_CONFIG(texthtmlparser) + case MD_TEXT_ENTITY: + m_cursor->insertHtml(s); + s = QString(); + break; +#endif + case MD_TEXT_HTML: + // count how many tags are opened and how many are closed +#if QT_CONFIG(regularexpression) && QT_CONFIG(texthtmlparser) + { + int startIdx = 0; + while ((startIdx = s.indexOf(openingBracket, startIdx)) >= 0) { + ++m_htmlTagDepth; + startIdx += 2; + } + startIdx = 0; + while ((startIdx = s.indexOf(closingBracket, startIdx)) >= 0) { + --m_htmlTagDepth; + startIdx += 2; + } + } + m_htmlAccumulator += s; + if (!m_htmlTagDepth) { // all open tags are now closed + qCDebug(lcMD) << "HTML" << m_htmlAccumulator; + m_cursor->insertHtml(m_htmlAccumulator); + if (m_spanFormatStack.isEmpty()) + m_cursor->setCharFormat(QTextCharFormat()); + else + m_cursor->setCharFormat(m_spanFormatStack.top()); + m_htmlAccumulator = QString(); + } +#endif + s = QString(); + break; + } + + switch (m_blockType) { + case MD_BLOCK_TD: + m_nonEmptyTableCells.append(m_tableCol); + break; + default: + break; + } + + if (m_imageSpan) { + // TODO we don't yet support alt text with formatting, because of the cases where m_cursor + // already inserted the text above. Rather need to accumulate it in case we need it here. + m_imageFormat.setProperty(QTextFormat::ImageAltText, s); + qCDebug(lcMD) << "image" << m_imageFormat.name() + << "title" << m_imageFormat.stringProperty(QTextFormat::ImageTitle) + << "alt" << s << "relative to" << m_doc->baseUrl(); + m_cursor->insertImage(m_imageFormat); + return 0; // no error + } + + if (!s.isEmpty()) + m_cursor->insertText(s); + if (m_cursor->currentList()) { + // The list item will indent the list item's text, so we don't need indentation on the block. + QTextBlockFormat bfmt = m_cursor->blockFormat(); + bfmt.setIndent(0); + m_cursor->setBlockFormat(bfmt); + } + if (lcMD().isEnabled(QtDebugMsg)) { + QTextBlockFormat bfmt = m_cursor->blockFormat(); + QString debugInfo; + if (m_cursor->currentList()) + debugInfo = QLatin1String("in list at depth ") + QString::number(m_cursor->currentList()->format().indent()); + if (bfmt.hasProperty(QTextFormat::BlockQuoteLevel)) + debugInfo += QLatin1String("in blockquote at depth ") + + QString::number(bfmt.intProperty(QTextFormat::BlockQuoteLevel)); + if (bfmt.hasProperty(QTextFormat::BlockCodeLanguage)) + debugInfo += QLatin1String("in a code block"); + qCDebug(lcMD) << textType << "in block" << m_blockType << s << qPrintable(debugInfo) + << "bindent" << bfmt.indent() << "tindent" << bfmt.textIndent() + << "margins" << bfmt.leftMargin() << bfmt.topMargin() << bfmt.bottomMargin() << bfmt.rightMargin(); + } + qCDebug(lcMD) << textType << "in block" << m_blockType << s << "in list?" << m_cursor->currentList() + << "indent" << m_cursor->blockFormat().indent(); + return 0; // no error +} + +/*! + Insert a new block based on stored state. + + m_cursor cannot store the state for the _next_ block ahead of time, because + m_cursor->setBlockFormat() controls the format of the block that the cursor + is already in; so cbLeaveBlock() cannot call setBlockFormat() without + altering the block that was just added. Therefore cbLeaveBlock() and the + following cbEnterBlock() set variables to remember what formatting should + come next, and insertBlock() is called just before the actual text + insertion, to create a new block with the right formatting. +*/ +void QTextMarkdownImporter::insertBlock() +{ + QTextCharFormat charFormat; + if (!m_spanFormatStack.isEmpty()) + charFormat = m_spanFormatStack.top(); + QTextBlockFormat blockFormat; + if (!m_listStack.isEmpty() && !m_needsInsertList && m_listItem) { + QTextList *list = m_listStack.top(); + blockFormat = list->item(list->count() - 1).blockFormat(); + } + if (m_blockQuoteDepth) { + blockFormat.setProperty(QTextFormat::BlockQuoteLevel, m_blockQuoteDepth); + blockFormat.setLeftMargin(BlockQuoteIndent * m_blockQuoteDepth); + blockFormat.setRightMargin(BlockQuoteIndent); + } + if (m_codeBlock) { + blockFormat.setProperty(QTextFormat::BlockCodeLanguage, m_blockCodeLanguage); + if (m_blockCodeFence) + blockFormat.setProperty(QTextFormat::BlockCodeFence, QString(QLatin1Char(m_blockCodeFence))); + charFormat.setFont(m_monoFont); + } else { + blockFormat.setTopMargin(m_paragraphMargin); + blockFormat.setBottomMargin(m_paragraphMargin); + } + if (m_markerType == QTextBlockFormat::MarkerType::NoMarker) + blockFormat.clearProperty(QTextFormat::BlockMarker); + else + blockFormat.setMarker(m_markerType); + if (!m_listStack.isEmpty()) + blockFormat.setIndent(m_listStack.count()); + m_cursor->insertBlock(blockFormat, charFormat); + if (m_needsInsertList) { + m_listStack.push(m_cursor->createList(m_listFormat)); + } else if (!m_listStack.isEmpty() && m_listItem) { + m_listStack.top()->add(m_cursor->block()); + } + m_needsInsertList = false; + m_needsInsertBlock = false; +} + +QT_END_NAMESPACE |