/* SPDX-License-Identifier: GPL-2.0-or-later
 * Copyright 2020 Blender Foundation. */
#include "testing/testing.h"

#include "MEM_guardedalloc.h"

#include "BKE_fcurve.h"

#include "ED_keyframing.h"

#include "DNA_anim_types.h"

namespace blender::bke::tests {

/* Epsilon for floating point comparisons. */
static const float EPSILON = 1e-7f;

TEST(evaluate_fcurve, EmptyFCurve)
{
  FCurve *fcu = BKE_fcurve_create();
  EXPECT_EQ(evaluate_fcurve(fcu, 47.0f), 0.0f);
  BKE_fcurve_free(fcu);
}

TEST(evaluate_fcurve, OnKeys)
{
  FCurve *fcu = BKE_fcurve_create();

  insert_vert_fcurve(fcu, 1.0f, 7.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF);
  insert_vert_fcurve(fcu, 2.0f, 13.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF);
  insert_vert_fcurve(fcu, 3.0f, 19.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF);

  EXPECT_NEAR(evaluate_fcurve(fcu, 1.0f), 7.0f, EPSILON);  /* hits 'on or before first' function */
  EXPECT_NEAR(evaluate_fcurve(fcu, 2.0f), 13.0f, EPSILON); /* hits 'between' function */
  EXPECT_NEAR(evaluate_fcurve(fcu, 3.0f), 19.0f, EPSILON); /* hits 'on or after last' function */

  /* Also test within a specific time epsilon of the keys, as this was an issue in T39207.
   * This epsilon is just slightly smaller than the epsilon given to
   * BKE_fcurve_bezt_binarysearch_index_ex() in fcurve_eval_between_keyframes(), so it should hit
   * the "exact" code path. */
  float time_epsilon = 0.00008f;
  EXPECT_NEAR(evaluate_fcurve(fcu, 2.0f - time_epsilon), 13.0f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 2.0f + time_epsilon), 13.0f, EPSILON);

  BKE_fcurve_free(fcu);
}

TEST(evaluate_fcurve, InterpolationConstant)
{
  FCurve *fcu = BKE_fcurve_create();

  EXPECT_EQ(insert_vert_fcurve(fcu, 1.0f, 7.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 0);
  EXPECT_EQ(insert_vert_fcurve(fcu, 2.0f, 13.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 1);

  fcu->bezt[0].ipo = BEZT_IPO_CONST;
  fcu->bezt[1].ipo = BEZT_IPO_CONST;

  EXPECT_NEAR(evaluate_fcurve(fcu, 1.25f), 7.0f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 1.50f), 7.0f, EPSILON);

  BKE_fcurve_free(fcu);
}

TEST(evaluate_fcurve, InterpolationLinear)
{
  FCurve *fcu = BKE_fcurve_create();

  EXPECT_EQ(insert_vert_fcurve(fcu, 1.0f, 7.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 0);
  EXPECT_EQ(insert_vert_fcurve(fcu, 2.0f, 13.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 1);

  fcu->bezt[0].ipo = BEZT_IPO_LIN;
  fcu->bezt[1].ipo = BEZT_IPO_LIN;

  EXPECT_NEAR(evaluate_fcurve(fcu, 1.25f), 8.5f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 1.50f), 10.0f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 1.75f), 11.5f, EPSILON);

  BKE_fcurve_free(fcu);
}

TEST(evaluate_fcurve, InterpolationBezier)
{
  FCurve *fcu = BKE_fcurve_create();

  EXPECT_EQ(insert_vert_fcurve(fcu, 1.0f, 7.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 0);
  EXPECT_EQ(insert_vert_fcurve(fcu, 2.0f, 13.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 1);

  EXPECT_EQ(fcu->bezt[0].ipo, BEZT_IPO_BEZ);
  EXPECT_EQ(fcu->bezt[1].ipo, BEZT_IPO_BEZ);

  /* Test with default handles. */
  EXPECT_NEAR(evaluate_fcurve(fcu, 1.25f), 7.8297067f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 1.50f), 10.0f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 1.75f), 12.170294f, EPSILON);

