/* SPDX-FileCopyrightText: 2019 Blender Authors
 *
 * SPDX-License-Identifier: GPL-2.0-or-later */

/** \file
 * \ingroup editors
 */

#pragma once

#include "BLI_linklist.h"
#include "BLI_set.hh"
#include "BLI_threads.h"

#include "DNA_lineart_types.h"
#include "DNA_listBase.h"

#include <math.h>
#include <string.h>

namespace blender {

struct LineartBoundingArea;
struct LineartEdge;
struct LineartData;
struct LineartStaticMemPool;
struct LineartStaticMemPoolNode;
struct LineartElementLinkNode;
struct GreasePencilLineartModifierData;

void *lineart_list_append_pointer_pool(ListBase *h, struct LineartStaticMemPool *smp, void *data);
void *lineart_list_append_pointer_pool_sized(ListBase *h,
                                             struct LineartStaticMemPool *smp,
                                             void *data,
                                             int size);
void *lineart_list_append_pointer_pool_thread(ListBase *h,
                                              struct LineartStaticMemPool *smp,
                                              void *data);
void *lineart_list_append_pointer_pool_sized_thread(ListBase *h,
                                                    LineartStaticMemPool *smp,
                                                    void *data,
                                                    int size);
void *list_push_pointer_static(ListBase *h, struct LineartStaticMemPool *smp, void *p);
void *list_push_pointer_static_sized(ListBase *h,
                                     struct LineartStaticMemPool *smp,
                                     void *p,
                                     int size);

void *lineart_list_pop_pointer_no_free(ListBase *h);
void lineart_list_remove_pointer_item_no_free(ListBase *h, LinkData *lip);

struct LineartStaticMemPoolNode *lineart_mem_new_static_pool(struct LineartStaticMemPool *smp,
                                                             size_t size);
void *lineart_mem_acquire(struct LineartStaticMemPool *smp, size_t size);
void *lineart_mem_acquire_thread(struct LineartStaticMemPool *smp, size_t size);
void lineart_mem_destroy(struct LineartStaticMemPool *smp);

void lineart_prepend_pool(LinkNode **first, struct LineartStaticMemPool *smp, void *link);

void lineart_matrix_ortho_44d(double (*mProjection)[4],
                              double xMin,
                              double xMax,
                              double yMin,
                              double yMax,
                              double zMin,
                              double zMax);
void lineart_matrix_perspective_44d(
    double (*mProjection)[4], double fFov_rad, double fAspect, double zMin, double zMax);

int lineart_count_intersection_segment_count(struct LineartData *ld);

void lineart_count_and_print_render_buffer_memory(struct LineartData *ld);

#define LRT_ITER_ALL_LINES_BEGIN \
  { \
    LineartEdge *e; \
    for (int _i = 0; _i < ld->pending_edges.next; _i++) { \
      e = ld->pending_edges.array[_i];

#define LRT_ITER_ALL_LINES_NEXT ; /* Doesn't do anything now with new array setup. */

#define LRT_ITER_ALL_LINES_END \
  LRT_ITER_ALL_LINES_NEXT \
  } \
  }

#define LRT_BOUND_AREA_CROSSES(b1, b2) \
  ((b1)[0] < (b2)[1] && (b1)[1] > (b2)[0] && (b1)[3] < (b2)[2] && (b1)[2] > (b2)[3])

/* Initial bounding area row/column count, setting 10 is tested to be relatively optimal for the
 * performance under current algorithm. */
#define LRT_BA_ROWS 10

#define LRT_EDGE_BA_MARCHING_BEGIN(fb1, fb2) \
  double x = fb1[0], y = fb1[1]; \
  LineartBoundingArea *ba = lineart_edge_first_bounding_area(ld, fb1, fb2); \
  LineartBoundingArea *nba = ba; \
  double k = (fb2[1] - fb1[1]) / (fb2[0] - fb1[0] + 1e-30); \
  int positive_x = (fb2[0] - fb1[0]) > 0 ? 1 : (fb2[0] == fb1[0] ? 0 : -1); \
  int positive_y = (fb2[1] - fb1[1]) > 0 ? 1 : (fb2[1] == fb1[1] ? 0 : -1); \
  while (nba)

#define LRT_EDGE_BA_MARCHING_NEXT(fb1, fb2) \
  /* Marching along `e->v1` to `e->v2`, searching each possible bounding areas it may touch. */ \
  nba = lineart_bounding_area_next(nba, fb1, fb2, x, y, k, positive_x, positive_y, &x, &y);

