feat: derive a sender's avatar initials

1 files changed, 78 insertions, 0 deletions

diff --git a/src/avatar.cpp b/src/avatar.cpp
new file mode 100644
index 0000000..4cedae2
--- /dev/null
+++ b/src/avatar.cpp
@@ -0,0 +1,78 @@
+/*
+ * qtmaildir - a Qt6 mail client for notmuch-indexed Maildirs
+ * Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "avatar.h"
+
+#include <QCryptographicHash>
+#include <QPainter>
+#include <QPainterPath>
+
+namespace {
+
+QString twoFrom(const QString &text)
+{
+    const QString trimmed = text.trimmed();
+    if (trimmed.size() >= 2)
+        return trimmed.left(2).toUpper();
+    if (trimmed.size() == 1)
+        return (trimmed + trimmed).toUpper();
+    return QString();
+}
+
+} // namespace
+
+namespace Avatar {
+
+QString initialsFor(const QString &displayName, const QString &address,
+                    const QString &accountLabel)
+{
+    const QStringList words = displayName.split(QLatin1Char(' '),
+                                                Qt::SkipEmptyParts);
+    if (words.size() >= 2) {
+        return (words.at(0).left(1) + words.at(1).left(1)).toUpper();
+    }
+    if (words.size() == 1) {
+        const QString one = twoFrom(words.at(0));
+        if (!one.isEmpty())
+            return one;
+    }
+
+    // No usable name. The local part and the domain each give one letter,
+    // which never degrades to a single letter the way the local part alone
+    // would, and never reads as a truncated word.
+    const int at = address.indexOf(QLatin1Char('@'));
+    if (at > 0) {
+        const QString local = address.left(at).trimmed();
+        const QString domain = address.mid(at + 1).trimmed();
+        if (!local.isEmpty() && !domain.isEmpty())
+            return (local.left(1) + domain.left(1)).toUpper();
+    }
+    // An address with no `@` is still something to show.
+    const QString bare = twoFrom(address);
+    if (!bare.isEmpty())
+        return bare;
+
+    const QString account = twoFrom(accountLabel);
+    if (!account.isEmpty())
+        return account;
+
+    // Nothing at all. Two characters regardless, so the shape never breaks.
+    return QStringLiteral("??");
+}
+
+} // namespace Avatar