/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef nsTreeImageListener_h_
#define nsTreeImageListener_h_

#include "nsCOMPtr.h"
#include "nsString.h"
#include "nsTreeBodyFrame.h"

class nsTreeColumn;

// This class handles image load observation.
class nsTreeImageListener final : public imgINotificationObserver {
 public:
  explicit nsTreeImageListener(nsTreeBodyFrame* aTreeFrame);

  NS_DECL_ISUPPORTS
  NS_DECL_IMGINOTIFICATIONOBSERVER

  void ClearFrame() { mTreeFrame = nullptr; }

  friend class nsTreeBodyFrame;

 protected:
  ~nsTreeImageListener();

  void UnsuppressInvalidation() { mInvalidationSuppressed = false; }
  void Invalidate();
  void AddCell(int32_t aIndex, nsTreeColumn* aCol);

 private:
  nsTreeBodyFrame* mTreeFrame;

  // A guard that prevents us from recursive painting.
  bool mInvalidationSuppressed;

  class InvalidationArea {
   public:
    explicit InvalidationArea(nsTreeColumn* aCol);
    ~InvalidationArea() { delete mNext; }

    friend class nsTreeImageListener;

   protected:
    void AddRow(int32_t aIndex);
    nsTreeColumn* GetCol() { return mCol.get(); }
    int32_t GetMin() { return mMin; }
    int32_t GetMax() { return mMax; }
    InvalidationArea* GetNext() { return mNext; }
    void SetNext(InvalidationArea* aNext) { mNext = aNext; }

   private:
    RefPtr<nsTreeColumn> mCol;
    int32_t mMin;
    int32_t mMax;
    InvalidationArea* mNext;
  };

  InvalidationArea* mInvalidationArea;
};

#endif  // nsTreeImageListener_h_