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

void test_push(void)
{
    StackNode *testNode;
    int data = 1;

    // Test für leeren Stack
    testNode = push(NULL, &data);
    TEST_ASSERT_NOT_NULL(&testNode);
    TEST_ASSERT_NULL(testNode->next);
    TEST_ASSERT_EQUAL_INT(1, testNode->value);

    data = 2;

    // Test für nicht leeren Stack
    testNode = push(testNode, &data);
    TEST_ASSERT_NOT_NULL(&testNode);
    TEST_ASSERT_NOT_NULL(testNode->next);
    TEST_ASSERT_NULL(testNode->next->next);
    TEST_ASSERT_EQUAL_INT(1, testNode->value);
    TEST_ASSERT_EQUAL_INT(2, testNode->next->value);
}

StackNode* setup(int value, StackNode* next) {
    StackNode* node = malloc(sizeof(StackNode)); // allocate memory on heap
    if (node == NULL) {
        perror("malloc failed");
        exit(EXIT_FAILURE); // or handle the error differently
    }
    node->value = value;
    node->next = next;
    return node;
}

void test_pop(void)
{   
    StackNode* node2 = setup(3, NULL);
    StackNode* node1 = setup(2, node2);
    StackNode* header = setup(1, node1);
    StackNode* temp;

    temp = pop(header);
    int after = 0;
    while(temp) 
    {
        after++;
        temp = temp->next;
    }

    
    TEST_ASSERT_EQUAL_INT(2, after);
    TEST_ASSERT_NULL(node1->next);
}

void test_top(void)
{
    StackNode* node2 = setup(3, NULL);
    StackNode* node1 = setup(2, node2);
    StackNode* header = setup(1, node1);

    int data = *(int *)top(header);
    TEST_ASSERT_EQUAL_INT(node2->value, data);
}

void test_clear()
{
    StackNode* node2 = setup(3, NULL);
    StackNode* node1 = setup(2, node2);
    StackNode* header = setup(1, node1);
    StackNode* temp;
    
    clearStack(header);
    temp = header;
    
    int after = 0;
    while(temp) 
    {
        after++;
        temp = temp->next;
    }

    
    TEST_ASSERT_NULL(after);
}

void setUp(void)
{
    // Falls notwendig, kann hier Vorbereitungsarbeit gemacht werden
}

void tearDown(void)
{
    // Hier kann Bereinigungsarbeit nach jedem Test durchgeführt werden
}

int main()
{
    UNITY_BEGIN();

    printf("============================\nStack tests\n============================\n");

    RUN_TEST(test_push);
    RUN_TEST(test_pop);
    RUN_TEST(test_top);
    RUN_TEST(test_clear);

    return UNITY_END();
}