#include <stdlib.h>
#include <stdarg.h>
#include <stddef.h>
#include <setjmp.h>
#include <cmocka.h>
#include <string.h>

struct double_linked_list {
  struct double_linked_list *prev;
  struct double_linked_list *next;
  char *data;
};

struct double_linked_list *
make_double_linked_list(char *data)
{
  struct double_linked_list *list =
    (struct double_linked_list *)malloc(sizeof(struct double_linked_list));

  list->data = data;
  list->prev = NULL;
  list->next = NULL;

  return list;
}

void
insert_double_linked_list_before(struct double_linked_list *list, char *data)
{
  struct double_linked_list *prev = make_double_linked_list(data);

  if (list->prev != NULL) {
    prev->prev = list->prev;
  }

  list->prev = prev;
}

void
insert_double_linked_list_after(struct double_linked_list *list, char *data)
{
  struct double_linked_list *next = make_double_linked_list(data);

  if (list->next != NULL) {
    next->next = list->next;
  }

  list->next = next;
}

void
free_double_linked_list(struct double_linked_list *list)
{
  if (list != NULL) {
    if (list->data != NULL) {
      free(list->data);
    }

    struct double_linked_list *prev = list->prev;
    while (prev != NULL) {
      struct double_linked_list *inner = prev;
      prev = prev->prev;

      free(inner->data);
      free(inner);
    }

    struct double_linked_list *next = list->next;
    while (next != NULL) {
      struct double_linked_list *inner = next;
      next = next->next;

      free(inner->data);
      free(inner);
    }

    free(list);
  }
}

static void
test_double_linked_list_initialized_prev_null(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);

  assert_null(list->prev);

  free_double_linked_list(list);
}

static void
test_double_linked_list_initialized_next_null(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);

  assert_null(list->next);

  free_double_linked_list(list);
}

static void
test_double_linked_list_initialized_with_data(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);

  assert_string_equal(list->data, "foo");

  free_double_linked_list(list);
}

static void
test_double_linked_list_insert_before_prev_not_null(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);
  char *beforeData = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "bar");

  insert_double_linked_list_before(list, beforeData);

  assert_non_null(list->prev);

  free_double_linked_list(list);
}

static void
test_double_linked_list_insert_before_prev_is_inserted_data(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);
  char *beforeData = (char *)malloc(sizeof(char) * 4);
  strcpy(beforeData, "bar");

  insert_double_linked_list_before(list, beforeData);

  assert_string_equal(list->prev->data, "bar");

  free_double_linked_list(list);
}

static void
test_double_linked_list_insert_multiple_prev_adds_data(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);
  char *beforeBeforeData = (char *)malloc(sizeof(char) * 4);
  strcpy(beforeBeforeData, "bar");
  char *beforeData = (char *)malloc(sizeof(char) * 4);
  strcpy(beforeData, "qux");

  insert_double_linked_list_before(list, beforeBeforeData);
  insert_double_linked_list_before(list, beforeData);

  assert_non_null(list->prev->prev);

  free_double_linked_list(list);
}

static void
test_double_linked_list_insert_multiple_prev_adds_data_with_data(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);
  char *beforeBeforeData = (char *)malloc(sizeof(char) * 4);
  strcpy(beforeBeforeData, "bar");
  char *beforeData = (char *)malloc(sizeof(char) * 4);
  strcpy(beforeData, "qux");

  insert_double_linked_list_before(list, beforeBeforeData);
  insert_double_linked_list_before(list, beforeData);

  assert_string_equal(list->prev->prev->data, "bar");

  free_double_linked_list(list);
}

static void
test_double_linked_list_insert_after_next_not_null(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);
  char *afterData = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "bar");

  insert_double_linked_list_after(list, afterData);

  assert_non_null(list->next);

  free_double_linked_list(list);
}

static void
test_double_linked_list_insert_after_next_is_inserted_data(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);
  char *afterData = (char *)malloc(sizeof(char) * 4);
  strcpy(afterData, "bar");

  insert_double_linked_list_after(list, afterData);

  assert_string_equal(list->next->data, "bar");

  free_double_linked_list(list);
}

static void
test_double_linked_list_insert_multiple_next_adds_data(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);
  char *afterAfterData = (char *)malloc(sizeof(char) * 4);
  strcpy(afterAfterData, "bar");
  char *afterData = (char *)malloc(sizeof(char) * 4);
  strcpy(afterData, "qux");

  insert_double_linked_list_after(list, afterAfterData);
  insert_double_linked_list_after(list, afterData);

  assert_non_null(list->next->next);

  free_double_linked_list(list);
}

static void
test_double_linked_list_insert_multiple_next_adds_data_with_data(void **state)
{
  (void)state;

  char *data = (char *)malloc(sizeof(char) * 4);
  strcpy(data, "foo");
  struct double_linked_list *list = make_double_linked_list(data);
  char *afterAfterData = (char *)malloc(sizeof(char) * 4);
  strcpy(afterAfterData, "bar");
  char *afterData = (char *)malloc(sizeof(char) * 4);
  strcpy(afterData, "qux");

  insert_double_linked_list_after(list, afterAfterData);
  insert_double_linked_list_after(list, afterData);

  assert_string_equal(list->next->next->data, "bar");

  free_double_linked_list(list);
}

int
main()
{
  const struct CMUnitTest tests[] = {
    cmocka_unit_test(test_double_linked_list_initialized_prev_null),
    cmocka_unit_test(test_double_linked_list_initialized_next_null),
    cmocka_unit_test(test_double_linked_list_initialized_with_data),
    cmocka_unit_test(test_double_linked_list_insert_before_prev_not_null),
    cmocka_unit_test(test_double_linked_list_insert_before_prev_is_inserted_data),
    cmocka_unit_test(test_double_linked_list_insert_multiple_prev_adds_data),
    cmocka_unit_test(test_double_linked_list_insert_multiple_prev_adds_data_with_data),
    cmocka_unit_test(test_double_linked_list_insert_after_next_not_null),
    cmocka_unit_test(test_double_linked_list_insert_after_next_is_inserted_data),
    cmocka_unit_test(test_double_linked_list_insert_multiple_next_adds_data),
    cmocka_unit_test(test_double_linked_list_insert_multiple_next_adds_data_with_data),
  };

  return cmocka_run_group_tests(tests, NULL, NULL);
}