import { CLASSNAME_ATTRIBUTE } from "./Strings"

export abstract class DeserializerFactory {
    static entityClasses = {}

    static from(object: any) {
        if(!object){
            return
        }

        if(typeof object !== 'object'){ //definitely not a class object
            return object
        }
        
        if(Array.isArray(object)){
            return object.map(DeserializerFactory.from)
        }

        const clazz = DeserializerFactory.entityClasses[object[CLASSNAME_ATTRIBUTE]]
        delete object[CLASSNAME_ATTRIBUTE]

        if(!clazz){ //anonymous object or class not registered as @Serializable
            Object.keys(object).forEach(key => {
                object[key] = DeserializerFactory.from(object[key])
            })
            return object
        }

        const obj = new clazz()
        Object.keys(object).forEach(key => {
            obj[key] = DeserializerFactory.from(object[key])
        })
        return obj
    }

    

    static makeDeserializable(object: any){
        if(!object)
            return
        
        if(typeof object !== 'object')
            return object
        
        if(object.constructor.name === 'Object'){
            Object.keys(object).forEach(key => {
                object[key] = DeserializerFactory.makeDeserializable(object[key])
            })
            return object
        }

        object[CLASSNAME_ATTRIBUTE] = object.constructor.name
        Object.keys(object).forEach(key => {
            object[key] = DeserializerFactory.makeDeserializable(object[key])
        })

        return object
    }
}

export function Serializable(attr?: any) {
    return function _Serializable<T extends { new(...args: any[]): {} }>(clazz: T) {
        DeserializerFactory.entityClasses[clazz.name] = clazz
        
        return clazz
    }
}