feat: [sidebar/settings] custom settings can be added.

as title.
now you can add your custom setting item into setting pane, and you can
customize it's order.

Log: custom setting pane.

Task: https://pms.uniontech.com/task-view-286565.html?onlybody=yes

include/dfm-base/settingdialog/customsettingitemregister.h

@@ -0,0 +1,30 @@
+// SPDX-FileCopyrightText: 2023 UnionTech Software Technology Co., Ltd.
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef CUSTOMSETTINGITEMREGISTER_H
+#define CUSTOMSETTINGITEMREGISTER_H
+
+#include <QMap>
+#include <QPair>
+
+class QWidget;
+class QObject;
+
+typedef QPair<QWidget *, QWidget *> (*CustomSettingItemCreator)(QObject *);
+
+namespace dfmbase {
+class CustomSettingItemRegister
+{
+public:
+    static CustomSettingItemRegister *instance();
+    bool registCustomSettingItemType(const QString &type, const CustomSettingItemCreator &creator);
+    const QMap<QString, CustomSettingItemCreator> &getCreators() const;
+
+private:
+    CustomSettingItemRegister();
+    QMap<QString, CustomSettingItemCreator> creators;
+};
+}
+
+#endif   // CUSTOMSETTINGITEMREGISTER_H

include/dfm-base/settingdialog/settingjsongenerator.h

@@ -0,0 +1,72 @@
+// SPDX-FileCopyrightText: 2023 UnionTech Software Technology Co., Ltd.
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef SETTINGJSONGENERATOR_H
+#define SETTINGJSONGENERATOR_H
+
+#include <QVariantMap>
+
+/*
+ * the root group:
+ * {
+ *      "groups": [(top level group)]
+ * }
+ *
+ * a top level group:
+ * {
+ *      "key": (string),
+ *      "name": (string),
+ *      "groups": [(config group)]
+ * }
+ *
+ * a config group:
+ * {
+ *      "key": (string),
+ *      "name": (string),
+ *      "options": [(config item)]
+ * }
+ *
+ * config item: // option item
+ * {
+ *      "key": (string),
+ *      "text": (string),
+ *      "type": (string),
+ *      "default": (variant),
+ *      "hide": (bool),
+ *      "custom_info": (variant)
+ * }
+ * */
+
+namespace dfmbase {
+
+class SettingJsonGenerator
+{
+public:
+    static SettingJsonGenerator *instance();
+
+    QByteArray genSettingJson();
+    bool addGroup(const QString &key, const QString &name);
+    bool addConfig(const QString &key, const QVariantMap &config);
+    bool addCheckBoxConfig(const QString &key, const QString &text, bool defaultVal = true);
+    bool addComboboxConfig(const QString &key, const QString &name, const QStringList &options, int defaultVal = 0);
+    bool addComboboxConfig(const QString &key, const QString &name, const QVariantMap &options, QVariant defaultVal = QVariant());
+
+protected:
+    SettingJsonGenerator();
+
+    void mergeGroups();
+    QJsonObject constructTopGroup(const QString &key);
+    QJsonObject constructConfigGroup(const QString &key);
+    QJsonObject constructConfig(const QString &key);
+
+private:
+    QMap<QString, QString> topGroups;
+    QMap<QString, QString> tmpTopGroups;
+    QMap<QString, QString> configGroups;
+    QMap<QString, QString> tmpConfigGroups;
+    QMap<QString, QVariantMap> configs;
+};
+
+}
+#endif   // SETTINGJSONGENERATOR_H

src/dfm-base/base/configs/customsettingitemregister.cpp

@@ -0,0 +1,34 @@
+// SPDX-FileCopyrightText: 2023 UnionTech Software Technology Co., Ltd.
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "dfm-base/settingdialog/customsettingitemregister.h"
+
+#include <QDebug>
+
+using namespace dfmbase;
+
+CustomSettingItemRegister::CustomSettingItemRegister()
+{
+}
+
+const QMap<QString, CustomSettingItemCreator> &CustomSettingItemRegister::getCreators() const
+{
+    return creators;
+}
+
+CustomSettingItemRegister *CustomSettingItemRegister::instance()
+{
+    static CustomSettingItemRegister ins;
+    return &ins;
+}
+
+bool CustomSettingItemRegister::registCustomSettingItemType(const QString &type, const CustomSettingItemCreator &creator)
+{
+    if (creators.contains(type)) {
+        qWarning() << type << "is already registered...";
+        return false;
+    }
+    creators.insert(type, creator);
+    return true;
+}

src/dfm-base/base/configs/settingbackend.h

@@ -40,6 +40,8 @@ class SettingBackend : public DSettingsBackend
     void doSetOption(const QString &key, const QVariant &value);
     void onValueChanged(int attribute, const QVariant &value);
 
+    void initPresetSettingConfig();
+
 private:
     explicit SettingBackend(QObject *parent = nullptr);
     ~SettingBackend();

