Don't allow adding unique effect (like fades) twice

src/assets/abstractassetsrepository.hpp

@@ -49,6 +49,9 @@ public:
 
     /* @brief Return type of asset */
     AssetType getType(const QString &assetId) const;
+    
+    /* @brief Return type of asset */
+    bool isUnique(const QString &assetId) const;
 
     /* @brief Return name of asset */
     Q_INVOKABLE QString getName(const QString &assetId) const;

src/assets/abstractassetsrepository.ipp

@@ -286,6 +286,14 @@ template <typename AssetType> AssetType AbstractAssetsRepository<AssetType>::get
     return m_assets.at(assetId).type;
 }
 
+template <typename AssetType> bool AbstractAssetsRepository<AssetType>::isUnique(const QString &assetId) const
+{
+    if (m_assets.count(assetId) > 0) {
+        return m_assets.at(assetId).xml.hasAttribute(QStringLiteral("unique"));
+    }
+    return false;
+}
+
 template <typename AssetType> QString AbstractAssetsRepository<AssetType>::getName(const QString &assetId) const
 {
     Q_ASSERT(m_assets.count(assetId) > 0);

src/effects/effectstack/model/abstracteffectitem.hpp

@@ -53,6 +53,8 @@ public:
 
     /* @brief Return true if the effect or effect group applies only to audio */
     virtual bool isAudio() const = 0;
+    /* @brief Return true if this effect can only have one instance in an effect stack */
+    virtual bool isUnique() const = 0;
 
     /* @brief This function plants the effect into the given service in last position
      */

src/effects/effectstack/model/effectgroupmodel.cpp

@@ -60,6 +60,11 @@ bool EffectGroupModel::isAudio() const
     return result;
 }
 
+bool EffectGroupModel::isUnique() const
+{
+    return false;
+}
+
 void EffectGroupModel::plant(const std::weak_ptr<Mlt::Service> &service)
 {
     for (int i = 0; i < childCount(); ++i) {

src/effects/effectstack/model/effectgroupmodel.hpp

@@ -39,6 +39,7 @@ public:
 
     /* @brief Return true if the effect applies only to audio */
     bool isAudio() const override;
+    bool isUnique() const override;
 
     /* @brief This function plants the effect into the given service in last position
      */

src/effects/effectstack/model/effectitemmodel.cpp

@@ -223,3 +223,8 @@ bool EffectItemModel::isAudio() const
     AssetListType::AssetType type = EffectsRepository::get()->getType(m_assetId);
     return  type == AssetListType::AssetType::Audio || type == AssetListType::AssetType::CustomAudio;
 }
+
+bool EffectItemModel::isUnique() const
+{
+    return EffectsRepository::get()->isUnique(m_assetId);
+}

src/effects/effectstack/model/effectitemmodel.hpp

@@ -57,6 +57,7 @@ public:
 
     /* @brief Return true if the effect applies only to audio */
     bool isAudio() const override;
+    bool isUnique() const override;
 
     void setCollapsed(bool collapsed);
     bool isCollapsed();

src/effects/effectstack/model/effectstackmodel.cpp

@@ -284,6 +284,10 @@ bool EffectStackModel::fromXml(const QDomElement &effectsXml, Fun &undo, Fun &re
         } else if (state != PlaylistState::VideoOnly) {
             continue;
         }
+        if (EffectsRepository::get()->isUnique(effectId) && hasEffect(effectId))  {
+            pCore->displayMessage(i18n("Effect %1 cannot be added twice.", EffectsRepository::get()->getName(effectId)), InformationMessage);
+            return false;
+        }
         bool effectEnabled = true;
         if (Xml::hasXmlProperty(node, QLatin1String("disable"))) {
             effectEnabled = Xml::getXmlProperty(node, QLatin1String("disable")).toInt() != 1;
@@ -365,6 +369,10 @@ bool EffectStackModel::copyEffect(const std::shared_ptr<AbstractEffectItem> &sou
     }
     std::shared_ptr<EffectItemModel> sourceEffect = std::static_pointer_cast<EffectItemModel>(sourceItem);
     const QString effectId = sourceEffect->getAssetId();
+    if (EffectsRepository::get()->isUnique(effectId) && hasEffect(effectId))  {
+        pCore->displayMessage(i18n("Effect %1 cannot be added twice.", EffectsRepository::get()->getName(effectId)), InformationMessage);
+        return false;
+    }
     bool enabled = sourceEffect->isEnabled();
     auto effect = EffectItemModel::construct(effectId, shared_from_this(), enabled);
     effect->setParameters(sourceEffect->getAllParameters());
@@ -408,6 +416,10 @@ bool EffectStackModel::copyEffect(const std::shared_ptr<AbstractEffectItem> &sou
 bool EffectStackModel::appendEffect(const QString &effectId, bool makeCurrent)
 {
     QWriteLocker locker(&m_lock);
+    if (EffectsRepository::get()->isUnique(effectId) && hasEffect(effectId))  {
+        pCore->displayMessage(i18n("Effect %1 cannot be added twice.", EffectsRepository::get()->getName(effectId)), InformationMessage);
+        return false;
+    }
     std::unordered_set<int> previousFadeIn = m_fadeIns;
     std::unordered_set<int> previousFadeOut = m_fadeOuts;
     if (EffectsRepository::get()->isGroup(effectId)) {
@@ -915,6 +927,10 @@ void EffectStackModel::importEffects(const std::weak_ptr<Mlt::Service> &service,
                 continue;
             }
             const QString effectId = qstrdup(filter->get("kdenlive_id"));
+            if (EffectsRepository::get()->isUnique(effectId) && hasEffect(effectId))  {
+                pCore->displayMessage(i18n("Effect %1 cannot be added twice.", EffectsRepository::get()->getName(effectId)), InformationMessage);
+                continue;
+            }
             if (filter->get_int("disable") == 0) {
                 effectEnabled = true;
             }
@@ -1293,3 +1309,13 @@ bool EffectStackModel::hasKeyFrame(int frame)
     std::shared_ptr<KeyframeModelList> listModel = sourceEffect->getKeyframeModel();
     return listModel->hasKeyframe(frame);
 }
+
+bool EffectStackModel::hasEffect(const QString &assetId) const
+{
+    for (int i = 0; i < rootItem->childCount(); ++i) {
+        if (std::static_pointer_cast<EffectItemModel>(rootItem->child(i))->getAssetId() == assetId) {
+            return true;
+        }
+    }
+    return false;
+}

src/effects/effectstack/model/effectstackmodel.hpp

@@ -142,6 +142,9 @@ public:
     /* @brief This is a convenience function that helps check if the tree is in a valid state */
     bool checkConsistency() override;
 
+    /* @brief Return true if an asset id is already added to this effect stack */
+    bool hasEffect(const QString &assetId) const;
+
 public slots:
     /* @brief Delete an effect from the stack */
     void removeEffect(const std::shared_ptr<EffectItemModel> &effect);