#include <ft/test.h>
#include <ft/all-tests.h>
#include <ft/util.h>

#include <gint/gint.h>

#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>

#include "util.h"

static void _stdio_open_switch(ft_test *t)
{
	int fd, rc;
	FILE *fp;

	/* Create a basic file */
	DO_E(fd, creat("ft_stdio.txt", 0755), t, "%d");
	ft_assert(t, fd >= 0);
	DO_E(rc, write(fd, "Hello, stdio!\n", 14), t, "%d");
	ft_assert(t, rc == 14);
	DO_E(rc, close(fd), t, "%d");
	ft_assert(t, rc == 0);

	/* Try to open it with <stdio.h> */
	DO_E(fp, fopen("ft_stdio.txt", "r"), t, "%p");
	ft_assert(t, fp != NULL);
	ft_log_FILE(t, "", fp);
	if(!fp) return;

	/* Change buffer settings a couple times */
	DO_E(rc, setvbuf(fp, NULL, _IONBF, 0), t, "%d");
	ft_assert(t, rc == 0);
	ft_log_FILE(t, "", fp);
	DO_E(rc, setvbuf(fp, NULL, _IOLBF, 1024), t, "%d");
	ft_assert(t, rc == 0);
	ft_log_FILE(t, "", fp);
	DO_E(rc, setvbuf(fp, NULL, _IOFBF, BUFSIZ), t, "%d");
	ft_assert(t, rc == 0);
	ft_log_FILE(t, "", fp);

	/* Reopen with different permissions */
	DO_E(fp, freopen("ft_stdio.txt", "w+", fp), t, "%p");
	ft_assert(t, fp != NULL);
	ft_log_FILE(t, "", fp);
	DO_E(fp, freopen("ft_stdio.txt", "rb+", fp), t, "%p");
	ft_assert(t, fp != NULL);
	ft_log_FILE(t, "", fp);
	DO_E(fp, freopen("ft_stdio.txt", "ab", fp), t, "%p");
	ft_assert(t, fp != NULL);
	ft_log_FILE(t, "", fp);
	DO_E(fp, freopen("ft_stdio.txt", "w", fp), t, "%p");
	ft_assert(t, fp != NULL);
	ft_log_FILE(t, "", fp);

	DO_E(rc, fclose(fp), t, "%d");
	ft_assert(t, rc == 0);
}

static void _stdio_open(ft_test *t)
{
	gint_world_switch(GINT_CALL(_stdio_open_switch, (void *)t));
}

ft_test ft_stdio_open = {
	.name = "Opening files",
	.function = _stdio_open,
};

static char const *filler =
"The fread function reads, into the array pointed to by ptr, up to nmemb "
"elements whose size is specified by size, from the stream pointed to by "
"stream. For each object, size calls are made to the fgetc function and the "
"results stored, in the order read, in an array of unsigned char exactly "
"overlaying the object. The file position indicator for the stream (if "
"defined) is advanced by the number of characters successfully read. If an "
"error occurs, the resulting value of the file position indicator for the "
"stream is indeterminate. If a partial element is read, its value is "
"indeterminate.\n"; /* length 591 */

static void _ft_stdio_simple_read_switch(ft_test *t)
{
	int fd, rc;
	FILE *fp;
	char *str = malloc(384);

	/* Create a basic large file (compared to its buffer size) */
	DO_E(fd, creat("ft_stdio.txt", 0755), t, "%d");
	ft_assert(t, fd >= 0);
	DO_E(rc, write(fd, filler, 591), t, "%d");
	ft_assert(t, rc == 591);
	DO_E(rc, close(fd), t, "%d");
	ft_assert(t, rc == 0);

	/* Read it through a buffer of size 128 */
	DO_E(fp, fopen("ft_stdio.txt", "r"), t, "%p");
	ft_assert(t, fp != NULL);
	ft_log_FILE(t, "", fp);
	DO_E(rc, setvbuf(fp, NULL, _IOFBF, 128), t, "%d");
	ft_assert(t, rc == 0);
	ft_log_FILE(t, "", fp);
	DO_E(rc, ftell(fp), t, "%d");
	ft_assert(t, rc == 0);

	/* Perform a first read of 16 bytes */
	DO_E(rc, fread(str, 1, 16, fp), t, "%d");
	ft_assert(t, rc == 16 && !memcmp(str, "The fread functi", 16));
	ft_log_FILE(t, "", fp);
	ft_assert(t, fp->bufdir == __FILE_BUF_READ);
	ft_assert(t, fp->fdpos == 128);
	ft_assert(t, fp->bufread == 128);
	ft_assert(t, fp->bufpos == 16);
	ft_assert(t, fp->eof == 0);
	ft_assert(t, feof(fp) == 0);

	/* Perform several reads that are longer than the buffer */
	DO_E(rc, fread(str, 1, 384, fp), t, "%d");
	ft_assert(t, rc == 384 && !memcmp(str, filler+16, 384));
	ft_log_FILE(t, "", fp);
	ft_assert(t, fp->bufdir == __FILE_BUF_READ);
	ft_assert(t, fp->fdpos == 512);
	ft_assert(t, fp->bufread == 128);
	ft_assert(t, fp->bufpos == 16);
	ft_assert(t, fp->eof == 0);
	ft_assert(t, feof(fp) == 0);

