-----------------------------------------------------------------------------
-- Xavante CGILua handler
--
-- Authors: Javier Guerra and Andre Carregal
-- Copyright (c) 2004-2007 Kepler Project
--
-- $Id: cgiluahandler.lua,v 1.24 2007/06/22 23:56:08 carregal Exp $
-----------------------------------------------------------------------------

requests = requests or {}

module ("xavante.cgiluahandler", package.seeall)

require "rings"

-------------------------------------------------------------------------------
-- Implements SAPI
-------------------------------------------------------------------------------
-- returns the correct argument selector for Lua 5.0 or 5.1
local function argument(n)
    if string.find (_VERSION, "Lua 5.0") then
        return "arg["..tostring(n).."]"
    else
        return "select("..tostring(n)..", ...)"
    end
end

local state_init = [[

local select = select or function (n, ...) return arg[n] end


local id_string = 'requests["' ..]]..argument(1)..[[ .. '"]'

local function set_api ()
	local SAPI = {
		Response = {},
		Request = {},
	}
	-- Headers
	SAPI.Response.contenttype = function (s)
		remotedostring(id_string .. '.res.headers["Content-Type"] = ]]..argument(1)..[[', s)
	end
	SAPI.Response.redirect = function (s)
		remotedostring(id_string .. '.res.headers["Location"] = ]]..argument(1)..[[', s)
	end
	SAPI.Response.header = function (h, v)
		remotedostring(id_string .. ".res:add_header (]]..argument(1)..[[, ]]..argument(2)..[[)", h, v)
	end
	-- Contents
	SAPI.Response.write = function (s)
		coroutine.yield("SEND_DATA", s)
	end
	SAPI.Response.errorlog = function (s) 
		remotedostring('io.stderr:write(]]..argument(1)..[[)', s)
	end
	-- Input POST data
	SAPI.Request.getpostdata = function (n)
		return coroutine.yield("RECEIVE", n)
	end
	-- Input general information
	SAPI.Request.servervariable = function (n)
		return select(2, remotedostring('return ' .. id_string .. ".req.cgivars[]]..argument(1)..[[]", n))
	end
	
	return SAPI
end

SAPI = set_api ()
if string.find (_VERSION, "Lua 5.0") and not _COMPAT51 then
    _, LUA_PATH = remotedostring("return package.path")
    require"compat-5.1"
else
    _, package.path = remotedostring("return package.path")
end

_, package.cpath = remotedostring("return package.cpath")
require"coxpcall"
pcall = copcall
xpcall = coxpcall

_, CGILUA_APPS = remotedostring("return CGILUA_APPS")

require"cgilua"
main_coro = coroutine.wrap(function () cgilua.main() end)

]]

local function set_cgivars (req, diskpath)
	
	req.cgivars = {
		SERVER_SOFTWARE = req.serversoftware,
		SERVER_NAME = req.parsed_url.host,
		GATEWAY_INTERFACE = "CGI/1.1",
		SERVER_PROTOCOL = "HTTP/1.1",
		SERVER_PORT = req.parsed_url.port,
		REQUEST_METHOD = req.cmd_mth,
		PATH_INFO = "/"..req.relpath,
		PATH_TRANSLATED = diskpath .. "/"..req.relpath,
		SCRIPT_NAME = req.parsed_url.path,
		QUERY_STRING = req.parsed_url.query,
		REMOTE_HOST = nil,
		REMOTE_ADDR = string.gsub (req.rawskt:getpeername (), ":%d*$", ""),
		AUTH_TYPE = nil,
		REMOTE_USER = nil,
		CONTENT_TYPE = req.headers ["content-type"],
		CONTENT_LENGTH = req.headers ["content-length"],
	}
	for n,v in pairs (req.headers) do
		req.cgivars ["HTTP_"..string.gsub (string.upper (n), "-", "_")] = v
	end
end

local function cgiluahandler (req, res, diskpath)
	requests[tostring(req)] = { req = req, res = res }	

	set_cgivars (req, diskpath)
	local new_state = rings.new()
	assert(new_state:dostring(state_init, tostring(req)))
	local coro_arg, status, op, arg
	repeat
		status, op, arg = new_state:dostring("return main_coro("..argument(1)..")", coro_arg)
        if not status then
            error(op)
        end
		if op == "SEND_DATA" then
			res:send_data(arg)
		elseif op == "RECEIVE" then
			coro_arg = req.socket:receive(arg)
		end
	until not op
	-- release resources
	new_state:close()
	requests[tostring(req)] = nil
end

-------------------------------------------------------------------------------
-- Returns the CGILua handler
-------------------------------------------------------------------------------
function makeHandler (diskpath)
	return function (req, res)
		return cgiluahandler (req, res, diskpath)
	end
end