require "jsonrpc/tcpsock"

JSONRPC = JSONRPC or {}

-- dumb hack: lua apparently can't manipulate arg tuples very effectively
-- and messing around with arg tables is even dumber than this
-- can we do this any better in 5.1?
local function result_call(cb, c, method, xid, ...)
  return cb(c, unpack(arg))
end

function JSONRPC.make_server(port, request_methods, notify_methods, conn_callback, disconn_callback)
  return TCP.make_server(port, 
    function(newconn, err) -- new connection
      -- connection from.. some host but i can't request the peer
      -- address because that isn't in the API.. blah
      if newconn then
        -- register a notify method
        function newconn:notify(...)
          --print('conn:notify: '..StrTable(arg))
          newconn:Send(json.encode{'notify', unpack(arg)}..'\n')
        end
        conn_callback(newconn)
      end
    end,
    function(c, line) -- receive line
      local ok,req = pcall(json.decode, line)
      if not ok or type(req) ~= "table" then
        print('Invalid JSON from '..tostring(c)..': '..req)
      elseif req[1] == 'notify' then
        local method = req[2]
        if notify_methods[method] then
          xpcall(function()
                 -- strip off 'notify' and method (instead of method and xid).. same result
                 result_call(notify_methods[method], c, unpack(req))
               end,
               function(err)
                 log.error("rpcserv notify"..StrTable(req)..":"..tostring(err))
               end)
        end
      else
        --print('JSONRPC from '..c.tcp:GetPeerName()..': '..StrTable(req))
        local method, reqid = unpack(req)
        if request_methods[method] then
          local result
          xpcall(function() 
                 c:Send(json.encode{'result', reqid, 
                    result_call(request_methods[method], 
                           c, unpack(req))}..'\n')
               end,
               function(err)
                 c:Send(json.encode{'error', reqid, err}..'\n')
               end)
        else
          c:Send(json.encode{'error', reqid, 'no such method'}..'\n')
        end
      end
    end,
    function(c) -- disconnect
      disconn_callback(c)
    end)
end