#define LRT_EDGE_BA_MARCHING_END

/**
 * All internal functions starting with lineart_main_ is called inside
 * #MOD_lineart_compute_feature_lines function.
 * This function handles all occlusion calculation.
 */
void lineart_main_occlusion_begin(struct LineartData *ld);
/**
 * This function cuts triangles with near- or far-plane. Setting clip_far = true for cutting with
 * far-plane. For triangles that's crossing the plane, it will generate new 1 or 2 triangles with
 * new topology that represents the trimmed triangle. (which then became a triangle or a square
 * formed by two triangles)
 */
void lineart_main_cull_triangles(struct LineartData *ld, bool clip_far);
/**
 * Adjacent data is only used during the initial stages of computing.
 * So we can free it using this function when it is not needed anymore.
 */
void lineart_main_free_adjacent_data(struct LineartData *ld);
void lineart_main_perspective_division(struct LineartData *ld);
void lineart_main_discard_out_of_frame_edges(struct LineartData *ld);
void lineart_main_load_geometries(struct Depsgraph *depsgraph,
                                  struct Scene *scene,
                                  struct Object *camera,
                                  struct LineartData *ld,
                                  bool allow_duplicates,
                                  bool do_shadow_casting,
                                  ListBaseT<LineartElementLinkNode> *shadow_elns,
                                  Set<const Object *> *included_objects);
/**
 * The calculated view vector will point towards the far-plane from the camera position.
 */
void lineart_main_get_view_vector(struct LineartData *ld);
void lineart_main_bounding_area_make_initial(struct LineartData *ld);
void lineart_main_bounding_areas_connect_post(struct LineartData *ld);
void lineart_main_clear_linked_edges(struct LineartData *ld);
/**
 * Link lines to their respective bounding areas.
 */
void lineart_main_link_lines(struct LineartData *ld);
/**
 * Sequentially add triangles into render buffer, intersection lines between those triangles will
 * also be computed at the same time.
 */
void lineart_main_add_triangles(struct LineartData *ld);
/**
 * This call would internally duplicate #original_ld, override necessary configurations for shadow
 * computations. It will return:
 *
 * 1) Generated shadow edges in format of `LineartElementLinkNode` which can be directly loaded
 * into later main view camera occlusion stage.
 * 2) Shadow render buffer if 3rd stage reprojection is need for silhouette/lit/shaded region
 * selection. Otherwise the shadow render buffer is deleted before this function returns.
 */
bool lineart_main_try_generate_shadow(
    struct Depsgraph *depsgraph,
    struct Scene *scene,
    struct LineartData *original_ld,
    struct LineartGpencilModifierData *lmd_legacy,
    struct LineartStaticMemPool *shadow_data_pool,
    struct LineartElementLinkNode **r_veln,
    struct LineartElementLinkNode **r_eeln,
    ListBaseT<LineartElementLinkNode> *r_calculated_edges_eln_list,
    struct LineartData **r_shadow_ld_if_reproject);
bool lineart_main_try_generate_shadow_v3(
    struct Depsgraph *depsgraph,
    struct Scene *scene,
    struct LineartData *original_ld,
    struct GreasePencilLineartModifierData *lmd,
    struct LineartStaticMemPool *shadow_data_pool,
    struct LineartElementLinkNode **r_veln,
    struct LineartElementLinkNode **r_eeln,
    ListBaseT<LineartElementLinkNode> *r_calculated_edges_eln_list,
    struct LineartData **r_shadow_ld_if_reproject);
/**
 * Does the 3rd stage reprojection, will not re-load objects because #shadow_ld is not deleted.
 * Only re-projects view camera edges and check visibility in light camera, then we can determine
 * whether an edge landed on a lit or shaded area.
 */
void lineart_main_make_enclosed_shapes(struct LineartData *ld, struct LineartData *shadow_ld);
/**
 * Shadow segments needs to be transformed to view-camera space, just like any other objects.
 */
void lineart_main_transform_and_add_shadow(struct LineartData *ld,
                                           struct LineartElementLinkNode *veln,
                                           struct LineartElementLinkNode *eeln);

LineartElementLinkNode *lineart_find_matching_eln(ListBaseT<LineartElementLinkNode> *shadow_elns,
                                                  int obindex);
LineartElementLinkNode *lineart_find_matching_eln_obj(ListBaseT<LineartElementLinkNode> *elns,
                                                      struct Object *ob);
LineartEdge *lineart_find_matching_edge(struct LineartElementLinkNode *shadow_eln,
                                        uint64_t edge_identifier);
/**
 * Cuts the original edge based on the occlusion results under light-camera, if segment
 * is occluded in light-camera, then that segment on the original edge must be shaded.
 */
void lineart_register_shadow_cuts(struct LineartData *ld,
                                  struct LineartEdge *e,
                                  struct LineartEdge *shadow_edge);
void lineart_register_intersection_shadow_cuts(struct LineartData *ld,
                                               ListBaseT<LineartElementLinkNode> *shadow_elns);

bool lineart_edge_from_triangle(const struct LineartTriangle *tri,
                                const struct LineartEdge *e,
                                bool allow_overlapping_edges);
/**
 * This function gets the tile for the point `e->v1`, and later use #lineart_bounding_area_next()
 * to get next along the way.
 */
LineartBoundingArea *lineart_edge_first_bounding_area(struct LineartData *ld,
                                                      double *fbcoord1,
                                                      double *fbcoord2);
/**
 * This march along one render line in image space and
 * get the next bounding area the line is crossing.
 */
LineartBoundingArea *lineart_bounding_area_next(struct LineartBoundingArea *self,
                                                double *fbcoord1,
                                                double *fbcoord2,
                                                double x,
                                                double y,
                                                double k,
                                                int positive_x,
                                                int positive_y,
                                                double *next_x,
                                                double *next_y);
/**
 * Cuts the edge in image space and mark occlusion level for each segment.
 */
void lineart_edge_cut(struct LineartData *ld,
                      struct LineartEdge *e,
                      double start,
                      double end,
                      uchar material_mask_bits,
                      uchar mat_occlusion,
                      uint32_t shadow_bits);
void lineart_add_edge_to_array(struct LineartPendingEdges *pe, struct LineartEdge *e);
void lineart_finalize_object_edge_array_reserve(struct LineartPendingEdges *pe, int count);
void lineart_destroy_render_data_keep_init(struct LineartData *ld);

}  // namespace blender
