#ifndef AMUSE_PROJECT_MODEL_HPP
#define AMUSE_PROJECT_MODEL_HPP

#include <QAbstractItemModel>
#include <QIdentityProxyModel>
#include <QDir>
#include <QIcon>
#include <map>
#include "Common.hpp"
#include "NewSoundMacroDialog.hpp"
#include "amuse/AudioGroup.hpp"
#include "amuse/AudioGroupData.hpp"
#include "amuse/AudioGroupProject.hpp"
#include "amuse/AudioGroupPool.hpp"
#include "amuse/AudioGroupSampleDirectory.hpp"

class ProjectModel;

class NullItemProxyModel : public QIdentityProxyModel
{
    Q_OBJECT
public:
    explicit NullItemProxyModel(ProjectModel* source);
    QModelIndex mapFromSource(const QModelIndex& sourceIndex) const;
    QModelIndex mapToSource(const QModelIndex& proxyIndex) const;
    int rowCount(const QModelIndex& parent) const;
    QModelIndex index(int row, int column, const QModelIndex& parent) const;
    QVariant data(const QModelIndex& proxyIndex, int role) const;
};

class PageObjectProxyModel : public QIdentityProxyModel
{
    Q_OBJECT
public:
    explicit PageObjectProxyModel(ProjectModel* source);
    QModelIndex mapFromSource(const QModelIndex& sourceIndex) const;
    QModelIndex mapToSource(const QModelIndex& proxyIndex) const;
    QModelIndex parent(const QModelIndex& child) const;
    int rowCount(const QModelIndex& parent) const;
    QModelIndex index(int row, int column, const QModelIndex& parent) const;
    QVariant data(const QModelIndex& proxyIndex, int role) const;
    Qt::ItemFlags flags(const QModelIndex& proxyIndex) const;
};

class ProjectModel : public QAbstractItemModel
{
    Q_OBJECT
public:
    enum class ImportMode
    {
        Original,
        WAVs,
        Both
    };

    struct NameUndoRegistry
    {
        std::unordered_map<amuse::SongId, std::string> m_songIDs;
        std::unordered_map<amuse::SFXId, std::string> m_sfxIDs;
        void registerSongName(amuse::SongId id) const;
        void unregisterSongName(amuse::SongId id);
        void registerSFXName(amuse::SongId id) const;
        void unregisterSFXName(amuse::SongId id);
        void clear()
        {
            m_songIDs.clear();
            m_sfxIDs.clear();
        }
    };

private:
    QDir m_dir;
    NullItemProxyModel m_nullProxy;
    PageObjectProxyModel m_pageObjectProxy;

    amuse::ProjectDatabase m_projectDatabase;
    std::unordered_map<QString, std::unique_ptr<amuse::AudioGroupDatabase>> m_groups;

    struct Song
    {
        QString m_path;
        int m_refCount = 0;
    };
    std::unordered_map<amuse::SongId, Song> m_midiFiles;

public:
    class INode : public amuse::IObj
    {
    public:
        enum class Type
        {
            Null,
            Root,
            Group, // Top-level group
            SongGroup,
            SoundGroup,
            Collection, // Classified object collection, one of the following:
            SoundMacro,
            ADSR,
            Curve,
            Keymap,
            Layer,
            Sample
        };
    protected:
        QString m_name;
        INode* m_parent = nullptr;
        int m_row = -1;
        std::vector<amuse::IObjToken<INode>> m_children;
        amuse::IObjToken<INode> m_nullChild;
    public:
        virtual ~INode() = default;
        INode(const QString& name);
        INode(INode* parent) : m_parent(parent), m_row(0)
        {
            /* ONLY USED BY NULL NODE! */
        }

        int childCount() const { return int(m_children.size()); }
        INode* child(int row) const
        {
            if (row == m_children.size())
                return nullChild();
            return m_children[row].get();
        }
        INode* nullChild() const { return m_nullChild.get(); }
        INode* parent() const { return m_parent; }
        int row() const { return m_row; }

        void reindexRows(int row)
        {
            for (auto it = m_children.begin() + row; it != m_children.end(); ++it)
                (*it)->m_row = row++;
            m_nullChild->m_row = row;
        }

        void insertChild(amuse::ObjToken<INode> n)
        {
            assert(n->m_parent == nullptr && "Inserting already-parented node");
            n->m_parent = this;
            int row = hypotheticalIndex(n->name());
            m_children.insert(m_children.begin() + row, n.get());
            reindexRows(row);
        }
        amuse::ObjToken<INode> removeChild(INode* n)
        {
            int row = n->row();
            assert(n == m_children.at(row).get() && "Removing non-child from node");
            m_children.erase(m_children.begin() + row);
            reindexRows(row);
            n->m_parent = nullptr;
            n->m_row = -1;
            return n;
        }

