Correct/suggest command names with the help of damerau levenshtein distance

1 files changed, 96 insertions, 12 deletions

diff --git a/src/crsm.cpp b/src/crsm.cpp
index aa1ef13..e187123 100644
--- a/src/crsm.cpp
+++ b/src/crsm.cpp
@@ -245,6 +245,21 @@ bool CRSM::watchdog(const QString& id)
     return false;
 }
 
+QString CRSM::cmdErrorText(const QString& command, const ClientInfo& client, bool& ret)
+{
+    QString retText;
+    QStringList corrections;
+    if(!(ret = cmd(command, client, corrections)))
+    {
+        retText = "Unbekannter Befehl: \"" + command + "\"!\n";
+        if(!corrections.isEmpty())
+        {
+            retText += "Meintest du: " + corrections.join(", ") + "?\n";
+        }
+    }
+    return retText;
+}
+
 bool CRSM::clientMessage(ClientInfo& client, const QString& message, ClonkOutputInterface::MessageType type, const QTime& time)
 {
     bool isMeMessage = (type == Action);
@@ -281,11 +296,16 @@ bool CRSM::clientMessage(ClientInfo& client, const QString& message, ClonkOutput
             QString command = getCommand(message);
             if(!command.isEmpty())
             {
-                if(!cmd(command, client))
+                bool ret;
+                const QString& txt = cmdErrorText(command, client, ret);
+                if(ret)
+                {
+                    return true;
+                }
+                else
                 {
-                    respond(client, "Unbekannter Befehl: \"" + command + "\"!\n");
+                    respond(client, txt);
                 }
-                return true;
             }
         }
     }
@@ -699,7 +719,8 @@ void CRSM::newManagementData()
             if(data.at(0) == '/')
             {
                 QString command = data.mid(1).trimmed();
-                if(cmd(command, ClientInfo::managementClient(conn)))
+                QStringList corrections;
+                if(cmd(command, ClientInfo::managementClient(conn), corrections))
                 {
                     continue;
                 }
@@ -1431,12 +1452,58 @@ bool CRSM::cmdExists(const QString &name, ClientInterface interface)
     return cmds.contains(name) && cmds.value(name).interfaces & interface;
 }
 
-CmdFunctionRef* CRSM::findCommand(const QString &cmd, ClientInterface interface, QString &args)
+QStringList CRSM::guessCmd(const QString& name, ClientInterface interface)
+{
+    int minDistance = -1;
+    QString minDistanceCmd;
+    QStringList minDistanceCmds;
+
+    auto applyDistance = [&name, &minDistance, &minDistanceCmd, &minDistanceCmds](const QString& cmdName)
+    {
+        int distance = Util::damerauLevenshteinDistance(name, cmdName);
+        if(minDistance == -1 || distance < minDistance)
+        {
+            minDistance = distance;
+            minDistanceCmd = cmdName;
+            minDistanceCmds.clear();
+        }
+        else if(minDistance == distance && !minDistanceCmds.contains(cmdName))
+        {
+            minDistanceCmds.append(cmdName);
+        }
+    };
+
+    for(const auto& cmd : cmds)
+    {
+        if(cmd.interfaces & interface)
+        {
+            applyDistance(cmd.name);
+        }
+    }
+
+    for(const auto& alias : Config.CRSM.CommandAlias.keys())
+    {
+        applyDistance(alias);
+    }
+
+    if(!minDistanceCmds.contains(minDistanceCmd))
+    {
+        minDistanceCmds.append(minDistanceCmd);
+    }
+
+    if(minDistanceCmds.length() == 1 && minDistance >= std::min(3, name.length() - 1))
+    {
+        minDistanceCmds.clear();
+    }
+    return minDistanceCmds;
+}
+
+CmdFunctionRef* CRSM::findCommand(const QString &cmd, ClientInterface interface, QString &args, QStringList& corrections)
 {
-    return findCommand(cmd.split(QRegularExpression(R"(\s)"), QString::KeepEmptyParts), interface, args);
+    return findCommand(cmd.split(QRegularExpression(R"(\s)"), QString::KeepEmptyParts), interface, args, corrections);
 }
 
-CmdFunctionRef* CRSM::findCommand(QStringList&& cmd, ClientInterface interface, QString &realCmd)
+CmdFunctionRef* CRSM::findCommand(QStringList&& cmd, ClientInterface interface, QString &realCmd, QStringList& corrections)
 {
     if(cmd.length() > 0)
     {
@@ -1457,8 +1524,23 @@ CmdFunctionRef* CRSM::findCommand(QStringList&& cmd, ClientInterface interface,
             }
             else
             {
+                const QStringList& guesses = guessCmd(cmdPart, interface);
+                if(guesses.length() == 1)
+                {
+                    QString guess = guesses.first();
+                    substituteCommandAlias(guess);
+                    if(cmdExists(guess, interface))
+                    {
+                        return &cmds[guess];
+                    }
+                }
+                else if(guesses.length() > 1)
+                {
+                    corrections.append(guesses);
+                }
+
                 cmd.removeLast();
-                return findCommand(std::move(cmd), interface, realCmd);
+                return findCommand(std::move(cmd), interface, realCmd, corrections);
             }
         }
     }
@@ -1468,12 +1550,12 @@ CmdFunctionRef* CRSM::findCommand(QStringList&& cmd, ClientInterface interface,
     }
 }
 
-bool CRSM::cmd(const QString& cmd, const ClientInfo &client)
+bool CRSM::cmd(const QString& cmd, const ClientInfo &client, QStringList& corrections)
 {
     Log.commandLog(cmd, client, false);
     CmdFunctionRef* cmdPtr;
     QString realCmd = cmd;
-    if((cmdPtr = findCommand(cmd, client.interface, realCmd)) != nullptr)
+    if((cmdPtr = findCommand(cmd, client.interface, realCmd, corrections)) != nullptr)
     {
         CmdFunctionRef cmdRef = *cmdPtr;
         QString args = cmd.mid(realCmd.length()).trimmed();
@@ -2327,9 +2409,11 @@ void CRSM::handleIrcMessage(const ClientInfo &client, QString message, const QSt
 
     if(!command.isEmpty())
     {
-        if(!cmd(command, client))
+        bool ret;
+        const QString& txt = cmdErrorText(command, client, ret);
+        if(!ret)
         {
-            respond(client, "Unbekannter Befehl: \"" + command + "\"!", (privateMessage ? RespondType::PrivateNotice : RespondType::Normal), true);
+            respond(client, txt, (privateMessage ? RespondType::PrivateNotice : RespondType::Normal), true);
         }
     }