/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* 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 WEBGL_MEMORY_TRACKER_H_
#define WEBGL_MEMORY_TRACKER_H_

#include "mozilla/StaticPtr.h"
#include "nsIMemoryReporter.h"

namespace mozilla {

class WebGLContext;

class WebGLMemoryTracker : public nsIMemoryReporter {
  NS_DECL_THREADSAFE_ISUPPORTS
  NS_DECL_NSIMEMORYREPORTER

  WebGLMemoryTracker();
  static StaticRefPtr<WebGLMemoryTracker> sUniqueInstance;

  // Here we store plain pointers, not RefPtrs: we don't want the
  // WebGLMemoryTracker unique instance to keep alive all
  // WebGLContexts ever created.
  typedef nsTArray<const WebGLContext*> ContextsArrayType;
  ContextsArrayType mContexts;

  void InitMemoryReporter();

  static WebGLMemoryTracker* UniqueInstance();

  static ContextsArrayType& Contexts() { return UniqueInstance()->mContexts; }

  friend class WebGLContext;

 public:
  static void AddWebGLContext(const WebGLContext* c) {
    Contexts().AppendElement(c);
  }

  static void RemoveWebGLContext(const WebGLContext* c) {
    ContextsArrayType& contexts = Contexts();
    contexts.RemoveElement(c);
    if (contexts.IsEmpty()) {
      sUniqueInstance = nullptr;
    }
  }

 private:
  virtual ~WebGLMemoryTracker();

  static int64_t GetTextureMemoryUsed();

  static int64_t GetTextureCount();

  static int64_t GetBufferMemoryUsed();

  static int64_t GetBufferCacheMemoryUsed();

  static int64_t GetBufferCount();

  static int64_t GetRenderbufferMemoryUsed();

  static int64_t GetRenderbufferCount();

  static int64_t GetShaderSize();

  static int64_t GetShaderCount();

  static int64_t GetContextCount() { return Contexts().Length(); }
};

}  // namespace mozilla

#endif  // WEBGL_MEMORY_TRACKER_H_