#include <assert.h>
#include <errno.h>

#include <user/stdio.h>
#include <user/syscall.h>
#include <user/wait.h>

void test_fork_wait1(void)
{
	ssize_t pid = fork();

	assert(pid >= 0);

	if (pid == 0)
		exit(114);
	
	int wstatus;
	assert(pid == wait(&wstatus));

	assert(WEXITSTATUS(wstatus) == 114);

	printf("\x1b[92mtest_fork_wait1 passed!\x1b[0m\n");
}

void test_fork_wait2(void)
{
	ssize_t pid = fork();

	assert(pid >= 0);

	if (pid == 0)
		exit(514);
	
	assert(pid == wait(NULL));

	printf("\x1b[92mtest_fork_wait2 passed!\x1b[0m\n");
}

void test_empty_wait(void)
{
	assert(wait(NULL) == -ECHILD);

	printf("\x1b[92mtest_empty_wait passed!\x1b[0m\n");
}

void test_fork_limit(void)
{
	int xor_sum = 0;

	for (int i = 1 ; i <= 17 ; i++) {
		ssize_t pid = fork();

		assert(pid >= 0);

		if (pid == 0)
			exit(0);
		
		xor_sum ^= pid;
	}

	assert(fork() == -EAGAIN);
	
	int wait_cnt = 0, wait_pid;
	while ((wait_pid = wait(NULL)) >= 0)
		wait_cnt++, xor_sum ^= wait_pid;
	
	assert(wait_cnt == 17);
	assert(xor_sum == 0);
	
	printf("\x1b[92mtest_fork_limit passed!\x1b[0m\n");
}

void test_wait_is_sleeping(void)
{
	ssize_t rt_pid = get_pid();

	for (int i = 1 ; i <= 17 ; i++) {
		ssize_t pid = fork();

		assert(pid >= 0);
		
		if (pid > 0) {
			int wstatus;
			assert(pid == wait(&wstatus));
			assert(WEXITSTATUS(wstatus) == 42);
			if (get_pid() != rt_pid)
				exit(42);
			break;
		}
	}

	if (get_pid() != rt_pid) {
		ssize_t la_ticks = get_ticks();
		
		for (int i = 1 ; i <= (int)5e6 ; i++) {
			ssize_t now_ticks = get_ticks();
			assert(now_ticks - la_ticks <= 2);
			la_ticks = now_ticks;
		}

		exit(42);
	}

	printf("\x1b[92mtest_wait_is_sleeping passed!\x1b[0m\n");
}

int main()
{
	test_fork_wait1();
	test_fork_wait2();
	test_empty_wait();
	test_fork_limit();
	test_wait_is_sleeping();
	printf("\x1b[92mall tests passed!\x1b[0m\n");
}