/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2014, Digium, Inc.
 *
 * Kevin Harwell <kharwell@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

#include "asterisk.h"

#include "asterisk/astobj2.h"
#include "asterisk/strings.h"
#include "asterisk/uri.h"

#ifdef HAVE_URIPARSER
#include <uriparser/Uri.h>
#endif

/*! \brief Stores parsed uri information */
struct ast_uri {
	/*! scheme (e.g. http, https, ws, wss, etc...) */
	char *scheme;
	/*! username:password */
	char *user_info;
	/*! host name or address */
	char *host;
	/*! associated port */
	char *port;
	/*! path info following host[:port] */
	char *path;
	/*! query information */
	char *query;
	/*! storage for uri string */
	char uri[0];
};

/*!
 * \brief Construct a uri object with the given values.
 *
 * \note The size parameters [should] include room for the string terminator
 *       (strlen(<param>) + 1). For instance, if a scheme of 'http' is given
 *       then the 'scheme_size' should be equal to 5.
 */
static struct ast_uri *ast_uri_create_(
	const char *scheme, unsigned int scheme_size,
	const char *user_info, unsigned int user_info_size,
	const char *host, unsigned int host_size,
	const char *port, unsigned int port_size,
	const char *path, unsigned int path_size,
	const char *query, unsigned int query_size)
{
#define SET_VALUE(param, field, size) \
	do { if (param) { \
	     ast_copy_string(p, param, size); \
	     field = p; \
	     p += size;	} } while (0)

	char *p;
	struct ast_uri *res = ao2_alloc(
		sizeof(*res) + scheme_size + user_info_size + host_size +
		port_size + path_size + query_size, NULL);

	if (!res) {
		ast_log(LOG_ERROR, "Unable to create URI object\n");
		return NULL;
	}

	p = res->uri;
	SET_VALUE(scheme, res->scheme, scheme_size);
	SET_VALUE(user_info, res->user_info, user_info_size);
	SET_VALUE(host, res->host, host_size);
	SET_VALUE(port, res->port, port_size);
	SET_VALUE(path, res->path, path_size);
	SET_VALUE(query, res->query, query_size);
	return res;
}

struct ast_uri *ast_uri_create(const char *scheme, const char *user_info,
			       const char *host, const char *port,
			       const char *path, const char *query)
{
	return ast_uri_create_(
		scheme, scheme ? strlen(scheme) + 1 : 0,
		user_info, user_info ? strlen(user_info) + 1 : 0,
		host, host ? strlen(host) + 1 : 0,
		port, port ? strlen(port) + 1 : 0,
		path, path ? strlen(path) + 1 : 0,
		query, query ? strlen(query) + 1 : 0);
}

struct ast_uri *ast_uri_copy_replace(const struct ast_uri *uri, const char *scheme,
				     const char *user_info, const char *host,
				     const char *port, const char *path,
				     const char *query)
{
	return ast_uri_create(
		scheme ? scheme : uri->scheme,
		user_info ? user_info : uri->user_info,
		host ? host : uri->host,
		port ? port : uri->port,
		path ? path : uri->path,
		query ? query : uri->query);
}

const char *ast_uri_scheme(const struct ast_uri *uri)
{
	return uri->scheme;
}

const char *ast_uri_user_info(const struct ast_uri *uri)
{
	return uri->user_info;
}

const char *ast_uri_host(const struct ast_uri *uri)
{
	return uri->host;
}

const char *ast_uri_port(const struct ast_uri *uri)
{
	return uri->port;
}

const char *ast_uri_path(const struct ast_uri *uri)
{
	return uri->path;
}

const char *ast_uri_query(const struct ast_uri *uri)
{
	return uri->query;
}

int ast_uri_is_secure(const struct ast_uri *uri)
{
	return ast_strlen_zero(uri->scheme) ? 0 :
		*(uri->scheme + strlen(uri->scheme) - 1) == 's';
}

#ifdef HAVE_URIPARSER
struct ast_uri *ast_uri_parse(const char *uri)
{
	UriParserStateA state;
	UriUriA uria;
	struct ast_uri *res;
	unsigned int scheme_size, user_info_size, host_size;
	unsigned int port_size, path_size, query_size;
	const char *path_start, *path_end;

	state.uri = &uria;
	if (uriParseUriA(&state, uri) != URI_SUCCESS) {
		ast_log(LOG_ERROR, "Unable to parse URI %s\n", uri);
		uriFreeUriMembersA(&uria);
		return NULL;
	}

	scheme_size = uria.scheme.first ?
		uria.scheme.afterLast - uria.scheme.first + 1 : 0;
	user_info_size = uria.userInfo.first ?
		uria.userInfo.afterLast - uria.userInfo.first + 1 : 0;
	host_size = uria.hostText.first ?
		uria.hostText.afterLast - uria.hostText.first + 1 : 0;
	port_size = uria.portText.first ?
		uria.portText.afterLast - uria.portText.first + 1 : 0;

