void APIServer::serve_instances_unregister(Server *server, Server::session *session, struct mg_connection *conn, struct http_message *hm) {

	std::string uri(hm->uri.p, hm->uri.len);

	std::string instance = uri.substr(uri.rfind("/") + 1);

	UserInfo info;

	m_storage->getUser(session->user, info);

	std::string username = "";

	int type = (int) TYPE_STRING;

	m_storage->getUserSetting(info.id, instance, type, username);

	if (!username.empty()) {

		std::string response = server->send_command(instance, "unregister " + username);

		if (!response.empty()) {

			username = "";

			m_storage->updateUserSetting(info.id, instance, username);

			send_ack(conn, false, response);

		}

		else {

			send_ack(conn, true, "Unknown error.");

		}

	}

	else {

		send_ack(conn, true, "You are not registered to this Spectrum 2 instance.");

	}

}

void APIServer::serve_instances_register_form(Server *server, Server::session *session, struct mg_connection *conn, struct http_message *hm) {

	std::string uri(hm->uri.p, hm->uri.len);

	std::string instance = uri.substr(uri.rfind("/") + 1);

	std::string response = server->send_command(instance, "registration_fields");

	std::vector<std::string> fields;

	boost::split(fields, response, boost::is_any_of("\n"));

	if (fields.size() < 3) {

		fields.clear();

		fields.push_back("Jabber ID");

		fields.push_back("3rd-party network username");

		fields.push_back("3rd-party network password");

	}

	Document json;

	json.SetObject();

	json.AddMember("error", 0, json.GetAllocator());

	json.AddMember("username_label", fields[0].c_str(), json.GetAllocator());

	json.AddMember("legacy_username_label", fields[1].c_str(), json.GetAllocator());

	json.AddMember("password_label", fields[2].c_str(), json.GetAllocator());

	send_json(conn, json);

}

	else if (has_prefix(&hm->uri, "/api/v1/instances/unregister/")) {

		serve_instances_stop(server, sess, conn, hm);

	}

	else if (has_prefix(&hm->uri, "/api/v1/instances/register_form/")) {

		serve_instances_register_form(server, sess, conn, hm);

	}

		void serve_instances_unregister(Server *server, Server::session *sess, struct mg_connection *conn, struct http_message *hm);

		void serve_instances_register_form(Server *server, Server::session *sess, struct mg_connection *conn, struct http_message *hm);

<!--#include virtual="/header.html" -->

<h2>Register Spectrum 2 instance</h2>

<form action="/api/v1/instances/register" class="basic-grey" method="POST"> 

<h1>Register Spectrum 2 instance 

	<span id="description"></span> 

</h1> 

<label> 

	<span id="jid_desc"></span> 

	<input type="text" id="jid" name="jid" placeholder=""></textarea> 

</label> 

<label> 

	<span id="uin_desc"></span> 

	<input type="text" id="uin" name="uin" placeholder=""></textarea> 

</label> 

<label><span id="password_desc"></span> 

	<input type="password" id="password" name="password" placeholder=""></textarea> 

</label> 

<label> 

	<span>&nbsp;</span> 

	<input type="submit" class="button" value="Register" />

</label> 

<input type="hidden" name="instance" id="instance" value=""></input> 

</form><br/>

<script type="text/javascript">

$(function() {

	fill_instances_register_form();

});

</script>

<!--#include virtual="/footer.html" -->

			var row = '<tr>'

			row += '<td>' + instance.name + '</td>'

			row += '<td>' + instance.status + '</td>'

			if (command == 'register') {

				row += '<td><a class="button_command" href="/instances/register.shtml?id=' + instance.id + '">' + command + '</a>' + '</td></tr>';

				$("#main_result  > tbody:last-child").append(row);

			}

			else {

				row += '<td><a class="button_command" href="/api/v1/instances/' + command + '/' + instance.id + '">' + command + '</a>' + '</td></tr>';

				$(".button_command").click(function(e) {

					e.preventDefault();

					$(this).parent().empty().progressbar( {value: false} ).css('height', '1em');

					var url = $(this).attr('href');

					$.get(url, function(data) {

						show_instances();

					});

				})

			}

function getQueryParams(qs) {

	qs = qs.split('+').join(' ');

	var params = {},

		tokens,

		re = /[?&]?([^=]+)=([^&]*)/g;

	while (tokens = re.exec(qs)) {

		params[decodeURIComponent(tokens[1])] = decodeURIComponent(tokens[2]);

	}

	return params;

}

function fill_instances_register_form() {

	var query = getQueryParams(document.location.search);

	$("#instance").attr("value", query.id);

	$.get("/api/v1/instances/register_form/" + query.id, function(data) {

		$("#jid_desc").html(data.username_label + ":");

		$("#uin_desc").html(data.legacy_username_label + ":");

		$("#password_desc").html(data.password_label + ":");

		$("#jid").attr("placeholder", data.username_label);

		$("#uin").attr("placeholder", data.legacy_username_label);

		$("#password").attr("placeholder", data.password_label);

	});

}