package json

import (
	"encoding/json"

	"git.loafle.net/overflow/rpc-go/codec"
	"git.loafle.net/overflow/rpc-go/protocol"
)

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

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

// NewCustomServerCodec returns a new JSON Codec.
func NewCustomServerCodec(codecSelector codec.CodecSelector) protocol.ServerCodec {
	return &ServerCodec{
		codecSelector: codecSelector,
	}
}

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

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

func (sc *ServerCodec) NewRequest(messageType int, message []byte) (protocol.ServerRequestCodec, error) {
	buf, err := sc.codecSelector.Decode(messageType, message)
	if nil != err {
		return nil, err
	}
	return newServerRequestCodec(sc.codecSelector, 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{}) (messageType int, message []byte, err error) {
	params, err := convertParamsToStringArray(args)
	if nil != err {
		return 0, nil, err
	}

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

	buf, err := json.Marshal(res)
	if nil != err {
		return 0, nil, err
	}

	messageType, message, err = sc.codecSelector.Encode(buf)
	if nil != err {
		return 0, nil, err
	}

	return
}