don't update the deckhash on load

add a new property to decklists that tracks if the deck needs to update
the deckhash

only update the deckhash if needed when it is asked for

this saves computing the deckhash for every loaded deck as performed by
the visual deck selector with impunity

the copy constructor also now no longer computes the deck hash again

the deck hash is now only computed once, on deck load, as expected,
resulting in massive amounts of cpu cycles not being wasted

common/decklist.cpp

@@ -361,15 +361,14 @@ QVector<QPair<int, int>> InnerDecklistNode::sort(Qt::SortOrder order)
     return result;
 }
 
-DeckList::DeckList()
+DeckList::DeckList() : QObject(), deckHashDirty(true)
 {
     root = new InnerDecklistNode;
 }
 
 // TODO: https://qt-project.org/doc/qt-4.8/qobject.html#no-copy-constructor-or-assignment-operator
 DeckList::DeckList(const DeckList &other)
-    : QObject(), name(other.name), comments(other.comments), bannerCard(other.bannerCard), deckHash(other.deckHash),
-      lastLoadedTimestamp(other.lastLoadedTimestamp), tags(other.tags)
+    : QObject(), name(other.name), comments(other.comments), bannerCard(other.bannerCard), deckHash(other.deckHash), deckHashDirty(other.deckHashDirty), lastLoadedTimestamp(other.lastLoadedTimestamp), tags(other.tags)
 {
     root = new InnerDecklistNode(other.getRoot());
 
@@ -378,10 +377,9 @@ DeckList::DeckList(const DeckList &other)
         spIterator.next();
         sideboardPlans.insert(spIterator.key(), new SideboardPlan(spIterator.key(), spIterator.value()->getMoveList()));
     }
-    updateDeckHash();
 }
 
-DeckList::DeckList(const QString &nativeString)
+DeckList::DeckList(const QString &nativeString) : QObject()
 {
     root = new InnerDecklistNode;
     loadFromString_Native(nativeString);
@@ -507,7 +505,8 @@ bool DeckList::loadFromXml(QXmlStreamReader *xml)
             }
         }
     }
-    updateDeckHash();
+    deckHashDirty = true;
+    emit deckHashChanged();
     if (xml->error()) {
         qDebug() << "Error loading deck from xml: " << xml->errorString();
         return false;
@@ -734,7 +733,8 @@ bool DeckList::loadFromStream_Plain(QTextStream &in)
         new DecklistCardNode(cardName, amount, getZoneObjFromName(zoneName), setCode, collectorNumber);
     }
 
-    updateDeckHash();
+    deckHashDirty = true;
+    emit deckHashChanged();
     return true;
 }
 
@@ -809,6 +809,7 @@ void DeckList::cleanList()
     setComments();
     setTags();
     deckHash = QString();
+    deckHashDirty = false;
     emit deckHashChanged();
 }
 
@@ -881,7 +882,8 @@ DecklistCardNode *DeckList::addCard(const QString &cardName,
     }
 
     auto *node = new DecklistCardNode(cardName, 1, zoneNode, cardSetName, cardSetCollectorNumber, cardProviderId);
-    updateDeckHash();
+    deckHashDirty = true;
+    emit deckHashChanged();
 
     return node;
 }
@@ -907,7 +909,8 @@ bool DeckList::deleteNode(AbstractDecklistNode *node, InnerDecklistNode *rootNod
         }
 
         if (updateHash) {
-            updateDeckHash();
+            deckHashDirty = true;
+            emit deckHashChanged();
         }
 
         return true;
@@ -918,7 +921,8 @@ bool DeckList::deleteNode(AbstractDecklistNode *node, InnerDecklistNode *rootNod
         if (inner) {
             if (deleteNode(node, inner)) {
                 if (updateHash) {
-                    updateDeckHash();
+                    deckHashDirty = true;
+                    emit deckHashChanged();
                 }
 
                 return true;
@@ -929,6 +933,14 @@ bool DeckList::deleteNode(AbstractDecklistNode *node, InnerDecklistNode *rootNod
     return false;
 }
 
+QString DeckList::getDeckHash()
+{
+    if (deckHashDirty) {
+        updateDeckHash();
+    }
+    return deckHash;
+}
+
 void DeckList::updateDeckHash()
 {
     QStringList cardList;
@@ -955,7 +967,7 @@ void DeckList::updateDeckHash()
                      (((quint64)(unsigned char)deckHashArray[1]) << 24) +
                      (((quint64)(unsigned char)deckHashArray[2] << 16)) +
                      (((quint64)(unsigned char)deckHashArray[3]) << 8) + (quint64)(unsigned char)deckHashArray[4];
-    deckHash = QString::number(number, 32).rightJustified(8, '0');
 
-    emit deckHashChanged();
+    deckHash = QString::number(number, 32).rightJustified(8, '0');
+    deckHashDirty = false;
 }

common/decklist.h

@@ -253,6 +253,7 @@ private:
     QString name, comments;
     QPair<QString, QString> bannerCard;
     QString deckHash;
+    bool deckHashDirty;
     QString lastLoadedTimestamp;
     QStringList tags;
     QMap<QString, SideboardPlan *> sideboardPlans;
@@ -363,10 +364,7 @@ public:
 
     int getSideboardSize() const;
 
-    QString getDeckHash() const
-    {
-        return deckHash;
-    }
+    QString getDeckHash();
     void updateDeckHash();
 
     InnerDecklistNode *getRoot() const
@@ -399,4 +397,4 @@ public:
     }
 };
 
-#endif
+#endif