/*
 * Copyright (c) 2016-2021 Free Software Foundation, Inc.
 *
 * This file is part of libwget.
 *
 * Libwget 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, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Libwget 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 libwget.  If not, see <https://www.gnu.org/licenses/>.
 *
 *
 * Demo how to create a diagram from a text using www.websequencediagrams.com.
 * Using high-level API.
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wget.h>

int main(int argc WGET_GCC_UNUSED, const char *const *argv WGET_GCC_UNUSED)
{
	wget_http_connection *conn = NULL;
	wget_http_response *resp;

	// set up libwget global configuration
	wget_global_init(
		// WGET_DEBUG_STREAM, stderr,
		WGET_ERROR_STREAM, stderr,
		WGET_INFO_STREAM, stdout,
		0);

	// This is the text that we want to convert into a GFX
	const char *text = "alice->bob: authentication request\nbob-->alice: response";
	const char *style = "qsd";
	wget_buffer *url = wget_buffer_alloc(128);
	wget_buffer *body = wget_buffer_alloc(128);


	wget_buffer_strcpy(body, "message=");
	wget_iri_escape_query(text, body);
	wget_buffer_printf_append(body, "&style=%s&apiVersion=1", style);

	resp = wget_http_get(
		WGET_HTTP_URL, "https://www.websequencediagrams.com",
		WGET_HTTP_SCHEME, "POST",
		WGET_HTTP_HEADER_ADD, "Content-Type", "application/x-www-form-urlencoded",
		WGET_HTTP_BODY, body->data, body->length,
		WGET_HTTP_CONNECTION_PTR, &conn,
		0);

	if (resp) {
		// wget_info_printf("answer=%s\n", resp->body->data);

		// extract image URL using a hack. Using a JSON parser would be correct.
		const char *p, *e;
		if (!(p = strstr(resp->body->data, "\"img\": \"")))
				goto out;
		if (!(e = strchr(p + 8, '\"')))
			goto out;

		p += 8;
		wget_buffer_printf(url, "https://www.websequencediagrams.com/%.*s", (int) (e - p), p);

		// free the response
		wget_http_free_response(&resp);

		resp = wget_http_get(
			WGET_HTTP_URL, url->data,
			WGET_HTTP_BODY_SAVEAS, "out.png",
			0);

		if (resp)
			wget_info_printf("Saved out.png\n");
	}

out:
	wget_http_free_response(&resp);
	wget_http_close(&conn);
	wget_buffer_free(&body);
	wget_buffer_free(&url);

	// free resources - needed for valgrind testing
	wget_global_deinit();

	return 0;
}
