workspace: handle duplicate output hashes correctly

Some outputs have the same EDID, which results in two connected outputs
having the same hash. To find out which config values need to be used,
also check the connector name.

src/workspace.cpp

@@ -563,16 +563,42 @@ QMap<Output *, QJsonObject> outputsConfig(const QVector<Output *> &outputs, cons
         return {};
     }
 
+    QHash<Output *, bool> duplicate;
+    QHash<Output *, QString> outputHashes;
+    for (Output *output : outputs) {
+        const QString hash = outputHash(output);
+        const auto it = std::find_if(outputHashes.cbegin(), outputHashes.cend(), [hash](const auto &value) {
+            return value == hash;
+        });
+        if (it == outputHashes.cend()) {
+            duplicate[output] = false;
+        } else {
+            duplicate[output] = true;
+            duplicate[it.key()] = true;
+        }
+        outputHashes[output] = hash;
+    }
+
     QMap<Output *, QJsonObject> ret;
     const auto outputsJson = doc.array();
     for (const auto &outputJson : outputsJson) {
         const auto outputObject = outputJson.toObject();
-        for (auto it = outputs.constBegin(), itEnd = outputs.constEnd(); it != itEnd;) {
-            if (!ret.contains(*it) && outputObject["id"] == outputHash(*it)) {
-                ret[*it] = outputObject;
-                continue;
+        const auto id = outputObject["id"];
+        const auto output = std::find_if(outputs.begin(), outputs.end(), [&duplicate, &id, &outputObject](Output *output) {
+            if (outputHash(output) != id.toString()) {
+                return false;
             }
-            ++it;
+            if (duplicate[output]) {
+                // can't distinguish between outputs by hash alone, need to look at connector names
+                const auto metadata = outputObject[QStringLiteral("metadata")];
+                const auto outputName = metadata[QStringLiteral("name")].toString();
+                return outputName == output->name();
+            } else {
+                return true;
+            }
+        });
+        if (output != outputs.end()) {
+            ret[*output] = outputObject;
         }
     }
     return ret;