#include <stdio.h>
#include <stdlib.h>
#include "unity.h"
#include "bintree.h"

/* ---------- Helper ---------- */

int compareInt(const void *a, const void *b)
{
    int ia = *(const int *)a;
    int ib = *(const int *)b;
    return ia - ib;
}

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

/* ---------- addToTree ---------- */

void test_addToTree_adds_first_element(void)
{
    TreeNode *root = NULL;
    int value = 5;
    int isDup = -1;

    root = addToTree(root, &value, sizeof(int), compareInt, &isDup);

    TEST_ASSERT_NOT_NULL(root);
    TEST_ASSERT_EQUAL_INT(0, isDup);
    TEST_ASSERT_EQUAL_INT(1, treeSize(root));

    clearTree(root);
}

void test_addToTree_detects_duplicate(void)
{
    TreeNode *root = NULL;
    int value = 5;
    int isDup = -1;

    root = addToTree(root, &value, sizeof(int), compareInt, &isDup);
    root = addToTree(root, &value, sizeof(int), compareInt, &isDup);

    TEST_ASSERT_EQUAL_INT(1, isDup);
    TEST_ASSERT_EQUAL_INT(1, treeSize(root));

    clearTree(root);
}

/* ---------- treeSize ---------- */

void test_treeSize_counts_multiple_elements(void)
{
    TreeNode *root = NULL;
    int values[] = {5, 2, 8, 1, 3};

    for (int i = 0; i < 5; i++)
        root = addToTree(root, &values[i], sizeof(int), compareInt, NULL);

    TEST_ASSERT_EQUAL_UINT(5, treeSize(root));

    clearTree(root);
}

/* ---------- nextTreeData ---------- */

void test_nextTreeData_returns_sorted_order(void)
{
    TreeNode *root = NULL;
    int values[] = {5, 2, 8, 1, 3};

    for (int i = 0; i < 5; i++)
        root = addToTree(root, &values[i], sizeof(int), compareInt, NULL);

    int expected[] = {1, 2, 3, 5, 8};

    int *val;

    /* erster Aufruf initialisiert den Iterator */
    val = (int *)nextTreeData(root);
    TEST_ASSERT_NOT_NULL(val);
    TEST_ASSERT_EQUAL_INT(expected[0], *val);

    /* weitere Aufrufe liefern die nächsten Elemente */
    for (int i = 1; i < 5; i++)
    {
        val = (int *)nextTreeData(NULL);
        TEST_ASSERT_NOT_NULL(val);
        TEST_ASSERT_EQUAL_INT(expected[i], *val);
    }

    /* danach muss NULL kommen */
    TEST_ASSERT_NULL(nextTreeData(NULL));

    clearTree(root);
}

/* ---------- clearTree ---------- */

void test_clearTree_on_empty_tree_does_not_crash(void)
{
    clearTree(NULL);
    TEST_PASS();
}

/* ---------- MAIN ---------- */

int main(void)
{
    UNITY_BEGIN();

    RUN_TEST(test_addToTree_adds_first_element);
    RUN_TEST(test_addToTree_detects_duplicate);

    RUN_TEST(test_treeSize_counts_multiple_elements);

    RUN_TEST(test_nextTreeData_returns_sorted_order);

    RUN_TEST(test_clearTree_on_empty_tree_does_not_crash);

    return UNITY_END();
}