  /* Test with modified handles. */
  fcu->bezt[0].vec[0][0] = 0.71855f; /* left handle X */
  fcu->bezt[0].vec[0][1] = 6.22482f; /* left handle Y */
  fcu->bezt[0].vec[2][0] = 1.35148f; /* right handle X */
  fcu->bezt[0].vec[2][1] = 7.96806f; /* right handle Y */

  fcu->bezt[1].vec[0][0] = 1.66667f; /* left handle X */
  fcu->bezt[1].vec[0][1] = 10.4136f; /* left handle Y */
  fcu->bezt[1].vec[2][0] = 2.33333f; /* right handle X */
  fcu->bezt[1].vec[2][1] = 15.5864f; /* right handle Y */

  EXPECT_NEAR(evaluate_fcurve(fcu, 1.25f), 7.945497f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 1.50f), 9.3495407f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 1.75f), 11.088551f, EPSILON);

  BKE_fcurve_free(fcu);
}

TEST(evaluate_fcurve, InterpolationBounce)
{
  FCurve *fcu = BKE_fcurve_create();

  EXPECT_EQ(insert_vert_fcurve(fcu, 1.0f, 7.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 0);
  EXPECT_EQ(insert_vert_fcurve(fcu, 2.0f, 13.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 1);

  fcu->bezt[0].ipo = BEZT_IPO_BOUNCE;
  fcu->bezt[1].ipo = BEZT_IPO_BOUNCE;

  fcu->bezt[0].easing = BEZT_IPO_EASE_IN;
  fcu->bezt[1].easing = BEZT_IPO_EASE_AUTO;

  EXPECT_NEAR(evaluate_fcurve(fcu, 1.4f), 8.3649998f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 1.5f), 8.4062500f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 1.8f), 11.184999f, EPSILON);

  BKE_fcurve_free(fcu);
}

TEST(evaluate_fcurve, ExtrapolationLinearKeys)
{
  FCurve *fcu = BKE_fcurve_create();

  EXPECT_EQ(insert_vert_fcurve(fcu, 1.0f, 7.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 0);
  EXPECT_EQ(insert_vert_fcurve(fcu, 2.0f, 13.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 1);
  fcu->bezt[0].ipo = BEZT_IPO_LIN;
  fcu->bezt[1].ipo = BEZT_IPO_LIN;

  fcu->extend = FCURVE_EXTRAPOLATE_LINEAR;
  /* Before first keyframe. */
  EXPECT_NEAR(evaluate_fcurve(fcu, 0.75f), 5.5f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 0.50f), 4.0f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, -1.50f), -8.0f, EPSILON);
  /* After last keyframe. */
  EXPECT_NEAR(evaluate_fcurve(fcu, 2.75f), 17.5f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 3.50f), 22.0f, EPSILON);

  fcu->extend = FCURVE_EXTRAPOLATE_CONSTANT;
  /* Before first keyframe. */
  EXPECT_NEAR(evaluate_fcurve(fcu, 0.75f), 7.0f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, -1.50f), 7.0f, EPSILON);
  /* After last keyframe. */
  EXPECT_NEAR(evaluate_fcurve(fcu, 2.75f), 13.0f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 3.50f), 13.0f, EPSILON);

  BKE_fcurve_free(fcu);
}

TEST(evaluate_fcurve, ExtrapolationBezierKeys)
{
  FCurve *fcu = BKE_fcurve_create();

  EXPECT_EQ(insert_vert_fcurve(fcu, 1.0f, 7.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 0);
  EXPECT_EQ(insert_vert_fcurve(fcu, 2.0f, 13.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 1);

  fcu->bezt[0].vec[0][0] = 0.71855f; /* left handle X */
  fcu->bezt[0].vec[0][1] = 6.22482f; /* left handle Y */
  fcu->bezt[0].vec[2][0] = 1.35148f; /* right handle X */
  fcu->bezt[0].vec[2][1] = 7.96806f; /* right handle Y */

  fcu->bezt[1].vec[0][0] = 1.66667f; /* left handle X */
  fcu->bezt[1].vec[0][1] = 10.4136f; /* left handle Y */
  fcu->bezt[1].vec[2][0] = 2.33333f; /* right handle X */
  fcu->bezt[1].vec[2][1] = 15.5864f; /* right handle Y */

  fcu->extend = FCURVE_EXTRAPOLATE_LINEAR;
  /* Before first keyframe. */
  EXPECT_NEAR(evaluate_fcurve(fcu, 0.75f), 6.3114409f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, -0.50f), 2.8686447f, EPSILON);
  /* After last keyframe. */
  EXPECT_NEAR(evaluate_fcurve(fcu, 2.75f), 18.81946f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 3.50f), 24.63892f, EPSILON);

  fcu->extend = FCURVE_EXTRAPOLATE_CONSTANT;
  /* Before first keyframe. */
  EXPECT_NEAR(evaluate_fcurve(fcu, 0.75f), 7.0f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, -1.50f), 7.0f, EPSILON);
  /* After last keyframe. */
  EXPECT_NEAR(evaluate_fcurve(fcu, 2.75f), 13.0f, EPSILON);
  EXPECT_NEAR(evaluate_fcurve(fcu, 3.50f), 13.0f, EPSILON);

