qt: Add media history manager for recently used images

src/qt/qt_mediahistorymanager.hpp

@@ -0,0 +1,139 @@
+/*
+* 86Box	A hypervisor and IBM PC system emulator that specializes in
+*		running old operating systems and software designed for IBM
+*		PC systems and compatibles from 1981 through fairly recent
+*		system designs based on the PCI bus.
+*
+*		This file is part of the 86Box distribution.
+*
+*		Header for the media history management module
+*
+*
+*
+* Authors:	cold-brewed
+*
+*		Copyright 2022 The 86Box development team
+*/
+
+#ifndef QT_MEDIAHISTORYMANAGER_HPP
+#define QT_MEDIAHISTORYMANAGER_HPP
+
+#include <QString>
+#include <QWidget>
+#include <QVector>
+
+#include <initializer_list>
+
+extern "C" {
+#include <86box/86box.h>
+}
+
+// This macro helps give us the required `qHash()` function in order to use the
+// enum as a hash key
+#define QHASH_FOR_CLASS_ENUM(T) \
+inline uint qHash(const T &t, uint seed) { \
+    return ::qHash(static_cast<typename std::underlying_type<T>::type>(t), seed); \
+}
+
+typedef QVector<QString>             device_index_list_t;
+typedef QHash<int, QVector<QString>> device_media_history_t;
+
+
+namespace ui {
+    Q_NAMESPACE
+    
+    enum class MediaType {
+        Floppy,
+        Optical,
+        Zip,
+        Mo,
+        Cassette
+    };
+    // This macro allows us to do a reverse lookup of the enum with `QMetaEnum`
+    Q_ENUM_NS(MediaType)
+    
+    QHASH_FOR_CLASS_ENUM(MediaType)
+
+    typedef QHash<ui::MediaType, device_media_history_t> master_list_t;
+
+    // Used to iterate over all supported types when preparing data structures
+    // Also useful to indicate which types support history
+    static const MediaType AllSupportedMediaHistoryTypes[] = {
+        MediaType::Optical
+    };
+
+    class MediaHistoryManager {
+
+    public:
+        MediaHistoryManager();
+        virtual ~MediaHistoryManager();
+
+        // Get the image name for a particular slot,
+        // index, and type combination
+        QString getImageForSlot(int index, int slot, ui::MediaType type);
+
+        // Add an image to history
+        void addImageToHistory(int index, ui::MediaType type, const QString& image_name, const QString& new_image_name);
+
+        // Convert the enum value to a string
+        static QString mediaTypeToString(ui::MediaType type);
+
+        // Clear out the image history
+        void clearImageHistory();
+
+
+    private:
+        int max_images = MAX_PREV_IMAGES;
+
+        // Main hash of hash of vector of strings
+        master_list_t       master_list;
+        const master_list_t &getMasterList() const;
+        void                 setMasterList(const master_list_t &masterList);
+
+        device_index_list_t index_list, empty_device_index_list;
+
+        // Return a blank, initialized image history list
+        master_list_t &blankImageHistory(master_list_t &initialized_master_list) const;
+
+        // Initialize the image history
+        void initializeImageHistory();
+
+        // Max number of devices supported by media type
+        static int maxDevicesSupported(ui::MediaType type);
+
+        // Serialize the data back into the C array
+        // on the emu side
+        void serializeImageHistoryType(ui::MediaType type);
+        void serializeAllImageHistory();
+
+        // Deserialize the data from C array on the emu side
+        // for the ui side
+        void deserializeImageHistoryType(ui::MediaType type);
+        void deserializeAllImageHistory();
+
+        // Get emu history variable for a device type
+        static char** getEmuHistoryVarForType(ui::MediaType type, int index);
+
+        // Get or set the history for a specific device/index combo
+        const device_index_list_t &getHistoryListForDeviceIndex(int index, ui::MediaType type);
+        void setHistoryListForDeviceIndex(int index, ui::MediaType type, device_index_list_t history_list);
+
+        // Remove missing image files from history list
+        static device_index_list_t &removeMissingImages(device_index_list_t &device_history);
+
+        // If an absolute path is contained within `usr_path`, convert to a relative path
+        static device_index_list_t &pathAdjustFull(device_index_list_t &device_history);
+        static QString pathAdjustSingle(QString checked_path);
+
+        // Deduplicate history entries
+        static device_index_list_t &deduplicateList(device_index_list_t &device_history, const QVector<QString>& filenames);
+        void initialDeduplication();
+
+        // Gets the `usr_path` from the emu side and appends a
+        // trailing slash if necessary
+        static QString getUsrPath();
+    };
+
+} // ui
+
+#endif // QT_MEDIAHISTORYMANAGER_HPP