/*
 * The Rin Library – library "conformance" tests
 *
 * Copyright (C) 2015-2017 Gediminas Jakutis
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; version 2.1
 * of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

#include <unistd.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include "test.h"
#include "rin/diagnostic.h"

struct stdiocap {
	int pipefd[2];
	int origfd;
	int backupfd;
	FILE *pipe;
};

static int err_test(void);
static int warn_test(void);
static int fixme_test(void);
static int info_test(void);
static int prefix_test(void);
static int thread_test(void);
static int clean_test(void);
static struct stdiocap capture_stdio_start(FILE *stream);
static void capture_stdio_stop(struct stdiocap *cap);
static char *visible_newlines(const char * const in);
static int test_default_channels(const char * const in, const char * const expected, size_t i, int usearg, void (*func)(const char *, ...));

int diagnostic_test(char *testname)
{
	static const struct test tests[] = {
			{"err", err_test},
			{"warn", warn_test},
			{"fixme", fixme_test},
			{"info", info_test},
			{"prefix", prefix_test},
			{"thread", thread_test},
			{"clean", clean_test} };
	size_t i;

	for (i = 0; i < arrlen(tests); ++i) {
		if (!strcmp(testname, tests[i].name)) {
			return tests[i].testfunc();
		}
	}

	return EXIT_FAILURE;
}

static int err_test(void)
{
	size_t i;
	int usearg;
	int ret;

	static const char *in[] = {"", "test", "test number is %zu", "%zu tests ran"};
	static const char *expected[] = {"error:\n", "error:test\n", "error:test number is 3\n", "error:4 tests ran\n"};

	for (i = 0; i < arrlen(in); ++i) {
		usearg = i < (arrlen(in) / 2) ? 0 : 1;
	ret = test_default_channels(in[i], expected[i], i, usearg, rin_err);
	}

	return ret;
}

static int warn_test(void)
{
	return 77;
}

static int fixme_test(void)
{
	return 77;
}

static int info_test(void)
{
	return 77;
}

static int prefix_test(void)
{
	return 77;
}

static int thread_test(void)
{
	return 77;
}

static int clean_test(void)
{
	return 77;
}

static struct stdiocap capture_stdio_start(FILE *stream)
{
	struct stdiocap ret;

	ret.origfd = fileno(stream);
	ret.backupfd = dup(ret.origfd);

	if (pipe(ret.pipefd)) {
		close(ret.backupfd);
		ret.backupfd = -1;
		ret.origfd = -1;
		ret.pipefd[0] = -1;
		ret.pipefd[1] = -1;
		ret.pipe = NULL;
	}

	dup2(ret.pipefd[1], ret.origfd);
	ret.pipe = fdopen(ret.pipefd[0], "r");
	return ret;
}

static void capture_stdio_stop(struct stdiocap *cap)
{
	/* restore original fd to the stream */
	dup2(cap->backupfd, cap->origfd);
	close(cap->backupfd);
	close(cap->pipefd[1]);
	close(cap->pipefd[0]);

	/* close everything we opened and invalidate all the descriptors */
	fclose(cap->pipe);
	cap->backupfd = -1;
	cap->origfd = -1;
	cap->pipefd[0] = -1;
	cap->pipefd[1] = -1;
	cap->pipe = NULL;
}

static char *visible_newlines(const char * const in)
{
	char *ret;
	const char *newline;
	const char *readptr;
	char *writeptr;

	readptr = in;
	ret = malloc(strlen(readptr) * 2 + 1);
	writeptr = ret;
	newline = strchr(readptr, '\n');

	while (newline) {
		/* write chunk until the next newline */
		memcpy(writeptr, readptr, newline - readptr);
		writeptr += newline - readptr; /* advance writing position */
		readptr = newline;
		++readptr; /* skip the newline */
		/* toss in replacement */
		memcpy(writeptr, "\\n", 2);
		writeptr += 2;
		newline = strchr(readptr, '\n');
	}

	/* write all that remains */
	strcpy(writeptr, readptr);
	return ret;
}

static int test_default_channels(const char * const in, const char * const expected, size_t i, int usearg, void (*func)(const char *, ...))
{
	char buf[32] = {0};
	struct stdiocap cap;
	size_t len;
	int ret = 0;

	len = strlen(expected);
	++len;

	cap = capture_stdio_start(stderr);

	if (!cap.pipe) {
		ret = -1;
		goto fail;
	}

	if (usearg) {
		func(in, i + 1);
	} else {
		func(in);
	}

	if (!(fgets(buf, sizeof(buf) < len ? sizeof(buf) : len, cap.pipe))) {
		ret = 1;
		goto fail;
	}

fail:
	capture_stdio_stop(&cap);

	if (ret == -1) {
		ret = ok(1, "%s: unexpected test program failure on iteration %zu", __func__, i);
	} else {
		char *tmp[2];

		ret = strncmp(buf, expected, sizeof(buf) < len ? sizeof(buf) : len);

		tmp[0] = visible_newlines(buf);
		tmp[1] = visible_newlines(expected);

		ret = ok(ret, "%s: expected: \"%s\", got: \"%s\"", __func__, tmp[1], tmp[0]);

		free(tmp[0]);
		free(tmp[1]);
	}

	return ret;
}