#include <unity.h>
#include "BuddyLogic.h"

static int32_t fixed_rng(int32_t lo, int32_t hi) { (void)hi; return lo; }

void setUp()    {}
void tearDown() {}

// ── initBuddy ──────────────────────────────────────────────────────────────

void test_initBuddy_sets_open_blink() {
    BuddyState b{};
    initBuddy(b, 0);
    TEST_ASSERT_EQUAL(BLINK_OPEN, b.blinkState);
    TEST_ASSERT_EQUAL(EYE_RY,     b.blinkRy);
}

void test_initBuddy_sets_normal_mood() {
    BuddyState b{};
    initBuddy(b, 0);
    TEST_ASSERT_EQUAL(MOOD_NORMAL, b.mood);
}

void test_initBuddy_timestamps_relative_to_now() {
    BuddyState b{};
    initBuddy(b, 1000);
    TEST_ASSERT_EQUAL(1000u,        b.lastEvent);
    TEST_ASSERT_EQUAL(1000u + 3000, b.nextBlink);
    TEST_ASSERT_EQUAL(1000u + 2000, b.nextLook);
}

// ── setBuddyMood ───────────────────────────────────────────────────────────

void test_setBuddyMood_no_duration_sets_revertAt_zero() {
    BuddyState b{};
    initBuddy(b, 0);
    setBuddyMood(b, MOOD_HAPPY, 1000, 0);
    TEST_ASSERT_EQUAL(0u, b.revertAt);
}

void test_setBuddyMood_with_duration_sets_revertAt() {
    BuddyState b{};
    initBuddy(b, 0);
    setBuddyMood(b, MOOD_HAPPY, 1000, 4000);
    TEST_ASSERT_EQUAL(5000u, b.revertAt);
}

void test_setBuddyMood_updates_lastEvent() {
    BuddyState b{};
    initBuddy(b, 0);
    setBuddyMood(b, MOOD_HAPPY, 5000);
    TEST_ASSERT_EQUAL(5000u, b.lastEvent);
}

void test_setBuddyMood_happy_sets_pupil_target_up() {
    BuddyState b{};
    initBuddy(b, 0);
    setBuddyMood(b, MOOD_HAPPY, 0);
    TEST_ASSERT_EQUAL( 0, b.pupilTargetDx);
    TEST_ASSERT_EQUAL(-2, b.pupilTargetDy);
}

void test_setBuddyMood_sad_sets_pupil_target_down() {
    BuddyState b{};
    initBuddy(b, 0);
    setBuddyMood(b, MOOD_SAD, 0);
    TEST_ASSERT_EQUAL(0, b.pupilTargetDx);
    TEST_ASSERT_EQUAL(4, b.pupilTargetDy);
}

// ── updateBuddyAnim — mood revert ─────────────────────────────────────────

void test_updateBuddyAnim_reverts_mood_when_revertAt_passed() {
    BuddyState b{};
    initBuddy(b, 0);
    setBuddyMood(b, MOOD_HAPPY, 0, 4000);   // revertAt = 4000
    updateBuddyAnim(b, 5000, fixed_rng);    // now > revertAt
    TEST_ASSERT_EQUAL(MOOD_NORMAL, b.mood);
    TEST_ASSERT_EQUAL(0u,          b.revertAt);
}

void test_updateBuddyAnim_does_not_revert_before_revertAt() {
    BuddyState b{};
    initBuddy(b, 0);
    setBuddyMood(b, MOOD_HAPPY, 0, 4000);
    updateBuddyAnim(b, 3999, fixed_rng);
    TEST_ASSERT_EQUAL(MOOD_HAPPY, b.mood);
}

void test_updateBuddyAnim_goes_sleepy_after_idle() {
    BuddyState b{};
    initBuddy(b, 0);   // lastEvent = 0, mood = NORMAL
    updateBuddyAnim(b, 300001, fixed_rng);
    TEST_ASSERT_EQUAL(MOOD_SLEEPY, b.mood);
}

void test_updateBuddyAnim_no_sleepy_before_idle() {
    BuddyState b{};
    initBuddy(b, 0);
    updateBuddyAnim(b, 299999, fixed_rng);
    TEST_ASSERT_EQUAL(MOOD_NORMAL, b.mood);
}