        void reserve(size_t sz) { m_children.reserve(sz); }
        template<class T, class... _Args>
        T& makeChild(_Args&&... args)
        {
            auto tok = amuse::MakeObj<T>(std::forward<_Args>(args)...);
            insertChild(tok.get());
            return static_cast<T&>(*tok);
        }
        template<class T, class... _Args>
        T& _appendChild(_Args&&... args)
        {
            auto tok = amuse::MakeObj<T>(std::forward<_Args>(args)...);
            tok->m_parent = this;
            tok->m_row = m_children.size();
            m_children.push_back(tok.get());
            m_nullChild->m_row = m_children.size();
            return static_cast<T&>(*tok);
        }

        bool depthTraverse(const std::function<bool(INode* node)>& func)
        {
            for (auto& n : m_children)
                if (!n->depthTraverse(func))
                    break;
            return func(this);
        }

        bool oneLevelTraverse(const std::function<bool(INode* node)>& func)
        {
            for (auto& n : m_children)
                if (!func(n.get()))
                    return false;
            return true;
        }

        const QString& name() const { return m_name; }
        virtual int hypotheticalIndex(const QString& name) const;

        virtual Type type() const = 0;
        virtual QString text() const = 0;
        virtual QIcon icon() const = 0;
        virtual Qt::ItemFlags flags() const { return Qt::ItemIsEnabled | Qt::ItemIsSelectable; }

        virtual void registerNames(const NameUndoRegistry& registry) const {}
        virtual void unregisterNames(NameUndoRegistry& registry) const {}
    };
    struct NullNode : INode
    {
        NullNode(INode* parent) : INode(parent) {}

        Type type() const { return Type::Null; }
        QString text() const { return {}; }
        QIcon icon() const { return {}; }
    };
    struct RootNode : INode
    {
        RootNode() : INode(QStringLiteral("<root>")) {}

        Type type() const { return Type::Root; }
        QString text() const { return {}; }
        QIcon icon() const { return {}; }
        Qt::ItemFlags flags() const { return Qt::ItemIsEnabled; }
    };
    struct CollectionNode;
    struct BasePoolObjectNode;
    struct GroupNode : INode
    {
        std::unordered_map<QString, std::unique_ptr<amuse::AudioGroupDatabase>>::iterator m_it;
        GroupNode(const QString& name) : INode(name) {}
        GroupNode(std::unordered_map<QString, std::unique_ptr<amuse::AudioGroupDatabase>>::iterator it)
        : INode(it->first), m_it(it) {}

        int hypotheticalIndex(const QString& name) const;

        static QIcon Icon;
        Type type() const { return Type::Group; }
        QString text() const { return m_name; }
        QIcon icon() const { return Icon; }

        CollectionNode* getCollectionOfType(Type tp) const;
        amuse::AudioGroupDatabase* getAudioGroup() const { return m_it->second.get(); }
        BasePoolObjectNode* pageObjectNodeOfId(amuse::ObjectId id) const;
    };
    struct SongGroupNode : INode
    {
        amuse::GroupId m_id;
        amuse::ObjToken<amuse::SongGroupIndex> m_index;
        SongGroupNode(const QString& name, amuse::ObjToken<amuse::SongGroupIndex> index)
        : INode(name), m_index(index) {}
        SongGroupNode(amuse::GroupId id, amuse::ObjToken<amuse::SongGroupIndex> index)
        : INode(amuse::GroupId::CurNameDB->resolveNameFromId(id).data()), m_id(id), m_index(index) {}

        static QIcon Icon;
        Type type() const { return Type::SongGroup; }
        QString text() const { return m_name; }
        QIcon icon() const { return Icon; }

        void registerNames(const NameUndoRegistry& registry) const
        {
            amuse::GroupId::CurNameDB->registerPair(text().toUtf8().data(), m_id);
            for (auto& p : m_index->m_midiSetups)
                registry.registerSongName(p.first);
        }
        void unregisterNames(NameUndoRegistry& registry) const
        {
            amuse::GroupId::CurNameDB->remove(m_id);
            for (auto& p : m_index->m_midiSetups)
                registry.unregisterSongName(p.first);
        }
    };
    struct SoundGroupNode : INode
    {
        amuse::GroupId m_id;
        amuse::ObjToken<amuse::SFXGroupIndex> m_index;
        SoundGroupNode(const QString& name, amuse::ObjToken<amuse::SFXGroupIndex> index)
        : INode(name), m_index(index) {}
        SoundGroupNode(amuse::GroupId id, amuse::ObjToken<amuse::SFXGroupIndex> index)
        : INode(amuse::GroupId::CurNameDB->resolveNameFromId(id).data()), m_id(id), m_index(index) {}

