import { Message } from '@node-ts/bus-messages'
import { HandlerRegistry } from '../handler'
import { Serializer } from './serializer'

/**
 * This a wrapper around the real serializer.
 * Unlike JsonSerializer, whose sole job is parsing data,
 * this class will do some plumbing work to look up the Handler Registry for
 * the message constructor.
 *
 * Normally, transports will use this instead of the real serializer.
 */
export class MessageSerializer {
  constructor(
    private readonly serializer: Serializer,
    private readonly handlerRegistry: HandlerRegistry
  ) {}

  serialize<MessageType extends Message>(message: MessageType): string {
    return this.serializer.serialize(message)
  }

  deserialize<MessageType extends Message>(
    serializedMessage: string
  ): MessageType {
    const naiveDeserializedMessage = JSON.parse(serializedMessage) as Message
    const messageType = this.handlerRegistry.getMessageConstructor(
      naiveDeserializedMessage.$name
    )

    return (
      !!messageType
        ? this.serializer.deserialize(serializedMessage, messageType)
        : naiveDeserializedMessage
    ) as MessageType
  }
}