// Copyright (c) 2009 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef APP_GTK_DND_UTIL_H_
#define APP_GTK_DND_UTIL_H_

#include <gtk/gtk.h>
#include <vector>

#include "base/string16.h"

class GURL;

class GtkDndUtil {
 public:
  // Registry of all internal int codes for drag and drop.
  enum {
    // Intra-application types.
    CHROME_TAB = 1 << 0,
    CHROME_BOOKMARK_ITEM = 1 << 1,
    CHROME_WEBDROP_FILE_CONTENTS = 1 << 2,
    CHROME_NAMED_URL = 1 << 3,

    // Standard types.
    TEXT_PLAIN = 1 << 4,
    TEXT_URI_LIST = 1 << 5,
    TEXT_HTML = 1 << 6,

    INVALID_TARGET = 1 << 7,
  };

  // Get the atom for a given target (of the above enum type). Will return NULL
  // for non-custom targets, such as CHROME_TEXT_PLAIN.
  static GdkAtom GetAtomForTarget(int target);

  // Creates a target list from the given mask. The mask should be an OR of
  // CHROME_* values. The target list is returned with ref count 1; the caller
  // is responsible for unreffing it when it is no longer needed.
  // Since the MIME type for WEBDROP_FILE_CONTENTS depends on the file's
  // contents, that flag is ignored by this function. It is the responsibility
  // of the client code to do the right thing.
  static GtkTargetList* GetTargetListFromCodeMask(int code_mask);

  // Set the drag target list for |source| with the target list that
  // corresponds to |code_mask|.
  static void SetSourceTargetListFromCodeMask(GtkWidget* source, int code_mask);

  // Set the accepted targets list for |dest|. The |target_codes| array should
  // be sorted in preference order and should be terminated with -1.
  static void SetDestTargetList(GtkWidget* dest, const int* target_codes);

  // Write a URL to the selection in the given type.
  static void WriteURLWithName(GtkSelectionData* selection_data,
                               const GURL& url,
                               const string16& title,
                               int type);

  // Extracts data of type CHROME_NAMED_URL from |selection_data| into
  // |url| and |title|. Returns true if the url/title were safely extracted
  // and the url is valid.
  static bool ExtractNamedURL(GtkSelectionData* selection_data,
                              GURL* url,
                              string16* title);

  // Extracts data of type TEXT_URI_LIST from |selection_data| into |urls|.
  static bool ExtractURIList(GtkSelectionData* selection_data,
                             std::vector<GURL>* urls);

 private:
  GtkDndUtil();

  static void AddTargetToList(GtkTargetList* targets, int target_code);
};

#endif  // APP_GTK_DND_UTIL_H_