-- Prosody IM

-- Copyright (C) 2008-2010 Matthew Wild

-- Copyright (C) 2008-2010 Waqas Hussain

-- 

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

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

--

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

local httpstream_new = require "util.httpstream".new;

local listener;

local t_insert, t_concat = table.insert, table.concat;

local tonumber, tostring, pairs, ipairs, type = tonumber, tostring, pairs, ipairs, type;

local xpcall = xpcall;

local debug_traceback = debug.traceback;

local urlencode = function (s) return s and (s:gsub("%W", function (c) return ("%%%02x"):format(c:byte()); end)); end

local log = require "util.logger".init("httpserver");

local http_servers = {};

module "httpserver"

local default_handler;

local function send_response(request, response)

	-- Write status line

	local resp;

	if response.body or response.headers then

		local body = response.body and tostring(response.body);

		log("debug", "Sending response to %s", request.id);

		resp = { "HTTP/1.0 "..(response.status or "200 OK").."\r\n" };

		local h = response.headers;

		if h then

			for k, v in pairs(h) do

				t_insert(resp, k..": "..v.."\r\n");

			end

		end

		if body and not (h and h["Content-Length"]) then

			t_insert(resp, "Content-Length: "..#body.."\r\n");

		end

		t_insert(resp, "\r\n");

		if body and request.method ~= "HEAD" then

			t_insert(resp, body);

		end

		request.write(t_concat(resp));

	else

		-- Response we have is just a string (the body)

		log("debug", "Sending 200 response to %s", request.id or "<none>");

		local resp = "HTTP/1.0 200 OK\r\n"

			.. "Connection: close\r\n"

			.. "Content-Type: text/html\r\n"

			.. "Content-Length: "..#response.."\r\n"

			.. "\r\n"

			.. response;

		request.write(resp);

	end

	if not request.stayopen then

		request:destroy();

	end

end

local function call_callback(request, err)

	if request.handled then return; end

	request.handled = true;

	local callback = request.callback;

	if not callback and request.path then

		local path = request.url.path;

		local base = path:match("^/([^/?]+)");

		if not base then

			base = path:match("^http://[^/?]+/([^/?]+)");

		end

		callback = (request.server and request.server.handlers[base]) or default_handler;

	end

	if callback then

		local _callback = callback;

		function callback(method, body, request)

			local ok, result = xpcall(function() return _callback(method, body, request) end, debug_traceback);

			if ok then return result; end

			log("error", "Error in HTTP server handler: %s", result);

			-- TODO: When we support pipelining, request.destroyed

			-- won't be the right flag - we just want to see if there

			-- has been a response to this request yet.

			if not request.destroyed then

				return {

					status = "500 Internal Server Error";

					headers = { ["Content-Type"] = "text/plain" };

					body = "There was an error processing your request. See the error log for more details.";

				};

			end

		end

		if err then

			log("debug", "Request error: "..err);

			if not callback(nil, err, request) then

				destroy_request(request);

			end

			return;

		end

		local response = callback(request.method, request.body and t_concat(request.body), request);

		if response then

			if response == true and not request.destroyed then

				-- Keep connection open, we will reply later

				log("debug", "Request %s left open, on_destroy is %s", request.id, tostring(request.on_destroy));

			elseif response ~= true then

				-- Assume response

				send_response(request, response);

				destroy_request(request);

			end

		else

			log("debug", "Request handler provided no response, destroying request...");

			-- No response, close connection

			destroy_request(request);

		end

	end

end

local function request_reader(request, data, startpos)

	if not request.parser then

		local function success_cb(r)

			for k,v in pairs(r) do request[k] = v; end

			request.url = url_parse(request.path);

			request.url.path = request.url.path and request.url.path:gsub("%%(%x%x)", function(x) return x.char(tonumber(x, 16)) end);

			request.body = { request.body };

			call_callback(request);

		end

		local function error_cb(r)

			call_callback(request, r or "connection-closed");

			destroy_request(request);

		end

		request.parser = httpstream_new(success_cb, error_cb);

	end

	request.parser:feed(data);

end

-- The default handler for requests

default_handler = function (method, body, request)

	log("debug", method.." request for "..tostring(request.path) .. " on port "..request.handler:serverport());

	return { status = "404 Not Found",

			headers = { ["Content-Type"] = "text/html" },

			body = "<html><head><title>Page Not Found</title></head><body>Not here :(</body></html>" };

end

function new_request(handler)

	return { handler = handler, conn = handler,

			write = function (...) return handler:write(...); end, state = "request",

			server = http_servers[handler:serverport()],

			send = send_response,

			destroy = destroy_request,

			id = tostring{}:match("%x+$")

			 };

end

function destroy_request(request)

	log("debug", "Destroying request %s", request.id);

	if not request.destroyed then

		request.destroyed = true;

		if request.on_destroy then

			log("debug", "Request has destroy callback");

			request.on_destroy(request);

		else

			log("debug", "Request has no destroy callback");

		end

		request.handler:close()

		if request.conn then

			listener.ondisconnect(request.conn, "closed");

		end

	end

end

function new(params)

	local http_server = http_servers[params.port];

	if not http_server then

		http_server = { handlers = {} };

		http_servers[params.port] = http_server;

		-- We weren't already listening on this port, so start now

	end

	if params.base then

		http_server.handlers[params.base] = params.handler;

	end

end

function set_default_handler(handler)

	default_handler = handler;

end

function new_from_config(ports, handle_request, default_options)

	if type(handle_request) == "string" then -- COMPAT with old plugins

		log("warn", "Old syntax of httpserver.new_from_config being used to register %s", handle_request);

		handle_request, default_options = default_options, { base = handle_request };

	end

	ports = ports or {5280};

	for _, options in ipairs(ports) do

		local port = default_options.port or 5280;

		local base = default_options.base;

		local ssl = default_options.ssl or false;

		local interface = default_options.interface;

		if type(options) == "number" then

			port = options;

		elseif type(options) == "table" then

			port = options.port or port;

			base = options.path or base;

			ssl = options.ssl or ssl;

			interface = options.interface or interface;

		elseif type(options) == "string" then

			base = options;

		end

		if ssl then

			ssl.mode = "server";

			ssl.protocol = "sslv23";

			ssl.options = "no_sslv2";

		end

		new{ port = port, interface = interface,

			base = base, handler = handle_request,

			ssl = ssl, type = (ssl and "ssl") or "tcp" };

	end

end

_M.request_reader = request_reader;

_M.send_response = send_response;

_M.urlencode = urlencode;

return _M;