Implement a completer for commands

fixes #429

CMakeLists.txt

@@ -451,6 +451,8 @@ set(SRC_FILES
 	src/ColorImageProvider.h
 	src/CombinedImagePackModel.cpp
 	src/CombinedImagePackModel.h
+	src/CommandCompleter.cpp
+	src/CommandCompleter.h
 	src/CompletionModelRoles.h
 	src/CompletionProxyModel.cpp
 	src/CompletionProxyModel.h

resources/qml/Completer.qml

@@ -209,6 +209,30 @@ Control {
 
                 }
 
+                DelegateChoice {
+                    roleValue: "command"
+
+                    RowLayout {
+                        id: del
+
+                        anchors.centerIn: parent
+                        spacing: rowSpacing
+
+                        Label {
+                            text: model.name
+                            color: model.index == popup.currentIndex ? Nheko.colors.highlightedText : Nheko.colors.text
+                            font.bold: true
+                        }
+
+                        Label {
+                            text: model.description
+                            color: model.index == popup.currentIndex ? Nheko.colors.highlightedText : Nheko.colors.buttonText
+                        }
+
+                    }
+
+                }
+
                 DelegateChoice {
                     roleValue: "customEmoji"
 

resources/qml/MessageInput.qml

@@ -168,6 +168,8 @@ Rectangle {
                         messageInput.openCompleter(selectionStart-1, "roomAliases");
                     } else if (lastChar == "~") {
                         messageInput.openCompleter(selectionStart-1, "customEmoji");
+                    } else if (lastChar == "/" && cursorPosition == 1) {
+                        messageInput.openCompleter(selectionStart-1, "command");
                     }
                 }
                 onCursorPositionChanged: {

src/CommandCompleter.cpp

@@ -0,0 +1,222 @@
+// SPDX-FileCopyrightText: 2021 Nheko Contributors
+// SPDX-FileCopyrightText: 2022 Nheko Contributors
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "CommandCompleter.h"
+
+#include "CompletionModelRoles.h"
+
+CommandCompleter::CommandCompleter(QObject *parent)
+  : QAbstractListModel(parent)
+{
+}
+
+QHash<int, QByteArray>
+CommandCompleter::roleNames() const
+{
+    return {
+      {CompletionModel::CompletionRole, "completionRole"},
+      {CompletionModel::SearchRole, "searchRole"},
+      {CompletionModel::SearchRole2, "searchRole2"},
+      {Roles::Name, "name"},
+      {Roles::Description, "description"},
+    };
+}
+
+QVariant
+CommandCompleter::data(const QModelIndex &index, int role) const
+{
+    if (hasIndex(index.row(), index.column(), index.parent())) {
+        switch (role) {
+        case CompletionModel::CompletionRole:
+            // append space where applicable in a completion
+            switch (index.row()) {
+            case Me:
+                return QString("/me ");
+            case React:
+                return QString("/react ");
+            case Join:
+                return QString("/join ");
+            case Knock:
+                return QString("/knock ");
+            case Part:
+                return QString("/part ");
+            case Leave:
+                return QString("/leave ");
+            case Invite:
+                return QString("/invite @");
+            case Kick:
+                return QString("/kick @");
+            case Ban:
+                return QString("/ban @");
+            case Unban:
+                return QString("/unban @");
+            case Redact:
+                return QString("/redact ");
+            case Roomnick:
+                return QString("/roomnick ");
+            case Shrug:
+                return QString("/shrug");
+            case Fliptable:
+                return QString("/fliptable");
+            case Unfliptable:
+                return QString("/unfliptable");
+            case Sovietflip:
+                return QString("/sovietflip");
+            case ClearTimeline:
+                return QString("/clear-timeline");
+            case ResetState:
+                return QString("/reset-state");
+            case RotateMegolmSession:
+                return QString("/rotate-megolm-session");
+            case Md:
+                return QString("/md ");
+            case Plain:
+                return QString("/plain ");
+            case Rainbow:
+                return QString("/rainbow ");
+            case RainbowMe:
+                return QString("/rainbowme ");
+            case Notice:
+                return QString("/notice ");
+            case RainbowNotice:
+                return QString("/rainbownotice ");
+            case Goto:
+                return QString("/goto ");
+            case ConvertToDm:
+                return QString("/converttodm");
+            case ConvertToRoom:
+                return QString("/converttoroom");
+            default:
+                return {};
+            }
+        case CompletionModel::SearchRole:
+        case Qt::DisplayRole:
+        case Roles::Name:
+            switch (index.row()) {
+            case Me:
+                return tr("/me <message>");
+            case React:
+                return tr("/react <text>");
+            case Join:
+                return tr("/join (!roomid|#alias) [reason]");
+            case Knock:
+                return tr("/knock (!roomid|#alias) [reason]");
+            case Part:
+                return tr("/part [reason]");
+            case Leave:
+                return tr("/leave [reason]");
+            case Invite:
+                return tr("/invite @userid [reason]");
+            case Kick:
+                return tr("/kick @userid [reason]");
+            case Ban:
+                return tr("/ban @userid [reason]");
+            case Unban:
+                return tr("/unban @userid [reason]");
+            case Redact:
+                return tr("/redact ($eventid|@userid)");
+            case Roomnick:
+                return tr("/roomnick <displayname>");
+            case Shrug:
+                return tr("/shrug [message]");
+            case Fliptable:
+                return tr("/fliptable");
+            case Unfliptable:
+                return tr("/unfliptable");
+            case Sovietflip:
+                return tr("/sovietflip");
+            case ClearTimeline:
+                return tr("/clear-timeline");
+            case ResetState:
+                return tr("/reset-state");
+            case RotateMegolmSession:
+                return tr("/rotate-megolm-session");
+            case Md:
+                return tr("/md [message]");
+            case Plain:
+                return tr("/plain [message]");
+            case Rainbow:
+                return tr("/rainbow [message]");
+            case RainbowMe:
+                return tr("/rainbowme [message]");
+            case Notice:
+                return tr("/notice [message]");
+            case RainbowNotice:
+                return tr("/rainbownotice [message]");
+            case Goto:
+                return tr("/goto ($eventid|message index|matrix:r/room/e/event)");
+            case ConvertToDm:
+                return tr("/converttodm");
+            case ConvertToRoom:
+                return tr("/converttoroom");
+            default:
+                return {};
+            }
+        case CompletionModel::SearchRole2:
+        case Roles::Description:
+            switch (index.row()) {
+            case Me:
+                return tr("Send a message expressing an action.");
+            case React:
+                return tr("Send <text> as a reaction when you’re replying to a message.");
+            case Join:
+                return tr("Join a room. Reason is optional.");
+            case Knock:
+                return tr("Ask to join a room. Reason is optional.");
+            case Part:
+                return tr("Leave a room. Reason is optional.");
+            case Leave:
+                return tr("Leave a room. Reason is optional.");
+            case Invite:
+                return tr("Invite a user into the current room. Reason is optional.");
+            case Kick:
+                return tr("Kick a user from the current room. Reason is optional.");
+            case Ban:
+                return tr("Ban a user from the current room. Reason is optional.");
+            case Unban:
+                return tr("Unban a user in the current room. Reason is optional.");
+            case Redact:
+                return tr("Redact an event or all locally cached messages of a user.");
+            case Roomnick:
+                return tr("Change your displayname in this room.");
+            case Shrug:
+                return tr("¯\\_(ツ)_/¯ with an optional message.");
+            case Fliptable:
+                return tr("(╯°□°)╯︵ ┻━┻");
+            case Unfliptable:
+                return tr("┯━┯╭( º _ º╭)");
+            case Sovietflip:
+                return tr("ノ┬─┬ノ ︵ ( \\o°o)\\");
+            case ClearTimeline:
+                return tr("Clear the currently cached messages in this room.");
+            case ResetState:
+                return tr("Refetch the state in this room.");
+            case RotateMegolmSession:
+                return tr("Rotate the current symmetric encryption key.");
+            case Md:
+                return tr("Send a markdown formatted message (ignoring the global setting).");
+            case Plain:
+                return tr("Send an unformatted message (ignoring the global setting).");
+            case Rainbow:
+                return tr("Send a message in rainbow colors.");
+            case RainbowMe:
+                return tr("Send /me in rainbow colors.");
+            case Notice:
+                return tr("Send a bot message.");
+            case RainbowNotice:
+                return tr("Send a bot message in rainbow colors.");
+            case Goto:
+                return tr("Go to this event or link.");
+            case ConvertToDm:
+                return tr("Convert this room to a direct chat.");
+            case ConvertToRoom:
+                return tr("Convert this direct chat into a room.");
+            default:
+                return {};
+            }
+        }
+    }
+    return {};
+}