	path_start = uria.pathHead && uria.pathHead->text.first ?
		uria.pathHead->text.first : NULL;
	path_end = path_start ? uria.pathTail->text.afterLast : NULL;
	path_size = path_end ? path_end - path_start + 1 : 0;

	query_size = uria.query.first ?
		uria.query.afterLast - uria.query.first + 1 : 0;

	res = ast_uri_create_(uria.scheme.first, scheme_size,
			      uria.userInfo.first, user_info_size,
			      uria.hostText.first, host_size,
			      uria.portText.first, port_size,
			      path_start, path_size,
			      uria.query.first, query_size);
	uriFreeUriMembersA(&uria);
	return res;
}
#else
struct ast_uri *ast_uri_parse(const char *uri)
{
#define SET_VALUES(value) \
	value = uri; \
	size_##value = p - uri + 1; \
	uri = p + 1;

	const char *p, *scheme = NULL, *user_info = NULL, *host = NULL;
	const char *port = NULL, *path = NULL, *query = NULL;
	unsigned int size_scheme = 0, size_user_info = 0, size_host = 0;
	unsigned int size_port = 0, size_path = 0, size_query = 0;

	if ((p = strstr(uri, "://"))) {
		scheme = uri;
		size_scheme = p - uri + 1;
		uri = p + 3;
	}

	if ((p = strchr(uri, '@'))) {
		SET_VALUES(user_info);
	}

	if ((p = strchr(uri, ':'))) {
		SET_VALUES(host);
	}

	if ((p = strchr(uri, '/'))) {
		if (!host) {
			SET_VALUES(host);
		} else {
			SET_VALUES(port);
		}
	}

	if ((p = strchr(uri, '?'))) {
		query = p + 1;
		size_query = strlen(query) + 1;
	} else {
		p = uri + strlen(uri);
	}

	if (!host) {
		SET_VALUES(host);
	} else if (*(uri - 1) == ':') {
		SET_VALUES(port);
	} else if (*(uri - 1) == '/') {
		SET_VALUES(path);
	}

	return ast_uri_create_(scheme, size_scheme,
			       user_info, size_user_info,
			       host, size_host,
			       port, size_port,
			       path, size_path,
			       query, size_query);
}
#endif

static struct ast_uri *uri_parse_and_default(const char *uri, const char *scheme,
					     const char *port, const char *secure_port)
{
	struct ast_uri *res;
	int len = strlen(scheme);

	if (!strncmp(uri, scheme, len)) {
		res = ast_uri_parse(uri);
	} else {
		/* make room for <scheme>:// */
		char *with_scheme = ast_malloc(len + strlen(uri) + 4);
		if (!with_scheme) {
			ast_log(LOG_ERROR, "Unable to allocate uri '%s' with "
				"scheme '%s'", uri, scheme);
			return NULL;
		}

		/* safe - 'with_scheme' created with size equal to len of
		   scheme plus length of uri plus space for extra characters
		   '://' and terminator */
		sprintf(with_scheme, "%s://%s", scheme, uri);
		res = ast_uri_parse(with_scheme);
		ast_free(with_scheme);
	}

	if (res && ast_strlen_zero(ast_uri_port(res))) {
		/* default the port if not given */
		struct ast_uri *tmp = ast_uri_copy_replace(
			res, NULL, NULL, NULL,
			ast_uri_is_secure(res) ? secure_port : port,
			NULL, NULL);
		ao2_ref(res, -1);
		res = tmp;
	}
	return res;
}

struct ast_uri *ast_uri_parse_http(const char *uri)
{
	return uri_parse_and_default(uri, "http", "80", "443");
}

struct ast_uri *ast_uri_parse_websocket(const char *uri)
{
	return uri_parse_and_default(uri, "ws", "80", "443");
}

char *ast_uri_make_host_with_port(const struct ast_uri *uri)
{
	int host_size = ast_uri_host(uri) ?
		strlen(ast_uri_host(uri)) : 0;
	/* if there is a port +1 for the colon */
	int port_size = ast_uri_port(uri) ?
		strlen(ast_uri_port(uri)) + 1 : 0;
	char *res = ast_malloc(host_size + port_size + 1);

	if (!res) {
		return NULL;
	}

	memcpy(res, ast_uri_host(uri), host_size);

	if (ast_uri_port(uri)) {
		res[host_size] = ':';
		memcpy(res + host_size + 1,
		       ast_uri_port(uri), port_size - 1);
	}

	res[host_size + port_size] = '\0';
	return res;
}