[Topic][Filter] Fixed topics matching when wildcard is involved

The correct behaviour is this:
- `*/In/*` and `Main/In/PING_TM` matches
- `*/Out/*` and `Main/In/PING_TM` does not

Previously, the wildcard was only used for the whole topic

src/shared/Core/Message/Topic.cpp

@@ -18,66 +18,67 @@
 
 #include "Topic.h"
 
+#include <qchar.h>
+#include <qglobal.h>
+
+#include <QDebug>
 #include <QRegExp>
 
-Topic::Topic() : topic("") {}
+Topic::Topic() : string("") {}
 
-Topic::Topic(QString topic) : topic(topic) {}
+Topic::Topic(QString topic) : string(topic)
+{
+    if (!isValid())
+        qWarning() << "Invalid topic created: " << topic;
+}
 
 bool Topic::operator==(const Topic& toCompare) const
 {
-    // Always true if the current topic is a pure wildcard
-    if (topic == "*" || topic == "?")
+    // Always true if one of the topics is a pure wildcard
+    if (string == "*" || toCompare.string == "*")
         return true;
 
-    // If the current topic isn't a wildcard then the topic must match
-    if (!isWildcard())
-        return topic == toCompare.toString();
+    // If the topics are equal, return true
+    if (string == toCompare.string)
+        return true;
 
-    // If the current topic is a wildcard then only the prefix must match
-    return toCompare.toString().startsWith(getPrefix().toString());
-}
+    auto our_stripped   = stripRoot();
+    auto their_stripped = toCompare.stripRoot();
 
-bool Topic::operator<(const Topic& toCompare) const
-{
-    return topic < toCompare.topic;
-}
+    // If one of them is a root topic, they must be different, since we already
+    // checked for equality
+    if (!our_stripped.has_value() || !their_stripped.has_value())
+        return false;
 
-Topic Topic::getParent() const
-{
-    int idx = topic.lastIndexOf('/');
-    return idx == -1 ? Topic(topic) : Topic(topic.left(idx));
+    // Otherwise, the roots and the stripped topics must be equal. Also, one of
+    // the stripped topics must not be null
+    return root() == toCompare.root() && our_stripped == their_stripped &&
+           (our_stripped.has_value() || their_stripped.has_value());
 }
 
-Topic Topic::getRoot() const
+Topic Topic::root() const
 {
-    int idx = topic.indexOf('/');
-    return idx == -1 ? Topic(topic) : Topic(topic.left(idx));
-}
+    int idx = string.indexOf('/');
 
-Topic Topic::getPrefix() const
-{
-    if (!isWildcard())
+    if (idx == -1)
         return *this;
-
-    int idxAst = topic.lastIndexOf('*');
-    int idxQue = topic.lastIndexOf('?');
-
-    int idx = idxAst != -1 ? idxAst : idxQue;
-
-    return Topic(topic.left(idx));
+    else
+        return Topic(string.left(idx));
 }
 
-bool Topic::isValid() const
+std::optional<Topic> Topic::stripRoot() const
 {
-    return topic.contains(QRegExp("^[A-Za-z0-9$_]+(\\/[A-Za-z0-9$_]+)*$"));
+    int idx = string.indexOf('/');
+
+    if (idx == -1)
+        return std::nullopt;
+    else
+        return Topic(string.right(string.length() - idx - 1));
 }
 
-bool Topic::isWildcard() const
+bool Topic::isValid() const
 {
-    // Check wether the last character is a wildcard
-    return topic.at(topic.size() - 1) == '*' ||
-           topic.at(topic.size() - 1) == '?';
+    return string.contains(QRegExp("^([\\w\\d*]+\\/)*[\\w\\d_*]*$"));
 }
 
-QString Topic::toString() const { return topic; }
+QString Topic::toString() const { return string; }

src/shared/Core/Message/Topic.h

@@ -18,58 +18,48 @@
 
 #pragma once
 
+#include <qchar.h>
+
 #include <QString>
+#include <optional>
 
 /**
  * @brief Topics are strings made of alphanumerical characters and slashes '/'.
  *
- * For example, "Prefix/Message" and "SomeMessage" are valid topics.
+ * For example, "Main/In/<asterix>", "SomeMessage", "*" are valid topics.
  */
-class Topic
+class Topic : QString
 {
 public:
     Topic();
     explicit Topic(QString topic);
 
     /**
-     * @brief Check if the given topic matches, also if the current is a
-     * wildcard.
+     * @brief Check if the given topic matches, considering wildcards.
      */
     bool operator==(const Topic& toCompare) const;
 
-    bool operator<(const Topic& toCompare) const;
-
-    /**
-     * @brief Returns the parent.
-     *
-     * If the topic is Prefix/Message, returns Prefix.
-     */
-    Topic getParent() const;
-
     /**
-     * @brief Returns the topic root.
-     *
-     * If the topic is Topic/SubTopic/SubSubTopic, returns Topic.
+     * @brief True if the topic is valid.
      */
-    Topic getRoot() const;
+    bool isValid() const;
 
-    /**
-     * @brief Removes the wildcard from a wildcard topic.
-     */
-    Topic getPrefix() const;
+    QString toString() const;
 
+private:
     /**
-     * @brief True if the topic is valid.
+     * @brief Get the root of the topic.
+     *
+     * For example, the root of "Main/In/<asterix>" is "Main".
      */
-    bool isValid() const;
+    Topic root() const;
 
     /**
-     * @brief Returns true if the topic is a wildcard.
+     * @brief Strip the root of the topic.
+     *
+     * For example, the root of "Main/In/<asterix>" is "In/<asterix>".
      */
-    bool isWildcard() const;
+    std::optional<Topic> stripRoot() const;
 
-    QString toString() const;
-
-private:
-    QString topic;
+    QString string;
 };