Audit best practice 0.4.8: orientazioni per pagina (reader in landscape), licenza nel pacchetto, EPUB lazy lengths, cover dinamica (ReaderState), flush config senza sync per tasto, pulizia chapterFraction/commenti

src/epub.cpp

@@ -490,8 +490,14 @@ bool EpubBook::open(const QString &epubPath)
     if (!parseOpf())
         return false;
     const bool ok = !m_chapters.isEmpty();
-    if (ok)
-        computeTextLengths();
+    if (ok) {
+        // lunghezze testo LAZY: -1 = da calcolare al primo accesso. L'apertura
+        // resta veloce anche per libri grossi (niente parse di tutti i capitoli).
+        m_textLengths.clear();
+        m_textLengths.reserve(m_chapters.size());
+        for (int i = 0; i < m_chapters.size(); ++i)
+            m_textLengths.append(-1);
+    }
     emit changed();
     return ok;
 }
@@ -763,24 +769,26 @@ QString EpubBook::chapterRichText(int index) const
     return htmlToRichText(html);
 }
 
-void EpubBook::computeTextLengths()
+// calcola (e cache) la lunghezza del capitolo index se non ancora nota
+void EpubBook::ensureTextLength(int index) const
 {
-    m_textLengths.clear();
-    for (const EpubChapter &c : m_chapters) {
-        QFile f(c.path);
-        if (!f.open(QIODevice::ReadOnly)) {
-            m_textLengths.append(0);
-            continue;
-        }
-        const QString html = QString::fromUtf8(f.readAll());
-        m_textLengths.append(plainTextLength(html));
+    if (index < 0 || index >= m_textLengths.size() || m_textLengths.at(index) >= 0)
+        return;
+    const EpubChapter &c = m_chapters.at(index);
+    QFile f(c.path);
+    if (!f.open(QIODevice::ReadOnly)) {
+        m_textLengths[index] = 0;
+        return;
     }
+    const QString html = QString::fromUtf8(f.readAll());
+    m_textLengths[index] = plainTextLength(html);
 }
 
 int EpubBook::chapterTextLength(int index) const
 {
     if (index < 0 || index >= m_textLengths.size())
         return 0;
+    ensureTextLength(index);
     return m_textLengths.at(index);
 }
 
@@ -788,8 +796,10 @@ qint64 EpubBook::chapterStartChar(int index) const
 {
     qint64 start = 0;
     const int end = qMin(index, m_textLengths.size());
-    for (int i = 0; i < end; ++i)
+    for (int i = 0; i < end; ++i) {
+        ensureTextLength(i);
         start += m_textLengths.at(i);
+    }
     return start;
 }