Ensure label entries to be unique for their cc/note

src/sfizz/SfzHelpers.h

@@ -7,6 +7,7 @@
 #pragma once
 #include <absl/types/optional.h>
 #include <absl/strings/string_view.h>
+#include <absl/algorithm/container.h>
 //#include <string>
 #include <array>
 #include <cmath>
@@ -202,6 +203,34 @@ inline CXX14_CONSTEXPR Type vaGain(Type cutoff, Type sampleRate)
     return std::tan(cutoff / sampleRate * pi<Type>());
 }
 
+/**
+ * @brief Insert an item uniquely into a vector of pairs.
+ *
+ * @param pairVector the vector of pairs
+ * @param key the unique key
+ * @param value the value
+ * @param replace whether to replace the value if the key is already present
+ * @return whether the item was inserted
+ */
+template <class P, class T, class U>
+bool insertPairUniquely(std::vector<P>& pairVector, const T& key, U value, bool replace = true)
+{
+    bool result = false;
+    auto it = absl::c_find_if(
+        pairVector, [&key](const P& pair) { return pair.first == key; });
+    if (it != pairVector.end()) {
+        if (replace) {
+            it->second = std::move(value);
+            result = true;
+        }
+    }
+    else {
+        pairVector.emplace_back(key, std::move(value));
+        result = true;
+    }
+    return result;
+}
+
 /**
  * @brief From a source view, find the next sfz header and its members and
  *          return them, while updating the source by removing this header

src/sfizz/Synth.cpp

@@ -233,8 +233,8 @@ void sfz::Synth::clear()
     hdcc(0, 10, 0.5f); // pan
 
     // set default controller labels
-    ccLabels.emplace_back(7, "Volume");
-    ccLabels.emplace_back(10, "Pan");
+    insertPairUniquely(ccLabels, 7, "Volume");
+    insertPairUniquely(ccLabels, 10, "Pan");
 }
 
 void sfz::Synth::handleMasterOpcodes(const std::vector<Opcode>& members)
@@ -336,12 +336,12 @@ void sfz::Synth::handleControlOpcodes(const std::vector<Opcode>& members)
             break;
         case hash("label_cc&"):
             if (Default::ccNumberRange.containsWithEnd(member.parameters.back()))
-                ccLabels.emplace_back(member.parameters.back(), std::string(member.value));
+                insertPairUniquely(ccLabels, member.parameters.back(), std::string(member.value));
             break;
         case hash("label_key&"):
             if (member.parameters.back() <= Default::keyRange.getEnd()) {
                 const auto noteNumber = static_cast<uint8_t>(member.parameters.back());
-                keyLabels.emplace_back(noteNumber, std::string(member.value));
+                insertPairUniquely(keyLabels, noteNumber, std::string(member.value));
             }
             break;
         case hash("default_path"):
@@ -545,7 +545,7 @@ void sfz::Synth::finalizeSfzLoad()
         }
 
         if (region->keyswitchLabel && region->keyswitch)
-            keyswitchLabels.push_back({ *region->keyswitch, *region->keyswitchLabel });
+            insertPairUniquely(keyswitchLabels, *region->keyswitch, *region->keyswitchLabel);
 
         // Some regions had group number but no "group-level" opcodes handled the polyphony
         while (polyphonyGroups.size() <= region->group) {