FileDialog.h

#ifndef NEO_FILEDIALOG_H
#define NEO_FILEDIALOG_H

#include <Shobjidl.h> // IFileDialog

namespace neo
{

enum FD_FLAGS_ENUM
{
    FD_FILEMUSTEXIST           = 0x00000001, //<! the return item must exist
    FD_PATHMUSTEXIST           = 0x00000002, //<! the return item must be in an existing path
    FD_FORCEFILESYSTEM         = 0x00000004, //<! only allow file system items
    FD_CREATEPROMPT            = 0x00000008, //<! prompt when choosing a nonexisting file in SaveFileDialog
    FD_OVERWRITEPROMPT         = 0x00000010, //<! prompt before overwriting a file in SaveFileDialog
    FD_STRICTFILETYPES         = 0x00000020, //<! only allow the types set by FileDialog::SetFilter()
    FD_KEEPWORKINGDIR          = 0x00000040, //<! don't change the working directory
    FD_NOVALIDATE              = 0x00000080, //<! don't check the returned item from OpenFileDialog
    FD_ALLOWMULTISELECT        = 0x00000100, //<! for OpenFileDialog
    FD_NOREADONLYRETURN        = 0x00000200, //<! don't return read only item

    /*
    FOS_ALLNONSTORAGEITEMS     = 0x00000080,
    FOS_SHAREAWARE             = 0x00004000,
    FOS_NOTESTFILECREATE       = 0x00010000,
    FOS_HIDEPINNEDPLACES       = 0x00040000,
    FOS_NODEREFERENCELINKS     = 0x00100000,
    FOS_DONTADDTORECENT        = 0x02000000,
    FOS_FORCESHOWHIDDEN        = 0x10000000,
    FOS_FORCEPREVIEWPANEON     = 0x40000000,
    FOS_SUPPORTSTREAMABLEITEMS = 0x80000000
    */
};
typedef DWORD FD_FLAGS;

class FileTypeFilter
{
public:
    FileTypeFilter& Add(const tstring& type, const tstring& description);
    size_t GetCount() const { return _filter.size(); }
    const tstring& GetType(size_t i) const { return _filter[i].first; }
    const tstring& GetDescription(size_t i) const { return _filter[i].second; }
private:
    std::vector<std::pair<tstring, tstring>> _filter;
};

class ActiveFileDialogIF
{
public:
    virtual ~ActiveFileDialogIF() {}

    virtual tstring GetResult() = 0;
    virtual std::vector<tstring> GetResults() = 0;
};

class FileDialog;

class FileDialogEvents
{
public:
    virtual ~FileDialogEvents() {}

    virtual bool OnFileOk(FileDialog* dialog, ActiveFileDialogIF* dialogImpl) { return true; }
};

class FileDialogOptions
{
public:
    enum MODE
    {
        OPEN_FILE, 
        SAVE_FILE, 
        PICK_FOLDER, 
    };

    FileDialogOptions();

    MODE _mode;
    FD_FLAGS _addedFlags;
    FD_FLAGS _removedFlags;
    FileTypeFilter _fileFilter;
    UINT _fileFilterIndex;
    tstring _filename;
    tstring _folder;
    tstring _title;
    tstring _defaultExt;
};

class FileDialog
{
public:
    FileDialog(HWND parent, FileDialogEvents* events = 0);
    virtual ~FileDialog();

    void SetIdentifier(REFGUID id);
    const GUID* GetIdentifier() const { return _identifier; }

    HWND GetParentHandle() const { return _parent; }
    FileDialogEvents* GetEvents() const { return _events; }

    int ShowModal();

    const tstring& GetResult() const { return resultFiles.front(); }

    const std::vector<tstring>& GetResults() const { return resultFiles; }

    void SetMode(FileDialogOptions::MODE mode);

    void ChangeFlags(FD_FLAGS add, FD_FLAGS remove = 0);

    void SetFilter(const FileTypeFilter& filter);
    
    void SetFilterIndex(UINT index);
    
    void SetFilename(const tstring& filename);
    
    void SetFolder(const tstring& folder);

    void SetTitle(const tstring& title);

    void SetDefaultExtension(const tstring& ext);

    const FileDialogOptions& GetOptions() const { return _options; }
protected:
    virtual void OnInitIFileDialog(IFileDialog* dialog) {}
private:
    // these are not part of FileDialogOptions because they are pointers
    HWND _parent;
    FileDialogEvents* _events;
    const GUID* _identifier;

    std::vector<tstring> resultFiles;

    FileDialogOptions _options;
};

class OpenFileDialog : public FileDialog
{
public:
    OpenFileDialog(HWND parent, FileDialogEvents* events = 0)
    : FileDialog(parent, events)
    {
        SetMode(FileDialogOptions::OPEN_FILE);
    }
};

class SaveFileDialog : public FileDialog
{
public:
    SaveFileDialog(HWND parent, FileDialogEvents* events = 0)
    : FileDialog(parent, events)
    {
        SetMode(FileDialogOptions::SAVE_FILE);
    }
};

class PickFolderDialog : public FileDialog
{
public:
    PickFolderDialog(HWND parent, FileDialogEvents* events = 0)
    : FileDialog(parent, events)
    {
        SetMode(FileDialogOptions::PICK_FOLDER);
    }
};

} // namespace neo

#endif