BaseContactor.kt

abstract class BaseContactor<T>(val handler:BasePresenter<T>?) {
    private val interceptor = HttpLoggingInterceptor()
    private val retrofit: Retrofit
    private val client: OkHttpClient
    protected val api: Api

    init {
        interceptor.level = HttpLoggingInterceptor.Level.BODY
        client = OkHttpClient.Builder().addInterceptor(interceptor).build()

        retrofit = Retrofit.Builder()
                .baseUrl(Api.BASE_URL)
                .client(client)
                .addConverterFactory(GsonConverterFactory.create())
                .build()
        api = retrofit.create(Api::class.java)
    }

    protected val callback: Callback<T> = object: Callback<T> {
        override fun onFailure(call: Call<T>?, t: Throwable?) {
            handler?.onError(t?.message)
            handler?.showProgress(false)
        }

        override fun onResponse(call: Call<T>?, response: Response<T>?) {
            handler?.showProgress(false)
            if (response?.isSuccessful ?:false) {
                handler?.onSuccess(response?.body())
            } else {
                handler?.onError("code:${response?.code()} errorbody:${response?.errorBody()?.string()}")
            }
        }
    }

    abstract protected fun prepareCaller(): Call<T>

    fun execute() {
        handler?.showProgress(true)
        val call = prepareCaller()
        call.enqueue(callback)
    }
}