Permission model

Add a model for managing permissions (power levels) in rooms. This gets rid of a whole bunch of boiler plate in NeoChat and as a bonus makes it easy to add a feature to allow setting the permission level for any event.

src/enums/powerlevel.h

@@ -0,0 +1,110 @@
+// SPDX-FileCopyrightText: 2024 James Graham <james.h.graham@protonmail.com>
+// SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
+
+#pragma once
+
+#include <QAbstractListModel>
+#include <QObject>
+#include <QQmlEngine>
+
+#include <KLocalizedString>
+
+/**
+ * @class PowerLevel
+ *
+ * This class is designed to define the PowerLevel enumeration.
+ */
+class PowerLevel : public QObject
+{
+    Q_OBJECT
+    QML_ELEMENT
+    QML_UNCREATABLE("")
+
+public:
+    /**
+     * @brief The type of delegate that is needed for the event.
+     *
+     * @note While similar this is not the matrix event or message type. This is
+     *       to tell a QML ListView what delegate to show for each event. So while
+     *       similar to the spec it is not the same.
+     */
+    enum Level {
+        Member, /**< A basic member. */
+        Moderator, /**< A moderator with enhanced powers. */
+        Admin, /**< The highest power level in the room. */
+        Mute, /**< The level to remove posting privileges. */
+        NUMLevels,
+        Custom, /**< A non-standard value. Intentionally after NUMLevels so it doesn't appear in the model. */
+    };
+    Q_ENUM(Level);
+
+    /**
+     * @brief Return a string representation of the enum value.
+     */
+    static QString nameForLevel(Level level);
+
+    /**
+     * @brief Return the integer representation of the enum value.
+     */
+    static int valueForLevel(Level level);
+
+    /**
+     * @brief Return the enum value for the given integer power level.
+     */
+    static Level levelForValue(int value);
+};
+
+/**
+ * @class PowerLevelModel
+ *
+ * A model visualize the allowed power levels.
+ */
+class PowerLevelModel : public QAbstractListModel
+{
+    Q_OBJECT
+    QML_ELEMENT
+
+    Q_PROPERTY(bool showMute READ showMute WRITE setShowMute NOTIFY showMuteChanged)
+
+public:
+    /**
+     * @brief Defines the model roles.
+     */
+    enum Roles {
+        NameRole = Qt::DisplayRole, /**< The power level name. */
+        ValueRole, /**< The power level value. */
+    };
+    Q_ENUM(Roles)
+
+    explicit PowerLevelModel(QObject *parent = nullptr);
+
+    [[nodiscard]] bool showMute() const;
+    void setShowMute(bool showMute);
+
+    /**
+     * @brief Get the given role value at the given index.
+     *
+     * @sa QAbstractItemModel::data
+     */
+    [[nodiscard]] QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
+
+    /**
+     * @brief Number of rows in the model.
+     *
+     * @sa  QAbstractItemModel::rowCount
+     */
+    [[nodiscard]] int rowCount(const QModelIndex &parent = QModelIndex()) const override;
+
+    /**
+     * @brief Returns a mapping from Role enum values to role names.
+     *
+     * @sa Roles, QAbstractItemModel::roleNames()
+     */
+    [[nodiscard]] QHash<int, QByteArray> roleNames() const override;
+
+Q_SIGNALS:
+    void showMuteChanged();
+
+private:
+    bool m_showMute = true;
+};