#include "geodesic.h"
#include "frame.h"

#include <math.h>
#include <stdio.h>

int main(void) {
  SpacetimeSource spacetime = {0};
  MetricData metric;
  ObserverState observer;
  ObserverState oriented_observer;
  ObserverState inward_observer;
  const GeodesicTraceConfig trace = {.coordinate_time_step = 0.1,
                                     .max_steps = 4096,
                                     .capture_log_alpha_p0 = 8.0};
  int result = 1;
  if (spacetime_create_schwarzschild_ks(&spacetime, 1.0, 256.0, 1.5) ||
      spacetime_eval(&spacetime, 0.0, (double[]){2.0, 0.0, 0.0}, &metric) ||
      !isfinite(metric.alpha) || !isfinite(metric.gamma[0][0]) ||
      !isfinite(metric.K[0][0]) ||
      observer_static_schwarzschild_ks(1.0, 30.0, &observer) ||
      observer_static_schwarzschild_ks_look_at(1.0, 40.0, 270.0, 30.0,
                                                &oriented_observer) ||
      fabs(oriented_observer.coordinate_position[0]) > 1e-12 ||
      fabs(oriented_observer.coordinate_position[1] - 20.0 * sqrt(3.0)) >
          1e-12 ||
      fabs(oriented_observer.coordinate_position[2] + 20.0) >
          1e-12 ||
      fabs(oriented_observer.tetrad[1][1]) > 1e-12 ||
      fabs(oriented_observer.tetrad[1][2] + sqrt(0.95) * sqrt(3.0) / 2.0) >
          1e-12 ||
      fabs(oriented_observer.tetrad[1][3] - 0.5 * sqrt(0.95)) >
          1e-12 ||
      observer_inward_schwarzschild_ks(1.0, 30.0, 0.5,
                                       &inward_observer) ||
      fabs(inward_observer.tetrad[0][0] -
           (2.0 / sqrt(3.0)) * (observer.tetrad[0][0] +
                                 0.5 * observer.tetrad[1][0])) >
          1e-12 ||
      fabs(inward_observer.tetrad[1][1] -
           (2.0 / sqrt(3.0)) * (0.5 * observer.tetrad[0][1] +
                                 observer.tetrad[1][1])) >
          1e-12 ||
      !observer_inward_schwarzschild_ks(1.0, 30.0, 1.0,
                                         &inward_observer))
    goto done;
  const RayEndpoint central = geodesic_trace_past(
      &spacetime, &observer, (double[]){1.0, 0.0, 0.0}, &trace);
  const RayEndpoint inside_shadow = geodesic_trace_past(
      &spacetime, &observer, (double[]){cos(0.10), sin(0.10), 0.0}, &trace);
  const RayEndpoint outside_shadow = geodesic_trace_past(
      &spacetime, &observer, (double[]){cos(0.30), sin(0.30), 0.0}, &trace);
  if (central.status != RAY_ENDPOINT_CAPTURED ||
      inside_shadow.status != RAY_ENDPOINT_CAPTURED ||
      outside_shadow.status != RAY_ENDPOINT_ESCAPED) {
    fprintf(stderr,
            "Schwarzschild KS shadow regression failed (center=%d, inside=%d, "
            "outside=%d)\n",
            central.status, inside_shadow.status, outside_shadow.status);
    goto done;
  }
  /* A coarse field covering the shadow must genuinely refine: its initial
   * capture/escape-discontinuous triangles are a separate trigger from the
   * smooth direction-error criterion. */
  FrameLensMesh mesh = {0};
  const RefinementConfig refinement = {.max_level = 1,
                                       .angle_absolute_rad = 1e-5,
                                       .angle_relative = 1e-5,
                                       .jacobian_minimum = 1e-3,
                                       .min_edge_pixels = 1.0,
                                       .min_area_pixels2 = 1.0};
  if (frame_lens_mesh_build_coarse(&mesh, 48, 48, 24, 40.0) ||
      frame_lens_mesh_trace(&mesh, &spacetime, &observer, &trace) ||
      frame_lens_mesh_refine(&mesh, &spacetime, &observer, &trace,
                             &refinement) ||
      mesh.vertex_count <= 9 || mesh.triangle_count <= 8) {
    fputs("Schwarzschild adaptive-refinement regression failed\n", stderr);
    frame_lens_mesh_destroy(&mesh);
    goto done;
  }
  frame_lens_mesh_destroy(&mesh);
  result = 0;
done:
  spacetime_destroy(&spacetime);
  return result;
}