  BKE_fcurve_free(fcu);
}

TEST(fcurve_subdivide, BKE_fcurve_bezt_subdivide_handles)
{
  FCurve *fcu = BKE_fcurve_create();

  /* Insert two keyframes and set handles to something non-default. */
  EXPECT_EQ(insert_vert_fcurve(fcu, 1.0f, 0.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 0);
  EXPECT_EQ(insert_vert_fcurve(fcu, 13.0f, 2.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 1);

  fcu->bezt[0].h1 = fcu->bezt[0].h2 = HD_FREE;
  fcu->bezt[0].vec[0][0] = -5.0f;
  fcu->bezt[0].vec[0][1] = 0.0f;
  fcu->bezt[0].vec[2][0] = 2.0f;
  fcu->bezt[0].vec[2][1] = 4.0f;

  fcu->bezt[1].h1 = fcu->bezt[1].h2 = HD_FREE;
  fcu->bezt[1].vec[0][0] = 13.0f;
  fcu->bezt[1].vec[0][1] = -2.0f;
  fcu->bezt[1].vec[2][0] = 16.0f;
  fcu->bezt[1].vec[2][1] = -3.0f;

  /* Create new keyframe point with defaults from insert_vert_fcurve(). */
  BezTriple beztr;
  const float x = 7.375f; /* at this X-coord, the FCurve should evaluate to 1.000f. */
  const float y = 1.000f;
  beztr.vec[0][0] = x - 1.0f;
  beztr.vec[0][1] = y;
  beztr.vec[1][0] = x;
  beztr.vec[1][1] = y;
  beztr.vec[2][0] = x + 1.0f;
  beztr.vec[2][1] = y;
  beztr.h1 = beztr.h2 = HD_AUTO_ANIM;
  beztr.ipo = BEZT_IPO_BEZ;

  /* This should update the existing handles as well as the new BezTriple. */
  float y_delta;
  BKE_fcurve_bezt_subdivide_handles(&beztr, &fcu->bezt[0], &fcu->bezt[1], &y_delta);

  EXPECT_FLOAT_EQ(y_delta, 0.0f);

  EXPECT_FLOAT_EQ(fcu->bezt[0].vec[0][0], -5.0f); /* Left handle should not be touched. */
  EXPECT_FLOAT_EQ(fcu->bezt[0].vec[0][1], 0.0f);
  EXPECT_FLOAT_EQ(fcu->bezt[0].vec[1][0], 1.0f); /* Coordinates should not be touched. */
  EXPECT_FLOAT_EQ(fcu->bezt[0].vec[1][1], 0.0f);
  EXPECT_FLOAT_EQ(fcu->bezt[0].vec[2][0], 1.5f); /* Right handle should be updated. */
  EXPECT_FLOAT_EQ(fcu->bezt[0].vec[2][1], 2.0f);

  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[0][0], 13.0f); /* Left handle should be updated. */
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[0][1], 0.0f);
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[1][0], 13.0f); /* Coordinates should not be touched. */
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[1][1], 2.0f);
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[2][0], 16.0f); /* Right handle should not be touched */
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[2][1], -3.0f);

  EXPECT_FLOAT_EQ(beztr.vec[0][0], 4.5f); /* Left handle should be updated. */
  EXPECT_FLOAT_EQ(beztr.vec[0][1], 1.5f);
  EXPECT_FLOAT_EQ(beztr.vec[1][0], 7.375f); /* Coordinates should not be touched. */
  EXPECT_FLOAT_EQ(beztr.vec[1][1], 1.0f);
  EXPECT_FLOAT_EQ(beztr.vec[2][0], 10.250); /* Right handle should be updated. */
  EXPECT_FLOAT_EQ(beztr.vec[2][1], 0.5);

