/*************************************************************************
 * Copyright (C) 2010-2011 Tavian Barnes <tavianator@tavianator.com>     *
 *                                                                       *
 * This file is part of The Dimension Android Binding.                   *
 *                                                                       *
 * The Dimension Android Binding is free software; you can redistribute  *
 * it and/or modify it under the terms of the GNU General Public License *
 * as published by the Free Software Foundation; either version 3 of the *
 * License, or (at your option) any later version.                       *
 *                                                                       *
 * The Dimension Android Binding 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 GNU General Public License for more details.                      *
 *                                                                       *
 * You should have received a copy of the GNU General Public License     *
 * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
 *************************************************************************/

/**
 * @file
 * Java interface to libdimension used by Android.
 */

#include "dimension-internal.h"
#include <jni.h>
#include <android/log.h>
#include <stdint.h>
#include <limits.h>

#define TAG "libdimension_jni"

static void
dmnsn_test_scene_set_defaults(dmnsn_scene *scene)
{
  /* Default texture */
  scene->default_texture->pigment =
    dmnsn_new_solid_pigment(DMNSN_TCOLOR(dmnsn_black));
  dmnsn_finish *default_finish = &scene->default_texture->finish;
  default_finish->ambient = dmnsn_new_ambient(
    dmnsn_color_from_sRGB(dmnsn_color_mul(0.1, dmnsn_white))
  );
  default_finish->diffuse = dmnsn_new_lambertian(dmnsn_sRGB_inverse_gamma(0.7));
}

static void
dmnsn_test_scene_add_canvas(dmnsn_scene *scene, size_t width, size_t height)
{
  scene->canvas = dmnsn_new_canvas(width, height);
}

static void
dmnsn_test_scene_add_camera(dmnsn_scene *scene)
{
  /* Set up the transformation matrix for the perspective camera */
  dmnsn_matrix trans = dmnsn_scale_matrix(
    dmnsn_new_vector(
      ((double)scene->canvas->width)/scene->canvas->height, 1.0, 1.0
    )
  );
  trans = dmnsn_matrix_mul(
    dmnsn_rotation_matrix(dmnsn_new_vector(0.0624188099959577, 0.0, 0.0)),
    trans
  );
  trans = dmnsn_matrix_mul(
    dmnsn_translation_matrix(dmnsn_new_vector(0.0, 0.25, -4.0)),
    trans
  );
  trans = dmnsn_matrix_mul(
    dmnsn_rotation_matrix(dmnsn_new_vector(0.0, dmnsn_radians(53.0), 0.0)),
    trans
  );

  /* Create a perspective camera */
  scene->camera = dmnsn_new_perspective_camera();
  scene->camera->trans = trans;
}

static void
dmnsn_test_scene_add_background(dmnsn_scene *scene)
{
  scene->background = dmnsn_new_solid_pigment(dmnsn_clear);
}

static void
dmnsn_test_scene_add_lights(dmnsn_scene *scene)
{
  dmnsn_light *light = dmnsn_new_point_light(
    dmnsn_new_vector(-15.0, 20.0, 10.0),
    dmnsn_white
  );
  dmnsn_array_push(scene->lights, &light);
}

static void
dmnsn_test_scene_add_hollow_cube(dmnsn_scene *scene)
{
  dmnsn_object *cube = dmnsn_new_cube();
  cube->trans = dmnsn_rotation_matrix(
    dmnsn_new_vector(dmnsn_radians(45.0), 0.0, 0.0)
  );

  cube->texture = dmnsn_new_texture();
  dmnsn_tcolor cube_color = dmnsn_new_tcolor(dmnsn_blue, 0.75, 1.0/3.0);
  cube->texture->pigment = dmnsn_new_solid_pigment(cube_color);

  dmnsn_color reflect =
    dmnsn_color_from_sRGB(dmnsn_color_mul(0.5, dmnsn_white));
  cube->texture->finish.reflection =
    dmnsn_new_basic_reflection(dmnsn_black, reflect, 1.0);

  cube->interior = dmnsn_new_interior();
  cube->interior->ior = 1.1;

  dmnsn_object *sphere = dmnsn_new_sphere();
  sphere->texture = dmnsn_new_texture();
  sphere->texture->pigment = dmnsn_new_solid_pigment(DMNSN_TCOLOR(dmnsn_green));
  sphere->texture->finish.specular =
    dmnsn_new_phong(dmnsn_sRGB_inverse_gamma(0.2), 40.0);
  sphere->trans = dmnsn_scale_matrix(dmnsn_new_vector(1.25, 1.25, 1.25));

  dmnsn_object *hollow_cube = dmnsn_new_csg_difference(cube, sphere);
  dmnsn_array_push(scene->objects, &hollow_cube);
}