src/CommandCompleter.h

@@ -0,0 +1,61 @@
+// SPDX-FileCopyrightText: 2021 Nheko Contributors
+// SPDX-FileCopyrightText: 2022 Nheko Contributors
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include <QAbstractListModel>
+#include <QString>
+
+class CommandCompleter final : public QAbstractListModel
+{
+public:
+    enum Roles
+    {
+        Name = Qt::UserRole,
+        Description,
+    };
+
+    enum Commands
+    {
+        Me,
+        React,
+        Join,
+        Knock,
+        Part,
+        Leave,
+        Invite,
+        Kick,
+        Ban,
+        Unban,
+        Redact,
+        Roomnick,
+        Shrug,
+        Fliptable,
+        Unfliptable,
+        Sovietflip,
+        ClearTimeline,
+        ResetState,
+        RotateMegolmSession,
+        Md,
+        Plain,
+        Rainbow,
+        RainbowMe,
+        Notice,
+        RainbowNotice,
+        Goto,
+        ConvertToDm,
+        ConvertToRoom,
+        COUNT,
+    };
+
+    CommandCompleter(QObject *parent = nullptr);
+    QHash<int, QByteArray> roleNames() const override;
+    int rowCount(const QModelIndex &parent = QModelIndex()) const override
+    {
+        (void)parent;
+        return (int)Commands::COUNT;
+    }
+    QVariant data(const QModelIndex &index, int role) const override;
+};

src/RoomsModel.cpp

@@ -7,6 +7,7 @@
 
 #include <QUrl>
 
+#include "Cache.h"
 #include "Cache_p.h"
 #include "CompletionModelRoles.h"
 #include "UserSettingsPage.h"

src/RoomsModel.h

@@ -5,7 +5,7 @@
 
 #pragma once
 
-#include "Cache.h"
+#include "CacheStructs.h"
 
 #include <QAbstractListModel>
 #include <QString>

src/timeline/TimelineViewManager.cpp

@@ -12,6 +12,7 @@
 
 #include "ChatPage.h"
 #include "CombinedImagePackModel.h"
+#include "CommandCompleter.h"
 #include "CompletionProxyModel.h"
 #include "EventAccessors.h"
 #include "ImagePackListModel.h"
@@ -443,6 +444,11 @@ TimelineViewManager::completerFor(const QString &completerName, const QString &r
         auto proxy        = new CompletionProxyModel(stickerModel);
         stickerModel->setParent(proxy);
         return proxy;
+    } else if (completerName == QLatin1String("command")) {
+        static auto commandCompleter = new CommandCompleter();
+        auto proxy                   = new CompletionProxyModel(commandCompleter);
+        commandCompleter->setParent(proxy);
+        return proxy;
     }
     return nullptr;
 }