Refactor configuration system and modernize preferences UI

CMakeLists.txt

@@ -3,7 +3,7 @@ project(mmapper CXX)
 
 list(APPEND CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake)
 
-set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 

src/configuration/NamedConfig.h

@@ -3,32 +3,55 @@
 // Copyright (C) 2019 The MMapper Authors
 
 #include "../global/ChangeMonitor.h"
+#include "../global/Color.h"
+#include "../global/INamedConfig.h"
 
+#include <QString>
+#include <QColor>
+
+#include <algorithm>
+#include <cassert>
 #include <cmath>
+#include <functional>
 #include <string>
 #include <string_view>
 #include <type_traits>
 #include <vector>
 
 template<typename T>
-class NODISCARD NamedConfig final
+class NODISCARD NamedConfig final : public INamedConfig
 {
+public:
+    using OnAfterChange = std::function<void(const T &)>;
+
 private:
     std::string m_name;
     ChangeMonitor m_changeMonitor;
-    T m_value = 0;
+    T m_value;
+    OnAfterChange m_onAfterChange;
     bool m_notifying = false;
 
 public:
     NamedConfig() = delete;
     DELETE_CTORS_AND_ASSIGN_OPS(NamedConfig);
-    explicit NamedConfig(std::string name, T initialValue)
+
+    explicit NamedConfig(std::string name, T initialValue, OnAfterChange onAfterChange = nullptr)
         : m_name{std::move(name)}
         , m_value{std::move(initialValue)}
+        , m_onAfterChange{std::move(onAfterChange)}
     {}
 
+    explicit NamedConfig(std::string name, T initialValue, std::function<void()> simpleCallback)
+        : m_name{std::move(name)}
+        , m_value{std::move(initialValue)}
+    {
+        if (simpleCallback) {
+            m_onAfterChange = [cb = std::move(simpleCallback)](const T &) { cb(); };
+        }
+    }
+
 public:
-    NODISCARD const std::string &getName() { return m_name; }
+    NODISCARD const std::string &getName() const override { return m_name; }
     NODISCARD inline T get() const { return m_value; }
     void set(const T newValue)
     {
@@ -62,9 +85,21 @@ class NODISCARD NamedConfig final
         } notification_guard{*this};
 
         m_value = newValue;
+        if (m_onAfterChange) {
+            m_onAfterChange(m_value);
+        }
         m_changeMonitor.notifyAll();
     }
 
+    void setFromNotifier(std::function<void()> simpleCallback)
+    {
+        if (simpleCallback) {
+            m_onAfterChange = [cb = std::move(simpleCallback)](const T &) { cb(); };
+        } else {
+            m_onAfterChange = nullptr;
+        }
+    }
+
     void clamp(const T lo, const T hi)
     {
         // don't try to call this for boolean or string.
@@ -78,8 +113,82 @@ class NODISCARD NamedConfig final
     }
 
 public:
+    std::string toString() const override
+    {
+        if constexpr (std::is_same_v<T, std::string>) {
+            return m_value;
+        } else if constexpr (std::is_same_v<T, QString>) {
+            return m_value.toStdString();
+        } else if constexpr (std::is_same_v<T, bool>) {
+            return m_value ? "true" : "false";
+        } else if constexpr (std::is_integral_v<T> || std::is_floating_point_v<T>) {
+            return std::to_string(m_value);
+        } else if constexpr (std::is_same_v<T, Color>) {
+            return m_value.toHex();
+        } else if constexpr (std::is_same_v<T, QColor>) {
+            return m_value.name().toStdString();
+        } else if constexpr (std::is_same_v<T, QByteArray>) {
+            return m_value.toBase64().toStdString();
+        } else {
+            return "";
+        }
+    }
+
+    bool fromString(const std::string &str) override
+    {
+        if constexpr (std::is_same_v<T, std::string>) {
+            set(str);
+            return true;
+        } else if constexpr (std::is_same_v<T, QString>) {
+            set(QString::fromStdString(str));
+            return true;
+        } else if constexpr (std::is_same_v<T, bool>) {
+            if (str == "true" || str == "1" || str == "on") {
+                set(true);
+                return true;
+            } else if (str == "false" || str == "0" || str == "off") {
+                set(false);
+                return true;
+            }
+            return false;
+        } else if constexpr (std::is_integral_v<T>) {
+            try {
+                set(static_cast<T>(std::stoll(str)));
+                return true;
+            } catch (...) {
+                return false;
+            }
+        } else if constexpr (std::is_floating_point_v<T>) {
+            try {
+                set(static_cast<T>(std::stold(str)));
+                return true;
+            } catch (...) {
+                return false;
+            }
+        } else if constexpr (std::is_same_v<T, Color>) {
+            try {
+                set(Color::fromHex(str));
+                return true;
+            } catch (...) {
+                return false;
+            }
+        } else if constexpr (std::is_same_v<T, QColor>) {
+            QColor c(QString::fromStdString(str));
+            if (c.isValid()) {
+                set(c);
+                return true;
+            }
+            return false;
+        } else if constexpr (std::is_same_v<T, QByteArray>) {
+            set(QByteArray::fromBase64(QByteArray::fromStdString(str)));
+            return true;
+        } else {
+            return false;
+        }
+    }
+
     void registerChangeCallback(const ChangeMonitor::Lifetime &lifetime,
-                                ChangeMonitor::Function callback)
+                                ChangeMonitor::Function callback) override
     {
         return m_changeMonitor.registerChangeCallback(lifetime, std::move(callback));
     }