#define dmnsn_pigment_map_add_color(map, n, color)              \
  do {                                                          \
    dmnsn_tcolor tcolor = DMNSN_TCOLOR(color);                  \
    dmnsn_pigment *pigment = dmnsn_new_solid_pigment(tcolor);   \
    dmnsn_map_add_entry(map, n, &pigment);                      \
  } while (0)

static void
dmnsn_test_scene_add_spike(dmnsn_scene *scene)
{
  dmnsn_array *arrow_array = dmnsn_new_array(sizeof(dmnsn_object *));

  dmnsn_object *cylinder = dmnsn_new_cone(0.1, 0.1, false);
  cylinder->trans = dmnsn_scale_matrix(dmnsn_new_vector(1.0, 1.25, 1.0));
  dmnsn_array_push(arrow_array, &cylinder);

  dmnsn_object *cone = dmnsn_new_cone(0.1, 0.0, true);
  cone->trans = dmnsn_matrix_mul(
    dmnsn_translation_matrix(dmnsn_new_vector(0.0, 1.375, 0.0)),
    dmnsn_scale_matrix(dmnsn_new_vector(1.0, 0.125, 1.0))
  );
  dmnsn_array_push(arrow_array, &cone);

  dmnsn_object *arrow = dmnsn_new_csg_union(arrow_array);
  dmnsn_delete_array(arrow_array);
  dmnsn_pattern *gradient = dmnsn_new_gradient_pattern(dmnsn_y);
  dmnsn_map *gradient_pigment_map = dmnsn_new_pigment_map();
  dmnsn_pigment_map_add_color(gradient_pigment_map, 0.0,     dmnsn_red);
  dmnsn_pigment_map_add_color(gradient_pigment_map, 1.0/6.0, dmnsn_orange);
  dmnsn_pigment_map_add_color(gradient_pigment_map, 2.0/6.0, dmnsn_yellow);
  dmnsn_pigment_map_add_color(gradient_pigment_map, 3.0/6.0, dmnsn_green);
  dmnsn_pigment_map_add_color(gradient_pigment_map, 4.0/6.0, dmnsn_blue);
  dmnsn_pigment_map_add_color(gradient_pigment_map, 5.0/6.0, dmnsn_magenta);
  dmnsn_pigment_map_add_color(gradient_pigment_map, 1.0,     dmnsn_red);
  arrow->texture = dmnsn_new_texture();
  arrow->texture->pigment =
    dmnsn_new_pigment_map_pigment(gradient, gradient_pigment_map,
                                  DMNSN_PIGMENT_MAP_SRGB);

  arrow->texture->trans =
    dmnsn_matrix_mul(
      dmnsn_translation_matrix(dmnsn_new_vector(0.0, -1.25, 0.0)),
      dmnsn_scale_matrix(dmnsn_new_vector(1.0, 2.75, 1.0))
    );

  dmnsn_array *torus_array = dmnsn_new_array(sizeof(dmnsn_object *));

  dmnsn_object *torus1 = dmnsn_new_torus(0.15, 0.05);
  torus1->trans = dmnsn_translation_matrix(dmnsn_new_vector(0.0, -1.0, 0.0));
  dmnsn_array_push(torus_array, &torus1);

  dmnsn_object *torus2 = dmnsn_new_torus(0.15, 0.05);
  dmnsn_array_push(torus_array, &torus2);

  dmnsn_object *torus3 = dmnsn_new_torus(0.15, 0.05);
  torus3->trans = dmnsn_translation_matrix(dmnsn_new_vector(0.0, 1.0, 0.0));
  dmnsn_array_push(torus_array, &torus3);

  dmnsn_object *torii = dmnsn_new_csg_union(torus_array);
  dmnsn_delete_array(torus_array);
  torii->texture = dmnsn_new_texture();
  torii->texture->pigment = dmnsn_new_solid_pigment(DMNSN_TCOLOR(dmnsn_blue));
  torii->texture->finish.ambient = dmnsn_new_ambient(dmnsn_white);

