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


void test_topReturnsCorrectValue(void) {
    // 1. Arrange
    int* value1;
    int* value2;
    int* outVal1;
    int* outVal2;
    value1 = malloc(sizeof(int));
    value2 = malloc(sizeof(int));
    StackNode* startNode = NULL;

    // 2. Act
    *value1 = 1234;
    *value2 = 5678;
    startNode = push(startNode, value1);
    // new top node is node 2
    startNode = push(startNode, value2);
    outVal2 = top(startNode);
    // node 1 should now be the top node
    startNode = pop(startNode);
    outVal1 = top(startNode);

    // 3. Assert
    //Also tests for the functionality of 'push'
    TEST_ASSERT_EQUAL_INT32(*value1, *outVal1);
    TEST_ASSERT_EQUAL_INT32(*value2, *outVal2);

    free(value1);
    value1 = NULL;
    free(value2);
    value2 = NULL;
    clearStack(startNode);
}

void test_topReturnsNullOnNotExistingStack(void) {
    // 1. Arrange
    StackNode* startNode = NULL;
    int* data;

    // 2. Act
    data = top(startNode);

    //3. Assert
    TEST_ASSERT_NULL(data);
}

void test_popRemovesElements(void) {
   // 1. Arrange
   StackNode* startNode = NULL;
   
   // 2. Act
   // Entering some Elements into Stack (could be added manually for testing)
   startNode = push(startNode, NULL);
   startNode = push(startNode, NULL);
   startNode = push(startNode, NULL);
   startNode = push(startNode, NULL);
   // Now removing created Elements
   startNode = pop(startNode);
   startNode = pop(startNode);
   startNode = pop(startNode);
   startNode = pop(startNode);

    // 3. Assert
    TEST_ASSERT_NULL(startNode);
}

void setUp(void){

}

void tearDown(void){

}

int main(void) {
    UNITY_BEGIN();

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

    RUN_TEST(test_topReturnsNullOnNotExistingStack);
    RUN_TEST(test_topReturnsCorrectValue);
    RUN_TEST(test_popRemovesElements);

    return UNITY_END();
}