#pragma region CPL License
/*
Nuclex Native Framework
Copyright (C) 2002-2013 Nuclex Development Labs

This library is free software; you can redistribute it and/or
modify it under the terms of the IBM Common Public License as
published by the IBM Corporation; either version 1.0 of the
License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
IBM Common Public License for more details.

You should have received a copy of the IBM Common Public
License along with this library
*/
#pragma endregion // CPL License

// If the library is compiled as a DLL, this ensures symbols are exported
#define NUCLEX_GRAPHICS_SOURCE 1

#include "Nuclex/Graphics/Rasterization/Texture.h"

#include <stdexcept>
#include <cassert>

namespace Nuclex { namespace Graphics { namespace Rasterization {

  // ------------------------------------------------------------------------------------------- //

  Texture::Texture(std::size_t sizeInBytes, PixelFormat::Enum pixelFormat, Usage::Enum usage) :
    SizeInBytes(sizeInBytes),
    PixelFormat(pixelFormat),
    usage(usage),
    Pixels(new std::uint8_t[sizeInBytes]) {}

  // ------------------------------------------------------------------------------------------- //

  Texture::Texture(const Texture &other) :
    SizeInBytes(other.SizeInBytes),
    PixelFormat(other.PixelFormat),
    Pixels(new std::uint8_t[other.SizeInBytes]) {
    std::copy_n(other.Pixels, this->SizeInBytes, this->Pixels);
  }

  // ------------------------------------------------------------------------------------------- //

  Texture::~Texture() {
    delete []this->Pixels;
  }

  // ------------------------------------------------------------------------------------------- //

  Texture &Texture::operator =(const Texture &other) {
    if(other.PixelFormat != this->PixelFormat) {
      throw std::runtime_error("Pixel format mismatch");
    }
    // TODO: Copy existing texture
    return *this;
  }

  // ------------------------------------------------------------------------------------------- //

  void Texture::SuppressChangeNotifications() {
    this->changedRegion.Left = static_cast<std::size_t>(-1);
    this->changedRegion.Right = 0;
    this->changedRegion.Top = static_cast<std::size_t>(-1);
    this->changedRegion.Bottom = 0;
    this->changedRegion.Front = static_cast<std::size_t>(-1);
    this->changedRegion.Back = 0;
  }

  // ------------------------------------------------------------------------------------------- //

  void Texture::PermitChangeNotifications() {
    Box changedRegion = this->changedRegion;

    this->changedRegion.Reset();

    if(!changedRegion.IsEmpty()) {
      OnChanged(changedRegion);
    }
  }

  // ------------------------------------------------------------------------------------------- //

  Texture::Observer *Texture::GetObserver(const void *owner) const {
    return this->observers.Get(owner);
  }

  // ------------------------------------------------------------------------------------------- //

  void Texture::AttachObserver(const void *owner, Observer *observer) {
    using namespace std;

    bool wasUnique = this->observers.AttachUnique(owner, observer);

    // Observer management should be accurate and error-free!
    assert(wasUnique && "Only one observer can be attached per owner");
    wasUnique; // avoid unreferenced parameter warning
  }

  // ------------------------------------------------------------------------------------------- //

  void Texture::DetachObserver(const void *owner) {
    using namespace std;

    bool wasAttached = this->observers.Detach(owner);

    // Observer management should be accurate and error-free!
    assert(wasAttached && "Attempted to detach an observer that was not attached");
    wasAttached; // avoid unreferenced parameter warning
  }

  // ------------------------------------------------------------------------------------------- //

  void Texture::OnDestroying() {
    std::vector<Observer *> copy = this->observers.Copy();
    for(std::size_t index = 0; index < copy.size(); ++index) {
      copy[index]->Destroying();
    }
  }

  // ------------------------------------------------------------------------------------------- //

  void Texture::OnCleared() {
    std::vector<Observer *> copy = this->observers.Copy();
    for(std::size_t index = 0; index < copy.size(); ++index) {
      copy[index]->Cleared();
    }
  }

  // ------------------------------------------------------------------------------------------- //

  void Texture::OnChanged(const Box &changedRegion) {
    if(this->changedRegion.IsEmpty()) {
      std::vector<Observer *> copy = this->observers.Copy();
      for(std::size_t index = 0; index < copy.size(); ++index) {
        copy[index]->Changed(changedRegion);
      }
    } else { // Change notifications are currently suppressed
      this->changedRegion.Merge(changedRegion);
    }
  }

  // ------------------------------------------------------------------------------------------- //

}}} // namespace Nuclex::Graphics::Rasterization