#include <vtkCPDataDescription.h>
#include <vtkCPInputDataDescription.h>
#include <vtkCPPipeline.h>
#include <vtkCPProcessor.h>
#include <vtkObjectFactory.h>
#include <vtkSmartPointer.h>

namespace
{
class vtkCPTestPipeline : public vtkCPPipeline
{
public:
  vtkTypeMacro(vtkCPTestPipeline, vtkCPPipeline);
  static vtkCPTestPipeline* New();

  virtual int RequestDataDescription(vtkCPDataDescription* dataDescription) override
  {
    return this->ShouldOutput(dataDescription);
  }

  /// Execute the pipeline. Returns 1 for success and 0 for failure.
  virtual int CoProcess(vtkCPDataDescription* dataDescription) override
  {
    this->OutputCounter++;
    if (this->ShouldOutput(dataDescription) == 0)
    {
      vtkErrorMacro("Calling CoProcess but shouldn't be.");
      return 0;
    }
    return 1;
  }

  void SetParameters(int firstInputFrequency, int secondInputFrequency, int expectedOutputCounter)
  {
    this->FirstInputFrequency = firstInputFrequency;
    this->SecondInputFrequency = secondInputFrequency;
    this->ExpectedOutputCounter = expectedOutputCounter;
  }

protected:
  vtkCPTestPipeline()
  {
    this->OutputCounter = 0;
    this->FirstInputFrequency = -1;
    this->SecondInputFrequency = -1;
    this->ExpectedOutputCounter = -1;
  }
  virtual ~vtkCPTestPipeline()
  {
    // check that we've outputted the proper amount of times
    if (this->OutputCounter != this->ExpectedOutputCounter)
    {
      vtkErrorMacro("CoProcessingTestOutputs.cxx: number of outputs was "
        << this->OutputCounter << " but the number should have been "
        << this->ExpectedOutputCounter);
    }
  }
  // We have two input data sets and we have an frequency for
  // each one of them.
  int FirstInputFrequency;
  int SecondInputFrequency;
  // We keep track of how many times we've outputted and compare that to
  // the expected number of times to verify things are working properly.
  int ExpectedOutputCounter;
  int OutputCounter;

  // This method determines if we should output or not.
  int ShouldOutput(vtkCPDataDescription* dataDescription)
  {
    vtkIdType timeStep = dataDescription->GetTimeStep();
    int retVal = 0;
    if (timeStep % this->FirstInputFrequency == 0 || dataDescription->GetForceOutput() == true)
    {
      vtkCPInputDataDescription* inputDescription =
        dataDescription->GetInputDescriptionByName("firstinput");
      inputDescription->AllFieldsOn();
      inputDescription->GenerateMeshOn();
      retVal = 1;
    }
    if (timeStep % this->SecondInputFrequency == 0 || dataDescription->GetForceOutput() == true)
    {
      vtkCPInputDataDescription* inputDescription =
        dataDescription->GetInputDescriptionByName("secondinput");
      inputDescription->AllFieldsOn();
      inputDescription->GenerateMeshOn();
      retVal = 1;
    }
    return retVal;
  }

private:
  vtkCPTestPipeline(const vtkCPTestPipeline&) = delete;
  void operator=(const vtkCPTestPipeline&) = delete;
};

vtkStandardNewMacro(vtkCPTestPipeline);
}

int CoProcessingTestOutputs(int, char* [])
{
  vtkSmartPointer<vtkCPProcessor> processor = vtkSmartPointer<vtkCPProcessor>::New();
  processor->Initialize();

  vtkSmartPointer<vtkCPTestPipeline> pipeline1 = vtkSmartPointer<vtkCPTestPipeline>::New();
  processor->AddPipeline(pipeline1);
  pipeline1->SetParameters(2, 3, 21);

  vtkSmartPointer<vtkCPTestPipeline> pipeline2 = vtkSmartPointer<vtkCPTestPipeline>::New();
  processor->AddPipeline(pipeline2);
  pipeline2->SetParameters(5, 7, 12);

  if (processor->GetNumberOfPipelines() != 2)
  {
    vtkGenericWarningMacro("Wrong number of pipelines");
    return 1;
  }

  vtkIdType numberOfTimeSteps = 30;
  for (vtkIdType timeStep = 0; timeStep < numberOfTimeSteps; timeStep++)
  {
    // use a time step length of 0.1
    double time = timeStep * 0.1;
    vtkSmartPointer<vtkCPDataDescription> dataDescription =
      vtkSmartPointer<vtkCPDataDescription>::New();
    dataDescription->AddInput("firstinput");
    dataDescription->AddInput("secondinput");
    dataDescription->SetTimeData(time, timeStep);
    if (timeStep % 11 == 0)
    {
      dataDescription->ForceOutputOn();
    }
    if (processor->RequestDataDescription(dataDescription))
    {
      if (processor->CoProcess(dataDescription) == 0)
      {
        vtkGenericWarningMacro("Co-processing problem.");
        return 1;
      }
    }
  }

  processor->Finalize();

  return 0;
}
