Improve search element

src/akonadi-contacts/contactsfilterproxymodel.cpp

@@ -19,6 +19,32 @@ using namespace Akonadi;
 static bool contactMatchesFilter(const KContacts::Addressee &contact, const QString &filterString, ContactsFilterProxyModel::MatchFilterContactFlag flag);
 static bool contactGroupMatchesFilter(const KContacts::ContactGroup &group, const QString &filterString);
 
+static QString normalize(QStringView str)
+{
+    QString out;
+    out.reserve(str.size());
+    for (const auto c : str) {
+        // case folding
+        const auto n = c.toCaseFolded();
+
+        // if the character has a canonical decomposition use that and skip the
+        // combining diacritic markers following it
+        // see https://en.wikipedia.org/wiki/Unicode_equivalence
+        // see https://en.wikipedia.org/wiki/Combining_character
+        if (n.decompositionTag() == QChar::Canonical) {
+            out.push_back(n.decomposition().at(0));
+        }
+        // handle compatibility compositions such as ligatures
+        // see https://en.wikipedia.org/wiki/Unicode_compatibility_characters
+        else if (n.decompositionTag() == QChar::Compat && n.isLetter() && n.script() == QChar::Script_Latin) {
+            out.append(n.decomposition());
+        } else {
+            out.push_back(n);
+        }
+    }
+    return out;
+}
+
 class Akonadi::ContactsFilterProxyModelPrivate
 {
 public:
@@ -63,7 +89,7 @@ bool ContactsFilterProxyModel::filterAcceptsRow(int row, const QModelIndex &pare
     if ((d->mFilter.isEmpty()) && (!(d->flags & ContactsFilterProxyModel::HasEmail))) {
         return true;
     }
-
+    const QString filterStr = normalize(d->mFilter);
     const auto item = index.data(Akonadi::EntityTreeModel::ItemRole).value<Akonadi::Item>();
 
     if (item.hasPayload<KContacts::Addressee>()) {
@@ -74,13 +100,13 @@ bool ContactsFilterProxyModel::filterAcceptsRow(int row, const QModelIndex &pare
             }
         }
         if (!d->mFilter.isEmpty()) {
-            return contactMatchesFilter(contact, d->mFilter, d->matchFilterFlag);
+            return contactMatchesFilter(contact, filterStr, d->matchFilterFlag);
         }
     } else {
         if (!d->mFilter.isEmpty()) {
             if (item.hasPayload<KContacts::ContactGroup>()) {
                 const auto group = item.payload<KContacts::ContactGroup>();
-                return contactGroupMatchesFilter(group, d->mFilter);
+                return contactGroupMatchesFilter(group, filterStr);
             }
         }
     }
@@ -173,15 +199,15 @@ static bool addressMatchesFilter(const KContacts::Address &address, const QStrin
 
 static bool contactMatchesFilter(const KContacts::Addressee &contact, const QString &filterString, ContactsFilterProxyModel::MatchFilterContactFlag flag)
 {
-    if (contact.assembledName().contains(filterString, Qt::CaseInsensitive)) {
+    if (normalize(contact.assembledName()).contains(filterString, Qt::CaseInsensitive)) {
         return true;
     }
 
-    if (contact.formattedName().contains(filterString, Qt::CaseInsensitive)) {
+    if (normalize(contact.formattedName()).contains(filterString, Qt::CaseInsensitive)) {
         return true;
     }
 
-    if (contact.nickName().contains(filterString, Qt::CaseInsensitive)) {
+    if (normalize(contact.nickName()).contains(filterString, Qt::CaseInsensitive)) {
         return true;
     }
 
@@ -210,7 +236,7 @@ static bool contactMatchesFilter(const KContacts::Addressee &contact, const QStr
     const QStringList emails = contact.emails();
     count = emails.count();
     for (int i = 0; i < count; ++i) {
-        if (emails.at(i).contains(filterString, Qt::CaseInsensitive)) {
+        if (normalize(emails.at(i)).contains(filterString, Qt::CaseInsensitive)) {
             return true;
         }
     }
@@ -227,7 +253,7 @@ static bool contactMatchesFilter(const KContacts::Addressee &contact, const QStr
             return true;
         }
 
-        if (contact.title().contains(filterString, Qt::CaseInsensitive)) {
+        if (normalize(contact.title()).contains(filterString, Qt::CaseInsensitive)) {
             return true;
         }
 
@@ -235,15 +261,15 @@ static bool contactMatchesFilter(const KContacts::Addressee &contact, const QStr
             return true;
         }
 
-        if (contact.organization().contains(filterString, Qt::CaseInsensitive)) {
+        if (normalize(contact.organization()).contains(filterString, Qt::CaseInsensitive)) {
             return true;
         }
 
-        if (contact.department().contains(filterString, Qt::CaseInsensitive)) {
+        if (normalize(contact.department()).contains(filterString, Qt::CaseInsensitive)) {
             return true;
         }
 
-        if (contact.note().contains(filterString, Qt::CaseInsensitive)) {
+        if (normalize(contact.note()).contains(filterString, Qt::CaseInsensitive)) {
             return true;
         }
 
@@ -265,16 +291,16 @@ static bool contactMatchesFilter(const KContacts::Addressee &contact, const QStr
 
 bool contactGroupMatchesFilter(const KContacts::ContactGroup &group, const QString &filterString)
 {
-    if (group.name().contains(filterString, Qt::CaseInsensitive)) {
+    if (normalize(group.name()).contains(filterString, Qt::CaseInsensitive)) {
         return true;
     }
 
     const int count = group.dataCount();
     for (int i = 0; i < count; ++i) {
-        if (group.data(i).name().contains(filterString, Qt::CaseInsensitive)) {
+        if (normalize(group.data(i).name()).contains(filterString, Qt::CaseInsensitive)) {
             return true;
         }
-        if (group.data(i).email().contains(filterString, Qt::CaseInsensitive)) {
+        if (normalize(group.data(i).email()).contains(filterString, Qt::CaseInsensitive)) {
             return true;
         }
     }