saveload.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef TSAGE_SAVELOAD_H
#define TSAGE_SAVELOAD_H

#include "common/scummsys.h"
#include "common/list.h"
#include "common/memstream.h"
#include "common/savefile.h"
#include "common/serializer.h"

namespace TsAGE {

typedef void (*SaveNotifierFn)(bool postFlag);

#define TSAGE_SAVEGAME_VERSION 15

class SavedObject;

struct tSageSavegameHeader {
    uint8 _version;
    Common::String _saveName;
    Graphics::Surface *_thumbnail;
    int _saveYear, _saveMonth, _saveDay;
    int _saveHour, _saveMinutes;
    int _totalFrames;
};

/*--------------------------------------------------------------------------*/

// FIXME: workaround to suppress spurious strict-alias warnings on older GCC
// versions. this should be resolved with the savegame rewrite
#define SYNC_POINTER(x) do { \
    SavedObject **y = (SavedObject **)((void *)&x); \
    s.syncPointer(y); \
} while (false)

#define SYNC_ENUM(FIELD, TYPE) int v_##FIELD = (int)FIELD; s.syncAsUint16LE(v_##FIELD); \
    if (s.isLoading()) FIELD = (TYPE)v_##FIELD;

class Serializer : public Common::Serializer {
public:
    Serializer(Common::SeekableReadStream *in, Common::WriteStream *out) : Common::Serializer(in, out) {}

    // HACK: TSAGE saved games contain a single byte for the savegame version,
    // thus the normal syncVersion() Serializer member won't work here. In order
    // to maintain compatibility with older game saves, this method is provided
    // in order to set the savegame version from a byte
    void setSaveVersion(byte version) { _version = version; }

    void syncPointer(SavedObject **ptr, Common::Serializer::Version minVersion = 0,
        Common::Serializer::Version maxVersion = kLastVersion);
    void validate(const Common::String &s, Common::Serializer::Version minVersion = 0,
        Common::Serializer::Version maxVersion = kLastVersion);
    void validate(int v, Common::Serializer::Version minVersion = 0,
        Common::Serializer::Version maxVersion = kLastVersion);
    void syncAsDouble(double &v);
};

/*--------------------------------------------------------------------------*/

class Serialisable {
public:
    virtual ~Serialisable() {}
    virtual void synchronize(Serializer &s) = 0;
};

class SaveListener {
public:
    virtual ~SaveListener() {}
    virtual void listenerSynchronize(Serializer &s) = 0;
};

/*--------------------------------------------------------------------------*/

class SavedObject : public Serialisable {
public:
    SavedObject();
    ~SavedObject() override;

    virtual Common::String getClassName() { return "SavedObject"; }
    void synchronize(Serializer &s) override {}

    static SavedObject *createInstance(const Common::String &className);
};

/*--------------------------------------------------------------------------*/

template<typename T>
class SynchronizedList : public Common::List<T> {
public:
    void synchronize(Serializer &s) {
        int entryCount = 0;

        if (s.isLoading()) {
            this->clear();
            s.syncAsUint32LE(entryCount);

            for (int idx = 0; idx < entryCount; ++idx) {
                this->push_back(static_cast<T>((T)NULL));
                T &obj = Common::List<T>::back();
                s.syncPointer((SavedObject **)&obj);
            }
        } else {
            // Get the list size
            entryCount = this->size();

            // Write out list
            s.syncAsUint32LE(entryCount);
            for (typename Common::List<T>::iterator i = this->begin(); i != this->end(); ++i) {
                s.syncPointer((SavedObject **)&*i);
            }
        }
    }

    void addBefore(T existingItem, T newItem) {
        typename SynchronizedList<T>::iterator i = this->begin();
        while ((i != this->end()) && (*i != existingItem)) ++i;
        this->insert(i, newItem);
    }
    void addAfter(T existingItem, T newItem) {
        typename SynchronizedList<T>::iterator i = this->begin();
        while ((i != this->end()) && (*i != existingItem)) ++i;
        if (i != this->end()) ++i;
        this->insert(i, newItem);
    }

    bool contains(T item) {
        typename SynchronizedList<T>::iterator i = this->begin();
        for (; i != this->end(); ++i) {
            if (*i == item)
                return true;
        }

        return false;
    }
};

template<typename T>
inline bool contains(const Common::List<T> &l, const T &v) {
    return (Common::find(l.begin(), l.end(), v) != l.end());
}

template<typename T>
class FunctionList : public Common::List<void (*)(T)> {
public:
    void notify(T v) {
        for (typename Common::List<void (*)(T)>::iterator i = this->begin(); i != this->end(); ++i) {
            (*i)(v);
        }
    }
};

/*--------------------------------------------------------------------------*/

class SavedObjectRef {
public:
    SavedObject **_savedObject;
    int _objIndex;

    SavedObjectRef() : _savedObject(NULL), _objIndex(-1) {}
    SavedObjectRef(SavedObject **so, int objIndex) : _savedObject(so),  _objIndex(objIndex) {}
};

typedef SavedObject *(*SavedObjectFactory)(const Common::String &className);

class Saver {
    typedef Common::List<SavedObject *> DynObjects;
private:
    Common::List<SavedObject *> _objList;
    FunctionList<bool> _saveNotifiers;
    FunctionList<bool> _loadNotifiers;
    Common::List<SaveListener *> _listeners;

    Common::List<SavedObjectRef> _unresolvedPtrs;
    SavedObjectFactory _factoryPtr;

    bool _macroSaveFlag;
    bool _macroRestoreFlag;

    void resolveLoadPointers(DynObjects &dynObjects);
public:
    Saver();
    ~Saver();

    Common::Error save(int slot, const Common::String &saveName);
    Common::Error restore(int slot);
    WARN_UNUSED_RESULT static bool readSavegameHeader(Common::InSaveFile *in, tSageSavegameHeader &header, bool skipThumbnail = true);
    static void writeSavegameHeader(Common::OutSaveFile *out, tSageSavegameHeader &header);

    void addListener(SaveListener *obj);
    void addSaveNotifier(SaveNotifierFn fn);
    void addLoadNotifier(SaveNotifierFn fn);
    void addObject(SavedObject *obj);
    void removeObject(SavedObject *obj);
    void addFactory(SavedObjectFactory fn) { _factoryPtr = fn; }
    void addSavedObjectPtr(SavedObject **ptr, int objIndex) {
        _unresolvedPtrs.push_back(SavedObjectRef(ptr, objIndex));
    }

    bool savegamesExist() const;
    bool getMacroSaveFlag() const { return _macroSaveFlag; }
    bool getMacroRestoreFlag() const { return _macroRestoreFlag; }
    int blockIndexOf(SavedObject *p);
    int getObjectCount() const;
    void listObjects();
};

extern Saver *g_saver;

} // End of namespace TsAGE

#endif