	/* Flush that buffer and check that we remain in place */
	DO_E(rc, fflush(fp), t, "%d");
	ft_assert(t, rc == 0);
	ft_log_FILE(t, "", fp);
	ft_assert(t, fp->bufdir == __FILE_BUF_READ);
	ft_assert(t, fp->fdpos == 400);
	ft_assert(t, fp->bufread == 0);
	ft_assert(t, fp->bufpos == 0);
	DO_E(rc, ftell(fp), t, "%d");
	ft_assert(t, rc == 400);

	/* Do another standard read that will reach end-of-file on the fd */
	DO_E(rc, fread(str, 1, 150, fp), t, "%d");
	ft_assert(t, rc == 150);
	ft_log_FILE(t, "", fp);
	ft_assert(t, fp->bufdir == __FILE_BUF_READ);
	ft_assert(t, fp->fdpos == 591);
	ft_assert(t, fp->bufread == 63);
	ft_assert(t, fp->bufpos == 22);
	ft_assert(t, fp->eof == 1);
	ft_assert(t, feof(fp) == 0);

	/* Do one last read that will not be entirely fulfilled */
	DO_E(rc, fread(str, 1, 64, fp), t, "%d");
	ft_assert(t, rc == 41);
	ft_log_FILE(t, "", fp);
	ft_assert(t, fp->bufdir == __FILE_BUF_READ);
	ft_assert(t, fp->fdpos == 591);
	ft_assert(t, fp->bufread == 0);
	ft_assert(t, fp->bufpos == 0);
	ft_assert(t, fp->eof == 1);
	ft_assert(t, feof(fp) == 1);
	DO_E(rc, ftell(fp), t, "%d");
	ft_assert(t, rc == 591);

	/* Rewind and move around */
	rewind(fp);
	ft_log(t, "rewind(fp)\n");
	DO_E(rc, ftell(fp), t, "%d");
	ft_assert(t, rc == 0);
	DO_E(rc, fseek(fp, -20, SEEK_END), t, "%d");
	ft_assert(t, rc == 0);
	DO_E(rc, ftell(fp), t, "%d");
	ft_assert(t, rc == 571);
	ft_assert(t, fp->eof == 0);
	ft_assert(t, feof(fp) == 0);

	/* Seek at end of file, the EOF flag should be cleared */
	DO_E(rc, fseek(fp, 0, SEEK_END), t, "%d");
	ft_assert(t, rc == 0);
	DO_E(rc, ftell(fp), t, "%d");
	ft_assert(t, rc == 591);
	ft_assert(t, fp->eof == 0);
	ft_assert(t, feof(fp) == 0);

	/* Attempt to read and get 0+EOF but no error */
	DO_E(rc, fread(str, 8, 1, fp), t, "%d");
	ft_assert(t, rc == 0);
	ft_assert(t, fp->eof == 1);
	ft_assert(t, feof(fp) == 1);

	/* Read into the buffer, then flush by seeking */
	DO_E(rc, fseek(fp, 0, SEEK_SET), t, "%d");
	ft_assert(t, rc == 0);
	DO_E(rc, fread(str, 1, 64, fp), t, "%d");
	ft_assert(t, rc == 64);
	ft_assert(t, !memcmp(str, filler, 64));
	ft_log_FILE(t, "", fp);
	ft_assert(t, fp->bufdir == __FILE_BUF_READ);
	ft_assert(t, fp->fdpos == 128);
	ft_assert(t, fp->bufread == 128);
	ft_assert(t, fp->bufpos == 64);
	ft_assert(t, fp->eof == 0);
	ft_assert(t, feof(fp) == 0);
	DO_E(rc, fseek(fp, 16, SEEK_SET), t, "%d");
	ft_assert(t, rc == 0);
	ft_log_FILE(t, "", fp);
	ft_assert(t, fp->fdpos == 16);
	ft_assert(t, fp->bufread == 0);
	ft_assert(t, fp->bufpos == 0);
	ft_assert(t, fp->eof == 0);
	ft_assert(t, feof(fp) == 0);
	DO_E(rc, fread(str, 1, 64, fp), t, "%d");
	ft_assert(t, rc == 64);
	ft_assert(t, !memcmp(str, filler+16, 64));
	ft_log_FILE(t, "", fp);
	ft_assert(t, fp->bufdir == __FILE_BUF_READ);
	ft_assert(t, fp->fdpos == 144);
	ft_assert(t, fp->bufread == 128);
	ft_assert(t, fp->bufpos == 64);
	ft_assert(t, fp->eof == 0);
	ft_assert(t, feof(fp) == 0);

	DO_E(rc, fclose(fp), t, "%d");
	ft_assert(t, rc == 0);

	free(str);
}

static void _ft_stdio_simple_read(ft_test *t)
{
	gint_world_switch(GINT_CALL(_ft_stdio_simple_read_switch, (void *)t));
}

ft_test ft_stdio_simple_read = {
	.name = "Simple file reading",
	.function = _ft_stdio_simple_read,
};