  dmnsn_array *spike_array = dmnsn_new_array(sizeof(dmnsn_object *));
  dmnsn_array_push(spike_array, &arrow);
  dmnsn_array_push(spike_array, &torii);
  dmnsn_object *spike = dmnsn_new_csg_union(spike_array);
  dmnsn_delete_array(spike_array);
  spike->trans = dmnsn_rotation_matrix(
    dmnsn_new_vector(dmnsn_radians(-45.0), 0.0, 0.0)
  );
  dmnsn_array_push(scene->objects, &spike);
}

static void
dmnsn_test_scene_add_triangle_strip(dmnsn_scene *scene)
{
  dmnsn_array *strip_array = dmnsn_new_array(sizeof(dmnsn_object *));
  dmnsn_vector a = dmnsn_zero;
  dmnsn_vector b = dmnsn_new_vector(0.0, sqrt(3.0)/2.0, 0.5);
  dmnsn_vector c = dmnsn_z;
  dmnsn_texture *strip_textures[3] = {
    dmnsn_new_texture(),
    dmnsn_new_texture(),
    dmnsn_new_texture(),
  };
  strip_textures[0]->pigment =
    dmnsn_new_solid_pigment(DMNSN_TCOLOR(dmnsn_red));
  strip_textures[1]->pigment =
    dmnsn_new_solid_pigment(DMNSN_TCOLOR(dmnsn_orange));
  strip_textures[2]->pigment =
    dmnsn_new_solid_pigment(DMNSN_TCOLOR(dmnsn_yellow));
  for (unsigned int i = 0; i < 128; ++i) {
    dmnsn_object *triangle = dmnsn_new_flat_triangle(a, b, c);
    triangle->texture = strip_textures[i%3];
    DMNSN_INCREF(triangle->texture);
    dmnsn_array_push(strip_array, &triangle);

    a = b;
    b = c;
    c = dmnsn_vector_add(a, dmnsn_z);
  }
  for (unsigned int i = 0; i < 3; ++i) {
    dmnsn_delete_texture(strip_textures[i]);
  }

  dmnsn_object *strip = dmnsn_new_csg_union(strip_array);
  dmnsn_delete_array(strip_array);
  strip->trans = dmnsn_translation_matrix(dmnsn_new_vector(5.0, -2.0, -4.0));
  dmnsn_array_push(scene->objects, &strip);
}

static void
dmnsn_test_scene_add_ground(dmnsn_scene *scene)
{
  dmnsn_object *plane = dmnsn_new_plane(dmnsn_new_vector(0.0, 1.0, 0.0));
  plane->trans = dmnsn_translation_matrix(dmnsn_new_vector(0.0, -2.0, 0.0));
  dmnsn_pattern *checker1 = dmnsn_new_checker_pattern();
  dmnsn_pattern *checker2 = dmnsn_new_checker_pattern();
  dmnsn_map *small_map = dmnsn_new_pigment_map();
  dmnsn_pigment_map_add_color(small_map, 0.0, dmnsn_black);
  dmnsn_pigment_map_add_color(small_map, 1.0, dmnsn_white);
  dmnsn_pigment *small_pigment =
    dmnsn_new_pigment_map_pigment(checker1, small_map,
                                  DMNSN_PIGMENT_MAP_REGULAR);
  small_pigment->trans =
    dmnsn_scale_matrix(dmnsn_new_vector(1.0/3.0, 1.0/3.0, 1.0/3.0));
  dmnsn_map *big_map = dmnsn_new_pigment_map();
  dmnsn_pigment_map_add_color(big_map, 0.0, dmnsn_white);
  dmnsn_map_add_entry(big_map, 1.0, &small_pigment);
  plane->texture = dmnsn_new_texture();
  plane->texture->pigment =
    dmnsn_new_pigment_map_pigment(checker2, big_map, DMNSN_PIGMENT_MAP_REGULAR);
  plane->texture->pigment->quick_color = DMNSN_TCOLOR(
    dmnsn_color_from_sRGB(
      dmnsn_new_color(1.0, 0.5, 0.75)
    )
  );
  dmnsn_array_push(scene->objects, &plane);
}

static void
dmnsn_test_scene_add_objects(dmnsn_scene *scene)
{
  dmnsn_test_scene_add_hollow_cube(scene);
  dmnsn_test_scene_add_spike(scene);
  dmnsn_test_scene_add_triangle_strip(scene);
  dmnsn_test_scene_add_ground(scene);
}

