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chenyc

2025-06-12 7b72ac13a83764a662159d4a49b7fffb90476ecb

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#include "Backend.h"
#include <string>
 
Backend::Backend(std::string name, int width, int height)
  : name(name)
  , width(width)
  , height(height)
{}
 
Backend::~Backend()
{
  this->destroySurface();
}
 
void Backend::init(const Nan::FunctionCallbackInfo<v8::Value> &info) {
  int width  = 0;
  int height = 0;
  if (info[0]->IsNumber()) width  = Nan::To<uint32_t>(info[0]).FromMaybe(0);
  if (info[1]->IsNumber()) height = Nan::To<uint32_t>(info[1]).FromMaybe(0);
 
  Backend *backend = construct(width, height);
 
  backend->Wrap(info.This());
  info.GetReturnValue().Set(info.This());
}
 
void Backend::setCanvas(Canvas* _canvas)
{
  this->canvas = _canvas;
}
 
 
cairo_surface_t* Backend::recreateSurface()
{
  this->destroySurface();
 
  return this->createSurface();
}
 
DLL_PUBLIC cairo_surface_t* Backend::getSurface() {
  if (!surface) createSurface();
  return surface;
}
 
void Backend::destroySurface()
{
  if(this->surface)
  {
    cairo_surface_destroy(this->surface);
    this->surface = NULL;
  }
}
 
 
std::string Backend::getName()
{
  return name;
}
 
int Backend::getWidth()
{
  return this->width;
}
void Backend::setWidth(int width_)
{
  this->width = width_;
  this->recreateSurface();
}
 
int Backend::getHeight()
{
  return this->height;
}
void Backend::setHeight(int height_)
{
  this->height = height_;
  this->recreateSurface();
}
 
bool Backend::isSurfaceValid(){
  bool hadSurface = surface != NULL;
  bool isValid = true;
 
  cairo_status_t status = cairo_surface_status(getSurface());
 
  if (status != CAIRO_STATUS_SUCCESS) {
    error = cairo_status_to_string(status);
    isValid = false;
  }
 
  if (!hadSurface)
    destroySurface();
 
  return isValid;
}
 
 
BackendOperationNotAvailable::BackendOperationNotAvailable(Backend* backend,
  std::string operation_name)
  : backend(backend)
  , operation_name(operation_name)
{
  msg = "operation " + operation_name +
    " not supported by backend " + backend->getName();
};
 
BackendOperationNotAvailable::~BackendOperationNotAvailable() throw() {};
 
const char* BackendOperationNotAvailable::what() const throw()
{
  return msg.c_str();
};