package json

import (
	"encoding/json"
	"fmt"
	"sync"

	"git.loafle.net/commons_go/rpc/protocol"
)

// ----------------------------------------------------------------------------
// ClientCodecNotify
// ----------------------------------------------------------------------------

// newCodecRequest returns a new ClientCodecNotify.
func newClientCodecNotify(raw json.RawMessage) (protocol.ClientCodecNotify, error) {
	// Decode the request body and check if RPC method is valid.
	ccn := retainClientCodecNotify()
	err := json.Unmarshal(raw, &ccn.notify)
	if err != nil {
		releaseClientCodecNotify(ccn)
		return nil, err
	}
	if "" == ccn.notify.Method {
		releaseClientCodecNotify(ccn)
		return nil, fmt.Errorf("This is not ClientNotify")
	}

	if ccn.notify.Version != Version {
		ccn.err = &Error{
			Code:    E_INVALID_REQ,
			Message: "jsonrpc must be " + Version,
			Data:    ccn.notify,
		}
	}

	return ccn, nil
}

// ClientCodecNotify decodes and encodes a single notification.
type ClientCodecNotify struct {
	notify clientNotify
	err    error
}

func (ccn *ClientCodecNotify) Method() string {
	return ccn.notify.Method
}

func (ccn *ClientCodecNotify) ReadParams(args []interface{}) error {
	if ccn.err == nil && ccn.notify.Params != nil {
		// Note: if scr.request.Params is nil it's not an error, it's an optional member.
		// JSON params structured object. Unmarshal to the args object.
		if err := json.Unmarshal(*ccn.notify.Params, &args); err != nil {
			ccn.err = &Error{
				Code:    E_INVALID_REQ,
				Message: err.Error(),
				Data:    ccn.notify.Params,
			}
		}
	}
	return ccn.err
}

func (ccn *ClientCodecNotify) Complete() {
	releaseClientCodecNotify(ccn)
}

var clientCodecNotifyPool sync.Pool

func retainClientCodecNotify() *ClientCodecNotify {
	v := clientCodecNotifyPool.Get()
	if v == nil {
		return &ClientCodecNotify{}
	}
	return v.(*ClientCodecNotify)
}

func releaseClientCodecNotify(ccn *ClientCodecNotify) {
	ccn.notify.Version = ""
	ccn.notify.Method = ""
	ccn.notify.Params = nil

	clientCodecNotifyPool.Put(ccn)
}