        static QIcon Icon;
        Type type() const { return Type::SoundGroup; }
        QString text() const { return m_name; }
        QIcon icon() const { return Icon; }

        void registerNames(const NameUndoRegistry& registry) const
        {
            amuse::GroupId::CurNameDB->registerPair(text().toUtf8().data(), m_id);
            for (auto& p : m_index->m_sfxEntries)
                registry.registerSFXName(p.first);
        }
        void unregisterNames(NameUndoRegistry& registry) const
        {
            amuse::GroupId::CurNameDB->remove(m_id);
            for (auto& p : m_index->m_sfxEntries)
                registry.unregisterSFXName(p.first);
        }
    };
    struct CollectionNode : INode
    {
        QIcon m_icon;
        Type m_collectionType;
        CollectionNode(const QString& name, const QIcon& icon, Type collectionType)
        : INode(name), m_icon(icon), m_collectionType(collectionType) {}

        Type type() const { return Type::Collection; }
        QString text() const { return m_name; }
        QIcon icon() const { return m_icon; }
        Qt::ItemFlags flags() const { return Qt::ItemIsEnabled; }

        Type collectionType() const { return m_collectionType; }
        int indexOfId(amuse::ObjectId id) const;
        amuse::ObjectId idOfIndex(int idx) const;
        BasePoolObjectNode* nodeOfIndex(int idx) const;
        BasePoolObjectNode* nodeOfId(amuse::ObjectId id) const;
    };
    struct BasePoolObjectNode : INode
    {
        amuse::ObjectId m_id;
        BasePoolObjectNode(const QString& name) : INode(name) {}
        BasePoolObjectNode(amuse::ObjectId id, const QString& name)
        : INode(name), m_id(id) {}
        amuse::ObjectId id() const { return m_id; }
        QString text() const { return m_name; }
        QIcon icon() const { return {}; }
    };
    template <class ID, class T, INode::Type TP>
    struct PoolObjectNode : BasePoolObjectNode
    {
        amuse::ObjToken<T> m_obj;
        PoolObjectNode(const QString& name, amuse::ObjToken<T> obj) : BasePoolObjectNode(name), m_obj(obj) {}
        PoolObjectNode(ID id, amuse::ObjToken<T> obj)
        : BasePoolObjectNode(id, ID::CurNameDB->resolveNameFromId(id).data()), m_obj(obj) {}

        Type type() const { return TP; }

        void registerNames(const NameUndoRegistry& registry) const
        {
            ID::CurNameDB->registerPair(text().toUtf8().data(), m_id);
        }
        void unregisterNames(NameUndoRegistry& registry) const
        {
            ID::CurNameDB->remove(m_id);
        }
    };
    using SoundMacroNode = PoolObjectNode<amuse::SoundMacroId, amuse::SoundMacro, INode::Type::SoundMacro>;
    using ADSRNode = PoolObjectNode<amuse::TableId, std::unique_ptr<amuse::ITable>, INode::Type::ADSR>;
    using CurveNode = PoolObjectNode<amuse::TableId, std::unique_ptr<amuse::ITable>, INode::Type::Curve>;
    using KeymapNode = PoolObjectNode<amuse::KeymapId, std::array<amuse::Keymap, 128>, INode::Type::Keymap>;
    using LayersNode = PoolObjectNode<amuse::LayersId, std::vector<amuse::LayerMapping>, INode::Type::Layer>;
    using SampleNode = PoolObjectNode<amuse::SampleId, amuse::SampleEntry, INode::Type::Sample>;

    amuse::ObjToken<RootNode> m_root;

    bool m_needsReset = false;
    void _buildGroupNodeCollections(GroupNode& gn);
    void _buildGroupNode(GroupNode& gn);
    void _resetModelData();
    void _resetSongRefCount();

public:
    explicit ProjectModel(const QString& path, QObject* parent = Q_NULLPTR);

    bool clearProjectData();
    bool openGroupData(const QString& groupName, UIMessenger& messenger);
    void openSongsData();
    void importSongsData(const QString& path);
    bool reloadSampleData(const QString& groupName, UIMessenger& messenger);
    bool importGroupData(const QString& groupName, const amuse::AudioGroupData& data,
                         ImportMode mode, UIMessenger& messenger);
    void saveSongsIndex();
    bool saveToFile(UIMessenger& messenger);
    QStringList getGroupList() const;
    bool exportGroup(const QString& path, const QString& groupName, UIMessenger& messenger) const;

    bool ensureModelData();

