package json

import (
	"encoding/json"

	"git.loafle.net/commons/rpc-go/protocol"
)

var null = json.RawMessage([]byte("null"))

// ----------------------------------------------------------------------------
// Codec
// ----------------------------------------------------------------------------

// NewServerCodec returns a new JSON Codec.
func NewServerCodec() protocol.ServerCodec {
	return &ServerCodec{}
}

// ServerCodec creates a ServerRequestCodec to process each request.
type ServerCodec struct {
}

func (sc *ServerCodec) NewRequest(buf []byte) (protocol.ServerRequestCodec, error) {
	return newServerRequestCodec(buf)
}

func (sc *ServerCodec) NewRequestWithString(method string, params []string, id interface{}) (protocol.ServerRequestCodec, error) {
	req := &clientRequest{
		Version: Version,
		Method:  method,
		Params:  params,
		ID:      id,
	}

	buf, err := json.Marshal(req)
	if nil != err {
		return nil, err
	}

	return sc.NewRequest(buf)
}

func (sc *ServerCodec) NewNotification(method string, args []interface{}) ([]byte, error) {
	params, err := convertParamsToStringArray(args)
	if nil != err {
		return nil, err
	}

	noti := &serverNotification{Method: method, Params: params}
	res := &serverResponse{Version: Version, Result: noti}

	return json.Marshal(res)
}