/**
 * Copyright (c) 2026 Dominic Masters
 *
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#include "dusktest.h"
#include "animation/keyframe.h"

static void test_keyframeGetValueInterpolatesLinear(void **state) {
  keyframe_t keyframes[] = {
    { .time = 0.0f, .value = 0.0f, .easing = EASING_LINEAR },
    { .time = 1.0f, .value = 10.0f, .easing = EASING_LINEAR }
  };

  assert_float_equal(keyframeGetValue(keyframes, 2, 0.5f), 5.0f, 0.0001f);
}

static void test_keyframeGetValueClampsAtBoundaries(void **state) {
  keyframe_t keyframes[] = {
    { .time = 0.0f, .value = 0.0f, .easing = EASING_LINEAR },
    { .time = 1.0f, .value = 10.0f, .easing = EASING_LINEAR }
  };

  // Exactly on, and beyond, the final keyframe: holds its value rather
  // than dividing by zero (start == end at that boundary).
  assert_float_equal(keyframeGetValue(keyframes, 2, 1.0f), 10.0f, 0.0001f);
  assert_float_equal(keyframeGetValue(keyframes, 2, 5.0f), 10.0f, 0.0001f);

  // Exactly on the first keyframe: same boundary case at the start.
  assert_float_equal(keyframeGetValue(keyframes, 2, 0.0f), 0.0f, 0.0001f);
}

static void test_keyframeGetValueRespectsEasing(void **state) {
  keyframe_t keyframes[] = {
    { .time = 0.0f, .value = 0.0f, .easing = EASING_IN_QUAD },
    { .time = 1.0f, .value = 10.0f, .easing = EASING_IN_QUAD }
  };

  // easingInQuad(0.5) = 0.25 -> lerp(0, 10, 0.25) = 2.5, not the linear
  // midpoint (5.0).
  assert_float_equal(keyframeGetValue(keyframes, 2, 0.5f), 2.5f, 0.0001f);
}

static void test_keyframeGetValueWithThreeKeyframes(void **state) {
  keyframe_t keyframes[] = {
    { .time = 0.0f, .value = 0.0f, .easing = EASING_LINEAR },
    { .time = 1.0f, .value = 10.0f, .easing = EASING_LINEAR },
    { .time = 2.0f, .value = 0.0f, .easing = EASING_LINEAR }
  };

  assert_float_equal(keyframeGetValue(keyframes, 3, 1.0f), 10.0f, 0.0001f);
  assert_float_equal(keyframeGetValue(keyframes, 3, 1.5f), 5.0f, 0.0001f);
}

int main(int argc, char **argv) {
  const struct CMUnitTest tests[] = {
    cmocka_unit_test(test_keyframeGetValueInterpolatesLinear),
    cmocka_unit_test(test_keyframeGetValueClampsAtBoundaries),
    cmocka_unit_test(test_keyframeGetValueRespectsEasing),
    cmocka_unit_test(test_keyframeGetValueWithThreeKeyframes),
  };

  return cmocka_run_group_tests(tests, NULL, NULL);
}