/// @file
/// Test integration with a 2D Simplex non-tensor H1 basis
/// \test Test integration with a 2D Simplex non-tensor H1 basis
#include <ceed.h>
#include <math.h>

#include "t320-basis.h"

// polynomial eval helper
static CeedScalar feval(CeedScalar x1, CeedScalar x2) { return x1 * x1 + x2 * x2 + x1 * x2 + 1; }

// main test
int main(int argc, char **argv) {
  Ceed              ceed;
  CeedVector        In, Out, Weights;
  const CeedInt     P = 6, Q = 4, dim = 2;
  CeedBasis         b;
  CeedScalar        q_ref[dim * Q], q_weight[Q];
  CeedScalar        interp[P * Q], grad[dim * P * Q];
  CeedScalar        xr[] = {0., 0.5, 1., 0., 0.5, 0., 0., 0., 0., 0.5, 0.5, 1.};
  const CeedScalar *out, *weights;
  CeedScalar        in[P], sum;

  buildmats(q_ref, q_weight, interp, grad);

  CeedInit(argv[1], &ceed);

  CeedBasisCreateH1(ceed, CEED_TOPOLOGY_TRIANGLE, 1, P, Q, interp, grad, q_ref, q_weight, &b);

  // Interpolate function to quadrature points
  for (int i = 0; i < P; i++) in[i] = feval(xr[0 * P + i], xr[1 * P + i]);

  CeedVectorCreate(ceed, P, &In);
  CeedVectorSetArray(In, CEED_MEM_HOST, CEED_USE_POINTER, in);
  CeedVectorCreate(ceed, Q, &Out);
  CeedVectorSetValue(Out, 0);
  CeedVectorCreate(ceed, Q, &Weights);
  CeedVectorSetValue(Weights, 0);

  CeedBasisApply(b, 1, CEED_NOTRANSPOSE, CEED_EVAL_INTERP, In, Out);
  CeedBasisApply(b, 1, CEED_NOTRANSPOSE, CEED_EVAL_WEIGHT, CEED_VECTOR_NONE, Weights);

  // Check values at quadrature points
  CeedVectorGetArrayRead(Out, CEED_MEM_HOST, &out);
  CeedVectorGetArrayRead(Weights, CEED_MEM_HOST, &weights);
  sum = 0;
  for (int i = 0; i < Q; i++) sum += out[i] * weights[i];
  if (fabs(sum - 17. / 24.) > 100. * CEED_EPSILON) printf("%f != %f\n", sum, 17. / 24.);
  CeedVectorRestoreArrayRead(Out, &out);
  CeedVectorRestoreArrayRead(Weights, &weights);

  CeedVectorDestroy(&In);
  CeedVectorDestroy(&Out);
  CeedVectorDestroy(&Weights);
  CeedBasisDestroy(&b);
  CeedDestroy(&ceed);
  return 0;
}