initial upload

2023-11-15 20:54:49 +01:00
parent b90a34c4b4
commit 99dad98ce0
29 changed files with 1277 additions and 0 deletions
--- a/src/richtexteditor.cpp
+++ b/src/richtexteditor.cpp
@@ -0,0 +1,179 @@
+#include "richtexteditor.h"
+#include "richtexteditortoolbar.h"
+
+#include <QXmlStreamReader>
+#include <QXmlStreamWriter>
+#include <QStringView>
+#include <QStringLiteral>
+
+#include <algorithm>
+
+const bool simplifyRichTextDefault = true;
+
+using namespace Qt::StringLiterals;
+
+// Richtext simplification filter helpers: Elements to be discarded
+static inline bool filterElement(QStringView name)
+{
+    return name != "meta"_L1 && name != "style"_L1;
+}
+
+// Richtext simplification filter helpers: Filter attributes of elements
+static inline void filterAttributes(QStringView name,
+                                    QXmlStreamAttributes *atts,
+                                    bool *paragraphAlignmentFound)
+{
+    if (atts->isEmpty())
+        return;
+
+    // No style attributes for <body>
+    if (name == "body"_L1) {
+        atts->clear();
+        return;
+    }
+
+    // Clean out everything except 'align' for 'p'
+    if (name == "p"_L1) {
+        for (auto it = atts->begin(); it != atts->end(); ) {
+            if (it->name() == "align"_L1) {
+                ++it;
+                *paragraphAlignmentFound = true;
+            } else {
+                it = atts->erase(it);
+            }
+        }
+        return;
+    }
+}
+
+// Richtext simplification filter helpers: Check for blank QStringView.
+static inline bool isWhiteSpace(QStringView in)
+{
+    return std::all_of(in.cbegin(), in.cend(),
+                       [](QChar c) { return c.isSpace(); });
+}
+
+// Richtext simplification filter: Remove hard-coded font settings,
+// <style> elements, <p> attributes other than 'align' and
+// and unnecessary meta-information.
+QString simplifyRichTextFilter(const QString &in, bool *isPlainTextPtr = nullptr)
+{
+    unsigned elementCount = 0;
+    bool paragraphAlignmentFound = false;
+    QString out;
+    QXmlStreamReader reader(in);
+    QXmlStreamWriter writer(&out);
+    writer.setAutoFormatting(false);
+    writer.setAutoFormattingIndent(0);
+
+    while (!reader.atEnd()) {
+        switch (reader.readNext()) {
+        case QXmlStreamReader::StartElement:
+            elementCount++;
+            if (filterElement(reader.name())) {
+                const auto name = reader.name();
+                QXmlStreamAttributes attributes = reader.attributes();
+                filterAttributes(name, &attributes, &paragraphAlignmentFound);
+                writer.writeStartElement(name.toString());
+                if (!attributes.isEmpty())
+                    writer.writeAttributes(attributes);
+            } else {
+                reader.readElementText(); // Skip away all nested elements and characters.
+            }
+            break;
+        case QXmlStreamReader::Characters:
+            if (!isWhiteSpace(reader.text()))
+                writer.writeCharacters(reader.text().toString());
+            break;
+        case QXmlStreamReader::EndElement:
+            writer.writeEndElement();
+            break;
+        default:
+            break;
+        }
+    }
+    // Check for plain text (no spans, just <html><head><body><p>)
+    if (isPlainTextPtr)
+        *isPlainTextPtr = !paragraphAlignmentFound && elementCount == 4u; //
+    return out;
+}
+
+RichTextEditor::RichTextEditor(QWidget *parent)
+    : QTextEdit(parent), m_simplifyRichText(simplifyRichTextDefault)
+{
+    connect(this, &RichTextEditor::currentCharFormatChanged,
+            this, &RichTextEditor::stateChanged);
+    connect(this, &RichTextEditor::cursorPositionChanged,
+            this, &RichTextEditor::stateChanged);
+}
+
+QToolBar *RichTextEditor::createToolBar(QWidget *parent)
+{
+    return new RichTextEditorToolBar(this, parent);
+}
+
+void RichTextEditor::setFontBold(bool b)
+{
+    if (b)
+        setFontWeight(QFont::Bold);
+    else
+        setFontWeight(QFont::Normal);
+}
+
+void RichTextEditor::setFontPointSize(double d)
+{
+    QTextEdit::setFontPointSize(qreal(d));
+}
+
+void RichTextEditor::setText(const QString &text)
+{
+
+    if (Qt::mightBeRichText(text))
+        setHtml(text);
+    else
+        setPlainText(text);
+}
+
+void RichTextEditor::setSimplifyRichText(bool v)
+{
+    if (v != m_simplifyRichText) {
+        m_simplifyRichText = v;
+        emit simplifyRichTextChanged(v);
+    }
+}
+
+void RichTextEditor::setDefaultFont(QFont font)
+{
+    // Some default fonts on Windows have a default size of 7.8,
+    // which results in complicated rich text generated by toHtml().
+    // Use an integer value.
+    const int pointSize = qRound(font.pointSizeF());
+    if (pointSize > 0 && !qFuzzyCompare(qreal(pointSize), font.pointSizeF())) {
+        font.setPointSize(pointSize);
+    }
+
+    document()->setDefaultFont(font);
+    if (font.pointSize() > 0)
+        setFontPointSize(font.pointSize());
+    else
+        setFontPointSize(QFontInfo(font).pointSize());
+    emit textChanged();
+}
+
+QString RichTextEditor::text(Qt::TextFormat format) const
+{
+    switch (format) {
+    case Qt::PlainText:
+        return toPlainText();
+    case Qt::RichText:
+        return m_simplifyRichText ? simplifyRichTextFilter(toHtml()) : toHtml();
+    default:
+        break;
+    }
+    const QString html = toHtml();
+    bool isPlainText;
+    const QString simplifiedHtml = simplifyRichTextFilter(html, &isPlainText);
+    if (isPlainText)
+        return toPlainText();
+    return m_simplifyRichText ? simplifiedHtml : html;
+}