  BKE_fcurve_free(fcu);
}

TEST(fcurve_active_keyframe, ActiveKeyframe)
{
  FCurve *fcu = BKE_fcurve_create();

  /* There should be no active keyframe with no points. */
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), FCURVE_ACTIVE_KEYFRAME_NONE);

  /* Check that adding new points sets the active index. */
  EXPECT_EQ(insert_vert_fcurve(fcu, 1.0f, 7.5f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 0);
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), 0);
  EXPECT_EQ(insert_vert_fcurve(fcu, 8.0f, 15.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 1);
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), 1);
  EXPECT_EQ(insert_vert_fcurve(fcu, 14.0f, 8.2f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF), 2);
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), 2);

  /* Check clearing the index. */
  BKE_fcurve_active_keyframe_set(fcu, nullptr);
  EXPECT_EQ(fcu->active_keyframe_index, FCURVE_ACTIVE_KEYFRAME_NONE);
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), FCURVE_ACTIVE_KEYFRAME_NONE);

  /* Check a "normal" action. */
  fcu->bezt[2].f2 |= SELECT;
  BKE_fcurve_active_keyframe_set(fcu, &fcu->bezt[2]);
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), 2);

  /* Check setting an unselected keyframe as active. */
  fcu->bezt[2].f1 = fcu->bezt[2].f2 = fcu->bezt[2].f3 = 0;
  EXPECT_BLI_ASSERT(BKE_fcurve_active_keyframe_set(fcu, &fcu->bezt[2]),
                    "active keyframe must be selected");
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), FCURVE_ACTIVE_KEYFRAME_NONE);

  /* Check out of bounds (lower). */
  BKE_fcurve_active_keyframe_set(fcu, fcu->bezt - 20);
  EXPECT_EQ(fcu->active_keyframe_index, FCURVE_ACTIVE_KEYFRAME_NONE)
      << "Setting out-of-bounds value via the API should result in valid active_keyframe_index";
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), FCURVE_ACTIVE_KEYFRAME_NONE);

  fcu->active_keyframe_index = -20;
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), FCURVE_ACTIVE_KEYFRAME_NONE)
      << "Even with active_keyframe_index out of bounds, getting it via the API should produce a "
         "valid value";

  /* Check out of bounds (higher). */
  BKE_fcurve_active_keyframe_set(fcu, fcu->bezt + 4);
  EXPECT_EQ(fcu->active_keyframe_index, FCURVE_ACTIVE_KEYFRAME_NONE)
      << "Setting out-of-bounds value via the API should result in valid active_keyframe_index";
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), FCURVE_ACTIVE_KEYFRAME_NONE);

  fcu->active_keyframe_index = fcu->totvert;
  EXPECT_EQ(BKE_fcurve_active_keyframe_index(fcu), FCURVE_ACTIVE_KEYFRAME_NONE)
      << "Even with active_keyframe_index out of bounds, getting it via the API should produce a "
         "valid value";

  BKE_fcurve_free(fcu);
}

TEST(BKE_fcurve, BKE_fcurve_keyframe_move_value_with_handles)
{
  FCurve *fcu = BKE_fcurve_create();

  insert_vert_fcurve(fcu, 1.0f, 7.5f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF);
  insert_vert_fcurve(fcu, 8.0f, 15.0f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF);
  insert_vert_fcurve(fcu, 14.0f, 8.2f, BEZT_KEYTYPE_KEYFRAME, INSERTKEY_NO_USERPREF);

  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[0][0], 5.2671194f);
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[0][1], 15.0f);

  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[1][0], 8.0f);
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[1][1], 15.0f);

  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[2][0], 10.342469f);
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[2][1], 15.0f);

  BKE_fcurve_keyframe_move_value_with_handles(&fcu->bezt[1], 47.0f);

  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[0][0], 5.2671194f) << "Left handle should not move in time";
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[0][1], 47.0f) << "Left handle value should have been updated";

  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[1][0], 8.0f) << "Frame should not move in time";
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[1][1], 47.0f) << "Frame value should have been updated";

  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[2][0], 10.342469f) << "Right handle should not move in time";
  EXPECT_FLOAT_EQ(fcu->bezt[1].vec[2][1], 47.0f) << "Right handle value should have been updated";

  BKE_fcurve_free(fcu);
}

}  // namespace blender::bke::tests