--[[

HTTP server implementation for LuCI - helper class
(c) 2008 Freifunk Leipzig / Jo-Philipp Wich <xm@leipzig.freifunk.net>

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

$Id$

]]--

module("luci.httpd.server", package.seeall)


MAX_CLIENTS  = 15
READ_BUFSIZE = 1024


function error400( client, msg )
	client:send( "HTTP/1.0 400 Bad request\r\n" )
	client:send( "Content-Type: text/plain\r\n\r\n" )

	if msg then
		client:send( msg .. "\r\n" )
	end

	client:close()
end

function error503( client )
	client:send( "HTTP/1.0 503 Server unavailable\r\n" )
	client:send( "Content-Type: text/plain\r\n\r\n" )
	client:send( "There are too many clients connected, try again later\r\n" )
	client:close()
end


function client_handler(client)

	client:settimeout( 0 )

	-- Create LTN12 block source
	local block_source = function()

		coroutine.yield()

		local chunk, err, part = client:receive( READ_BUFSIZE )

		if chunk == nil and err == "timeout" then
			return part
		elseif chunk ~= nil then
			return chunk
		else
			return nil, err
		end

	end

	-- Create LTN12 line source
	local line_source = ltn12.source.simplify( function()

		coroutine.yield()

		local chunk, err, part = client:receive("*l")

		-- Line too long
		if chunk == nil and err ~= "timeout" then

			return nil, part
				and "Line exceeds maximum allowed length["..part.."]"
				or  "Unexpected EOF"

		-- Line ok
		else

			-- Strip trailing CR
			chunk = chunk:gsub("\r$","")

			-- We got end of headers, switch to dummy source
			if #chunk == 0 then
				return "", function()
					return nil
				end
			else
				return chunk, nil
			end
		end
	end )

	coroutine.yield(client)


	-- parse message
	local message, err = luci.http.protocol.parse_message_header( line_source )

	if message then
		local s, e = luci.http.protocol.parse_message_body( block_source, message )

		-- XXX: debug
		luci.util.dumptable( message )

		if not s and e then
			error400( client, e )
		end
	else
		error400( client, err )
	end

	-- send response
	error400( client, "Dummy response" )
end