-- Prosody IM

-- Copyright (C) 2008-2012 Matthew Wild

-- Copyright (C) 2008-2012 Waqas Hussain

--

-- This project is MIT/X11 licensed. Please see the

-- COPYING file in the source package for more information.

--

module:set_global();

module:depends("http_errors");

local portmanager = require "core.portmanager";

local moduleapi = require "core.moduleapi";

local url_parse = require "socket.url".parse;

local url_build = require "socket.url".build;

local server = require "net.http.server";

server.set_default_host(module:get_option_string("http_default_host"));

server.set_option("body_size_limit", module:get_option_number("http_max_content_size"));

server.set_option("buffer_size_limit", module:get_option_number("http_max_buffer_size"));

local function normalize_path(path)

	if path:sub(-1,-1) == "/" then path = path:sub(1, -2); end

	if path:sub(1,1) ~= "/" then path = "/"..path; end

	return path;

end

local function get_http_event(host, app_path, key)

	local method, path = key:match("^(%S+)%s+(.+)$");

	if not method then -- No path specified, default to "" (base path)

		method, path = key, "";

	end

	if method:sub(1,1) == "/" then

		return nil;

	end

	if app_path == "/" and path:sub(1,1) == "/" then

		app_path = "";

	end

end

local function get_base_path(host_module, app_name, default_app_path)

	return (normalize_path(host_module:get_option("http_paths", {})[app_name] -- Host

		or module:get_option("http_paths", {})[app_name] -- Global

		or default_app_path)) -- Default

		:gsub("%$(%w+)", { host = host_module.host });

end

local function redir_handler(event)

	event.response.headers.location = event.request.path.."/";

	if event.request.url.query then

		event.response.headers.location = event.response.headers.location .. "?" .. event.request.url.query

	end

	return 301;

end

local ports_by_scheme = { http = 80, https = 443, };

-- Helper to deduce a module's external URL

function moduleapi.http_url(module, app_name, default_path)

	app_name = app_name or (module.name:gsub("^http_", ""));

	local external_url = url_parse(module:get_option_string("http_external_url")) or {};

	if external_url.scheme and external_url.port == nil then

		external_url.port = ports_by_scheme[external_url.scheme];

	end

	local services = portmanager.get_active_services();

	local http_services = services:get("https") or services:get("http") or {};

	for interface, ports in pairs(http_services) do -- luacheck: ignore 213/interface

		for port, service in pairs(ports) do -- luacheck: ignore 512

			local url = {

				scheme = (external_url.scheme or service[1].service.name);

				host = (external_url.host or module:get_option_string("http_host", module.host));

				port = tonumber(external_url.port) or port or 80;

				path = normalize_path(external_url.path or "/")..

					(get_base_path(module, app_name, default_path or "/"..app_name):sub(2));

			}

			if ports_by_scheme[url.scheme] == url.port then url.port = nil end

			return url_build(url);

		end

	end

	module:log("warn", "No http ports enabled, can't generate an external URL");

	return "http://disabled.invalid/";

end

function module.add_host(module)

	local host = module:get_option_string("http_host", module.host);

	local apps = {};

	module.environment.apps = apps;

	local function http_app_added(event)

		local app_name = event.item.name;

		local default_app_path = event.item.default_path or "/"..app_name;

		local app_path = get_base_path(module, app_name, default_app_path);

		if not app_name then

			-- TODO: Link to docs

			module:log("error", "HTTP app has no 'name', add one or use module:provides('http', app)");

			return;

		end

		apps[app_name] = apps[app_name] or {};

		local app_handlers = apps[app_name];

		for key, handler in pairs(event.item.route or {}) do

			local event_name = get_http_event(host, app_path, key);

			if event_name then

				if type(handler) ~= "function" then

					local data = handler;

					handler = function () return data; end

				elseif event_name:sub(-2, -1) == "/*" then

					local base_path_len = #event_name:match("/.+$");

					local _handler = handler;

					handler = function (_event)

						local path = _event.request.path:sub(base_path_len);

						return _handler(_event, path);

					end;

					module:hook_object_event(server, event_name:sub(1, -3), redir_handler, -1);

				elseif event_name:sub(-1, -1) == "/" then

					module:hook_object_event(server, event_name:sub(1, -2), redir_handler, -1);

				end

				if not app_handlers[event_name] then

					app_handlers[event_name] = handler;

					module:hook_object_event(server, event_name, handler);

				else

					module:log("warn", "App %s added handler twice for '%s', ignoring", app_name, event_name);

				end

			else

				module:log("error", "Invalid route in %s, %q. See https://prosody.im/doc/developers/http#routes", app_name, key);

			end

		end

		local services = portmanager.get_active_services();

		if services:get("https") or services:get("http") then

			module:log("debug", "Serving '%s' at %s", app_name, module:http_url(app_name, app_path));

		else

			module:log("warn", "Not listening on any ports, '%s' will be unreachable", app_name);

		end

	end

	local function http_app_removed(event)

		local app_handlers = apps[event.item.name];

		apps[event.item.name] = nil;

		for event_name, handler in pairs(app_handlers) do

			module:unhook_object_event(server, event_name, handler);

		end

	end

	module:handle_items("http-provider", http_app_added, http_app_removed);

	server.add_host(host);

	function module.unload()

		server.remove_host(host);

	end

end

local trusted_proxies = module:get_option_set("trusted_proxies", { "127.0.0.1", "::1" })._items;

local function get_ip_from_request(request)

	local ip = request.conn:ip();

	local forwarded_for = request.headers.x_forwarded_for;

	if forwarded_for then

		forwarded_for = forwarded_for..", "..ip;

		for forwarded_ip in forwarded_for:gmatch("[^%s,]+") do

			if not trusted_proxies[forwarded_ip] then

				ip = forwarded_ip;

			end

		end

	end

	return ip;

end

module:wrap_object_event(server._events, false, function (handlers, event_name, event_data)

	local request = event_data.request;

	if request then

		-- Not included in eg http-error events

		request.ip = get_ip_from_request(request);

	end

	local ret = handlers(event_name, event_data);

	if ret ~= nil then

		return ret;

	end

	local host = (request.headers.host or ""):match("[^:]+");

	local host_event = request.method.." "..host..request.path:match("[^?]*");

	return handlers(host_event, event_data);

end);

module:provides("net", {

	name = "http";

	listener = server.listener;

	default_port = 5280;

	multiplex = {

		pattern = "^[A-Z]";

	};

});

module:provides("net", {

	name = "https";

	listener = server.listener;

	default_port = 5281;

	encryption = "ssl";

	ssl_config = {

		verify = "none";

	};

	multiplex = {

		pattern = "^[A-Z]";

	};

});