GH-3392 dirty initial MSA support that shares logic with Mojang flows

Both act as the first step of AuthContext.

launcher/minecraft/auth/AccountList.h

@@ -0,0 +1,118 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "MinecraftAccount.h"
+
+#include <QObject>
+#include <QVariant>
+#include <QAbstractListModel>
+#include <QSharedPointer>
+
+/*!
+ * List of available Mojang accounts.
+ * This should be loaded in the background by MultiMC on startup.
+ */
+class AccountList : public QAbstractListModel
+{
+    Q_OBJECT
+public:
+    enum ModelRoles
+    {
+        PointerRole = 0x34B1CB48
+    };
+
+    enum VListColumns
+    {
+        // TODO: Add icon column.
+        NameColumn = 0,
+        ProfileNameColumn,
+        TypeColumn,
+
+        NUM_COLUMNS
+    };
+
+    explicit AccountList(QObject *parent = 0);
+
+    const MinecraftAccountPtr at(int i) const;
+    int count() const;
+
+    //////// List Model Functions ////////
+    QVariant data(const QModelIndex &index, int role) const override;
+    virtual QVariant headerData(int section, Qt::Orientation orientation, int role) const override;
+    virtual int rowCount(const QModelIndex &parent) const override;
+    virtual int columnCount(const QModelIndex &parent) const override;
+    virtual Qt::ItemFlags flags(const QModelIndex &index) const override;
+    virtual bool setData(const QModelIndex &index, const QVariant &value, int role) override;
+
+    void addAccount(const MinecraftAccountPtr account);
+    void removeAccount(QModelIndex index);
+    int findAccountByProfileId(const QString &profileId) const;
+
+    /*!
+     * Sets the path to load/save the list file from/to.
+     * If autosave is true, this list will automatically save to the given path whenever it changes.
+     * THIS FUNCTION DOES NOT LOAD THE LIST. If you set autosave, be sure to call loadList() immediately
+     * after calling this function to ensure an autosaved change doesn't overwrite the list you intended
+     * to load.
+     */
+    void setListFilePath(QString path, bool autosave = false);
+
+    bool loadList();
+    bool loadV2(QJsonObject &root);
+    bool loadV3(QJsonObject &root);
+    bool saveList();
+
+    MinecraftAccountPtr activeAccount() const;
+    void setActiveAccount(const QString &profileId);
+    bool anyAccountIsValid();
+
+signals:
+    void listChanged();
+    void activeAccountChanged();
+
+public slots:
+    /**
+     * This is called when one of the accounts changes and the list needs to be updated
+     */
+    void accountChanged();
+
+protected:
+    /*!
+     * Called whenever the list changes.
+     * This emits the listChanged() signal and autosaves the list (if autosave is enabled).
+     */
+    void onListChanged();
+
+    /*!
+     * Called whenever the active account changes.
+     * Emits the activeAccountChanged() signal and autosaves the list if enabled.
+     */
+    void onActiveChanged();
+
+    QList<MinecraftAccountPtr> m_accounts;
+
+    MinecraftAccountPtr m_activeAccount;
+
+    //! Path to the account list file. Empty string if there isn't one.
+    QString m_listFilePath;
+
+    /*!
+     * If true, the account list will automatically save to the account list path when it changes.
+     * Ignored if m_listFilePath is blank.
+     */
+    bool m_autosave = false;
+};