#include <check.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <ucore/read_file.h>


START_TEST (test_read_file_non_existing_file)
    char *content;
    size_t len;
    int saved_errno;

    content = uc_read_file("non existing file 123765", &len, 1000000000);
    saved_errno = errno;

    fail_if(content != NULL);
    fail_if(saved_errno == 0);
END_TEST

START_TEST (test_read_file_simple)
    char *content;
    const char *filename = "test_read_file_simple";
    size_t len;
    ssize_t rc;

    int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0664);
    fail_if(fd == -1);

    rc = write(fd, "hello", 5);
    fail_if(rc != 5, "rc was %ld", (long)rc);

    close(fd);

    content = uc_read_file(filename, &len, 1000000000);
    unlink(filename);

    fail_if(content == NULL);
    fail_if(len != 5);
    fail_if(strlen(content) != 5);
    fail_if(strcmp("hello", content) != 0);
END_TEST

START_TEST (test_read_file_greater_than_max)
    char *content;
    const char *filename = "test_read_file_simple";
    size_t len;
    ssize_t rc;
    int saved_errno;

    int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0664);
    fail_if(fd == -1);

    rc = write(fd, "hello", 5);
    fail_if(rc != 5, "rc was %ld", (long)rc);

    close(fd);

    content = uc_read_file(filename, &len, 4);
    saved_errno = errno;
    unlink(filename);

    fail_if(content != NULL);
    fail_if(saved_errno != EMSGSIZE, "was %d", saved_errno);
END_TEST

START_TEST (test_read_file_boundary)
    char *content;
    const char *filename = "test_read_file_boundary";
    size_t len;
    ssize_t rc;
    char buf[1030] = "";
    strcpy(&buf[1022], "foobar");

    int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0664);
    fail_if(fd == -1);

    rc = write(fd, buf, sizeof buf);
    fail_if(rc != sizeof buf, "rc was %ld", (long)rc);

    close(fd);

    content = uc_read_file(filename, &len, 1000000000);
    unlink(filename);

    fail_if(content == NULL);
    fail_if(len != sizeof buf);
    fail_if(strcmp("foobar", &content[1022]) != 0);
    free(content);
END_TEST

START_TEST (test_read_file_devnull)
    char *content;
    size_t len = 123;

    content = uc_read_file("/dev/null", &len, 1024);
    fail_if(content == NULL);
    fail_if(len != 0);
    free(content);
    
END_TEST

Suite *read_file_suite(void)
{
    Suite *s = suite_create("read_file");
    TCase *tc = tcase_create("read_file tests");
    tcase_add_test(tc, test_read_file_non_existing_file);
    tcase_add_test(tc, test_read_file_simple);
    tcase_add_test(tc, test_read_file_greater_than_max);
    tcase_add_test(tc, test_read_file_boundary);
    tcase_add_test(tc, test_read_file_devnull);


    suite_add_tcase(s, tc);

    return s;
}