// ── Blink state machine ────────────────────────────────────────────────────

void test_blink_open_to_closing_when_nextBlink_passed() {
    BuddyState b{};
    initBuddy(b, 0);   // nextBlink = 3000
    updateBuddyAnim(b, 3001, fixed_rng);
    TEST_ASSERT_EQUAL(BLINK_CLOSING, b.blinkState);
}

void test_blink_closing_decrements_blinkRy() {
    BuddyState b{};
    initBuddy(b, 0);
    b.blinkState = BLINK_CLOSING;
    b.blinkRy    = 15;
    updateBuddyAnim(b, 0, fixed_rng);
    TEST_ASSERT_EQUAL(11, b.blinkRy);
    TEST_ASSERT_EQUAL(BLINK_CLOSING, b.blinkState);
}

void test_blink_closing_reaches_closed_when_small() {
    BuddyState b{};
    initBuddy(b, 0);
    b.blinkState = BLINK_CLOSING;
    b.blinkRy    = 3;
    updateBuddyAnim(b, 0, fixed_rng);
    TEST_ASSERT_EQUAL(BLINK_CLOSED, b.blinkState);
    TEST_ASSERT_EQUAL(1, b.blinkRy);
}

void test_blink_closed_ticks_to_opening() {
    BuddyState b{};
    initBuddy(b, 0);
    b.blinkState  = BLINK_CLOSED;
    b.closedTicks = 2;
    updateBuddyAnim(b, 0, fixed_rng);
    TEST_ASSERT_EQUAL(BLINK_OPENING, b.blinkState);
}

void test_blink_opening_increments_blinkRy() {
    BuddyState b{};
    initBuddy(b, 0);
    b.blinkState = BLINK_OPENING;
    b.blinkRy    = 7;   // 7+4=11 < EYE_RY(15), stays OPENING
    updateBuddyAnim(b, 0, fixed_rng);
    TEST_ASSERT_EQUAL(11,           b.blinkRy);
    TEST_ASSERT_EQUAL(BLINK_OPENING, b.blinkState);
}

void test_blink_opening_returns_to_open_at_eye_ry() {
    BuddyState b{};
    initBuddy(b, 0);
    b.blinkState = BLINK_OPENING;
    b.blinkRy    = 13;  // 13+4=17 >= EYE_RY(15) → OPEN
    updateBuddyAnim(b, 0, fixed_rng);
    TEST_ASSERT_EQUAL(BLINK_OPEN, b.blinkState);
    TEST_ASSERT_EQUAL(EYE_RY,     b.blinkRy);
}

void test_surprised_does_not_blink() {
    BuddyState b{};
    initBuddy(b, 0);
    setBuddyMood(b, MOOD_SURPRISED, 0);
    b.nextBlink = 0;    // past-due
    updateBuddyAnim(b, 1000, fixed_rng);
    TEST_ASSERT_EQUAL(BLINK_OPEN, b.blinkState);  // no transition
    TEST_ASSERT_EQUAL(EYE_RY,     b.blinkRy);     // stays full
}

// ── Pupil saccade ──────────────────────────────────────────────────────────

void test_pupil_moves_fast_when_far() {
    BuddyState b{};
    initBuddy(b, 0);
    b.pupilDx       = 0;
    b.pupilTargetDx = 8;  // |delta| = 8 >= 4 → step 3
    b.pupilDy = b.pupilTargetDy = 0;
    updateBuddyAnim(b, 0, fixed_rng);
    TEST_ASSERT_EQUAL(3, b.pupilDx);
}

void test_pupil_moves_slow_when_close() {
    BuddyState b{};
    initBuddy(b, 0);
    b.pupilDx       = 0;
    b.pupilTargetDx = 2;  // |delta| = 2 < 4 → step 1
    b.pupilDy = b.pupilTargetDy = 0;
    updateBuddyAnim(b, 0, fixed_rng);
    TEST_ASSERT_EQUAL(1, b.pupilDx);
}

// ── main ──────────────────────────────────────────────────────────────────

int main() {
    UNITY_BEGIN();
    RUN_TEST(test_initBuddy_sets_open_blink);
    RUN_TEST(test_initBuddy_sets_normal_mood);
    RUN_TEST(test_initBuddy_timestamps_relative_to_now);
    RUN_TEST(test_setBuddyMood_no_duration_sets_revertAt_zero);
    RUN_TEST(test_setBuddyMood_with_duration_sets_revertAt);
    RUN_TEST(test_setBuddyMood_updates_lastEvent);
    RUN_TEST(test_setBuddyMood_happy_sets_pupil_target_up);
    RUN_TEST(test_setBuddyMood_sad_sets_pupil_target_down);
    RUN_TEST(test_updateBuddyAnim_reverts_mood_when_revertAt_passed);
    RUN_TEST(test_updateBuddyAnim_does_not_revert_before_revertAt);
    RUN_TEST(test_updateBuddyAnim_goes_sleepy_after_idle);
    RUN_TEST(test_updateBuddyAnim_no_sleepy_before_idle);
    RUN_TEST(test_blink_open_to_closing_when_nextBlink_passed);
    RUN_TEST(test_blink_closing_decrements_blinkRy);
    RUN_TEST(test_blink_closing_reaches_closed_when_small);
    RUN_TEST(test_blink_closed_ticks_to_opening);
    RUN_TEST(test_blink_opening_increments_blinkRy);
    RUN_TEST(test_blink_opening_returns_to_open_at_eye_ry);
    RUN_TEST(test_surprised_does_not_blink);
    RUN_TEST(test_pupil_moves_fast_when_far);
    RUN_TEST(test_pupil_moves_slow_when_close);
    return UNITY_END();
}