/*
 * Test scene
 */
static dmnsn_scene *
dmnsn_new_test_scene(size_t width, size_t height)
{
  dmnsn_scene *scene = dmnsn_new_scene();
  dmnsn_test_scene_set_defaults(scene);
  dmnsn_test_scene_add_canvas(scene, width, height);
  dmnsn_test_scene_add_camera(scene);
  dmnsn_test_scene_add_background(scene);
  dmnsn_test_scene_add_lights(scene);
  dmnsn_test_scene_add_objects(scene);
  return scene;
}

static JavaVM *jvm;
static jobject shared_obj;
static jclass shared_cls;
static jmethodID method;

static dmnsn_scene *scene;
static dmnsn_future *future;

static pthread_key_t dmnsn_detach;
static pthread_once_t dmnsn_detach_once = PTHREAD_ONCE_INIT;

static void dmnsn_jni_optimizer_fn(const dmnsn_canvas *canvas,
                                   dmnsn_canvas_optimizer optimizer,
                                   size_t x, size_t y);

JNIEXPORT void JNICALL Java_com_tavianator_dimension_android_RaytracedView_renderNative(JNIEnv *env, jobject obj, jint width, jint height)
{
  scene = dmnsn_new_test_scene(width, height);

  (*env)->GetJavaVM(env, &jvm);
  shared_obj = (*env)->NewGlobalRef(env, obj);
  jclass cls = (*env)->GetObjectClass(env, shared_obj);
  shared_cls = (*env)->NewGlobalRef(env, cls);
  method = (*env)->GetMethodID(env, shared_cls, "setPixel", "(III)V");

  /* Use a canvas optimizer to pass pixels back to the JVM */
  dmnsn_canvas_optimizer optimizer;
  optimizer.optimizer_fn = dmnsn_jni_optimizer_fn;
  optimizer.free_fn = NULL;
  dmnsn_canvas_optimize(scene->canvas, optimizer);

  __android_log_print(ANDROID_LOG_INFO, TAG, "Rendering with %u threads ...", scene->nthreads);
  future = dmnsn_ray_trace_async(scene);
}

JNIEXPORT void JNICALL Java_com_tavianator_dimension_android_RaytracedView_waitNative(JNIEnv *env, jobject obj, jdouble progress)
{
  dmnsn_future_wait(future, progress);
}

JNIEXPORT void JNICALL Java_com_tavianator_dimension_android_RaytracedView_joinNative(JNIEnv *env, jobject obj)
{
  dmnsn_future_join(future);
  __android_log_print(ANDROID_LOG_INFO, TAG, "Rendered!");

  dmnsn_delete_scene(scene);

  (*env)->DeleteGlobalRef(env, shared_cls);
  (*env)->DeleteGlobalRef(env, shared_obj);
}

static void
dmnsn_do_detach(void *ptr)
{
  (*jvm)->DetachCurrentThread(jvm);
}

static void
dmnsn_initialize_detach(void)
{
  dmnsn_key_create(&dmnsn_detach, dmnsn_do_detach);
}

static void
dmnsn_jni_optimizer_fn(const dmnsn_canvas *canvas,
                       dmnsn_canvas_optimizer optimizer, size_t x, size_t y)
{
  dmnsn_tcolor tcolor = dmnsn_canvas_get_pixel(canvas, x, y);
  tcolor = dmnsn_tcolor_remove_filter(tcolor);
  tcolor.c = dmnsn_color_to_sRGB(tcolor.c);
  tcolor = dmnsn_tcolor_saturate(tcolor);

  uint32_t argb = 0;

  unsigned char component = (unsigned char) ((1.0 - tcolor.T)*UCHAR_MAX);
  argb |= component << UINT32_C(24);

  component = (unsigned char) (tcolor.c.R*UCHAR_MAX);
  argb |= component << UINT32_C(16);

  component = (unsigned char) (tcolor.c.G*UCHAR_MAX);
  argb |= component << UINT32_C(8);

  component = (unsigned char) (tcolor.c.B*UCHAR_MAX);
  argb |= component;

  dmnsn_once(&dmnsn_detach_once, dmnsn_initialize_detach);
  JNIEnv *env = pthread_getspecific(dmnsn_detach);
  if (env == NULL) {
    (*jvm)->AttachCurrentThread(jvm, &env, NULL);
    pthread_setspecific(dmnsn_detach, env);
  }
  (*env)->CallVoidMethod(env, shared_obj, method, (jint) x, (jint) y, (jint) argb);
}