    QModelIndex proxyCreateIndex(int arow, int acolumn, void *adata) const;
    QModelIndex index(int row, int column, const QModelIndex& parent = QModelIndex()) const;
    QModelIndex index(INode* node) const;
    QModelIndex parent(const QModelIndex& child) const;
    int rowCount(const QModelIndex& parent = QModelIndex()) const;
    int columnCount(const QModelIndex& parent = QModelIndex()) const;
    QVariant data(const QModelIndex& index, int role = Qt::DisplayRole) const;
    Qt::ItemFlags flags(const QModelIndex& index) const;
    INode* node(const QModelIndex& index) const;
    GroupNode* getGroupNode(INode* node) const;
    bool canEdit(const QModelIndex& index) const;
    RootNode* rootNode() const { return m_root.get(); }

    void _postAddNode(INode* n, const NameUndoRegistry& registry);
    void _preDelNode(INode* n, NameUndoRegistry& registry);
    void _addNode(GroupNode* node, std::unique_ptr<amuse::AudioGroupDatabase>&& data, const NameUndoRegistry& registry);
    std::unique_ptr<amuse::AudioGroupDatabase> _delNode(GroupNode* node, NameUndoRegistry& registry);
    GroupNode* newSubproject(const QString& name);
    template <class NT, class T>
    void _addGroupNode(NT* node, GroupNode* parent, const NameUndoRegistry& registry, T& container);
    template <class NT, class T>
    void _delGroupNode(NT* node, GroupNode* parent, NameUndoRegistry& registry, T& container);
    void _addNode(SoundGroupNode* node, GroupNode* parent, const NameUndoRegistry& registry);
    void _delNode(SoundGroupNode* node, GroupNode* parent, NameUndoRegistry& registry);
    SoundGroupNode* newSoundGroup(GroupNode* group, const QString& name);
    void _addNode(SongGroupNode* node, GroupNode* parent, const NameUndoRegistry& registry);
    void _delNode(SongGroupNode* node, GroupNode* parent, NameUndoRegistry& registry);
    SongGroupNode* newSongGroup(GroupNode* group, const QString& name);
    template <class NT, class T>
    void _addPoolNode(NT* node, GroupNode* parent, const NameUndoRegistry& registry, T& container);
    template <class NT, class T>
    void _delPoolNode(NT* node, GroupNode* parent, NameUndoRegistry& registry, T& container);
    void _addNode(SoundMacroNode* node, GroupNode* parent, const NameUndoRegistry& registry);
    void _delNode(SoundMacroNode* node, GroupNode* parent, NameUndoRegistry& registry);
    SoundMacroNode* newSoundMacro(GroupNode* group, const QString& name,
                                  const SoundMacroTemplateEntry* templ = nullptr);
    void _addNode(ADSRNode* node, GroupNode* parent, const NameUndoRegistry& registry);
    void _delNode(ADSRNode* node, GroupNode* parent, NameUndoRegistry& registry);
    ADSRNode* newADSR(GroupNode* group, const QString& name);
    void _addNode(CurveNode* node, GroupNode* parent, const NameUndoRegistry& registry);
    void _delNode(CurveNode* node, GroupNode* parent, NameUndoRegistry& registry);
    CurveNode* newCurve(GroupNode* group, const QString& name);
    void _addNode(KeymapNode* node, GroupNode* parent, const NameUndoRegistry& registry);
    void _delNode(KeymapNode* node, GroupNode* parent, NameUndoRegistry& registry);
    KeymapNode* newKeymap(GroupNode* group, const QString& name);
    void _addNode(LayersNode* node, GroupNode* parent, const NameUndoRegistry& registry);
    void _delNode(LayersNode* node, GroupNode* parent, NameUndoRegistry& registry);
    LayersNode* newLayers(GroupNode* group, const QString& name);
    void del(const QModelIndex& index);

    const QDir& dir() const { return m_dir; }
    QString path() const { return m_dir.path(); }
    NullItemProxyModel* getNullProxy() { return &m_nullProxy; }
    PageObjectProxyModel* getPageObjectProxy() { return &m_pageObjectProxy; }

    GroupNode* getGroupOfSfx(amuse::SFXId id) const;
    QString getMIDIPathOfSong(amuse::SongId id) const;
    void setMIDIPathOfSong(amuse::SongId id, const QString& path);
    void _allocateSongId(amuse::SongId id, std::string_view name);
    std::pair<amuse::SongId, std::string> allocateSongId();
    void deallocateSongId(amuse::SongId oldId);
    amuse::SongId exchangeSongId(amuse::SongId oldId, std::string_view newName);

    void setIdDatabases(INode* context) const;
};


#endif //AMUSE_PROJECT_MODEL_HPP