src/dfm-base/base/configs/settingjsongenerator.cpp

@@ -0,0 +1,208 @@
+// SPDX-FileCopyrightText: 2023 UnionTech Software Technology Co., Ltd.
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "dfm-base/settingdialog/settingjsongenerator.h"
+
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QJsonArray>
+
+#include <QDebug>
+
+using namespace dfmbase;
+
+SettingJsonGenerator::SettingJsonGenerator()
+{
+}
+
+SettingJsonGenerator *SettingJsonGenerator::instance()
+{
+    static SettingJsonGenerator gen;
+    return &gen;
+}
+
+QByteArray SettingJsonGenerator::genSettingJson()
+{
+    mergeGroups();
+
+    QJsonArray groups;
+    auto iter = topGroups.cbegin();
+    while (iter != topGroups.cend()) {
+        groups.append(constructTopGroup(iter.key()));
+        iter++;
+    }
+
+    QJsonObject obj;
+    obj.insert("groups", groups);
+
+    QJsonDocument doc;
+    doc.setObject(obj);
+    return doc.toJson(QJsonDocument::Indented);
+}
+
+bool SettingJsonGenerator::addGroup(const QString &key, const QString &name)
+{
+    if (key.count(".") > 1) {
+        qWarning() << "max group level is 2, inputed: " << key.count(".") << key;
+        return false;
+    }
+    if (key.startsWith(".") || key.endsWith(".")) {
+        qWarning() << "the dot must not be start or end of the key." << key;
+        return false;
+    }
+
+    if (key.contains(".")) {
+        if (configGroups.contains(key)) {
+            qWarning() << "same name key has been added:" << key << ":" << configGroups.value(key);
+            return false;
+        }
+        configGroups.insert(key, name);
+
+        // check if top group exist.
+        QString topGroup = key.split(".").first();
+        if (!topGroups.contains(topGroup)) {
+            qWarning() << "no top group exist: " << topGroup;
+            tmpTopGroups.insert(topGroup, topGroup);
+        }
+    } else {
+        if (topGroups.contains(key)) {
+            qWarning() << "same name key has been added: " << key << ":" << topGroups.value(key);
+            return false;
+        }
+        topGroups.insert(key, name);
+    }
+
+    return true;
+}
+
+bool SettingJsonGenerator::addConfig(const QString &key, const QVariantMap &config)
+{
+    if (key.count(".") != 2) {
+        qWarning() << "config can only be inserted in level 2:" << key;
+        return false;
+    }
+    if (key.startsWith(".") || key.endsWith(".")) {
+        qWarning() << "the dot must not be start or end of the key." << key;
+        return false;
+    }
+    if (key.contains("..")) {
+        qWarning() << "cannot insert config into empty group: " << key;
+        return false;
+    }
+    if (configs.contains(key)) {
+        qWarning() << "a same name key is already added." << key << ":" << configs.value(key);
+        return false;
+    }
+
+    QStringList frags = key.split(".");
+    if (frags.count() != 3)
+        return false;
+    QString configKey = frags.at(2);
+    if (config.value("key").toString() != configKey) {
+        qWarning() << "config is not valid with key" << key << config;
+        return false;
+    }
+
+    frags.removeLast();
+    tmpConfigGroups.insert(frags.join("."), frags.last());
+    frags.removeLast();
+    tmpTopGroups.insert(frags.first(), frags.first());
+
+    configs.insert(key, config);
+    return true;
+}
+
+bool SettingJsonGenerator::addCheckBoxConfig(const QString &key, const QString &text, bool defaultVal)
+{
+    QVariantMap config {
+        { "key", key.mid(key.lastIndexOf(".") + 1) },
+        { "text", text },
+        { "type", "checkbox" },
+        { "default", defaultVal }
+    };
+    return addConfig(key, config);
+}
+
+bool SettingJsonGenerator::addComboboxConfig(const QString &key, const QString &name, const QStringList &options, int defaultVal)
+{
+    QVariantMap config {
+        { "key", key.mid(key.lastIndexOf(".") + 1) },
+        { "name", name },
+        { "items", options },
+        { "type", "combobox" },
+        { "default", defaultVal }
+    };
+    return addConfig(key, config);
+}
+
+bool SettingJsonGenerator::addComboboxConfig(const QString &key, const QString &name, const QVariantMap &options, QVariant defaultVal)
+{
+    QVariantMap config {
+        { "key", key.mid(key.lastIndexOf(".") + 1) },
+        { "name", name },
+        { "items", options },
+        { "type", "combobox" },
+        { "default", defaultVal }
+    };
+    return addConfig(key, config);
+}
+
+void SettingJsonGenerator::mergeGroups()
+{
+    auto merge = [](const QMap<QString, QString> &from, QMap<QString, QString> &into) {
+        auto iter = from.cbegin();
+        while (iter != from.cend()) {
+            if (!into.contains(iter.key()))
+                into.insert(iter.key(), iter.value());
+            iter++;
+        }
+    };
+    merge(tmpConfigGroups, configGroups);
+    merge(tmpTopGroups, topGroups);
+}
+
+QJsonObject SettingJsonGenerator::constructTopGroup(const QString &key)
+{
+    qDebug() << "construct top group:" << key;
+    QJsonObject obj;
+    obj.insert("key", key);
+    obj.insert("name", topGroups.value(key, "Unknown"));
+
+    QJsonArray groups;
+    auto iter = configGroups.cbegin();
+    while (iter != configGroups.cend()) {
+        if (iter.key().startsWith(key))
+            groups.append(constructConfigGroup(iter.key()));
+        iter++;
+    }
+
+    obj.insert("groups", groups);
+    return obj;
+}
+
+QJsonObject SettingJsonGenerator::constructConfigGroup(const QString &key)
+{
+    qDebug() << "construct config group:" << key;
+    QJsonObject obj;
+    obj.insert("key", key.mid(key.indexOf(".") + 1));
+    obj.insert("name", configGroups.value(key, "Unknown"));
+
+    QJsonArray options;
+    auto iter = configs.cbegin();
+    while (iter != configs.cend()) {
+        if (iter.key().startsWith(key))
+            options.append(constructConfig(iter.key()));
+        iter++;
+    }
+
+    obj.insert("options", options);
+    return obj;
+}
+
+QJsonObject SettingJsonGenerator::constructConfig(const QString &key)
+{
+    qDebug() << "construct item: " << key;
+    QVariantMap config = configs.value(key, QVariantMap());
+    return QJsonObject::fromVariantMap(config);
+}