Original Fidesmo Result JsonSerializer

ResultSerializer.kt

package com.fidesmo.devicemanager.helpers

import com.google.gson.*
import com.google.gson.internal.LinkedTreeMap
import java.lang.reflect.ParameterizedType
import java.lang.reflect.Type
import java.lang.reflect.WildcardType

class ResultSerializer : JsonSerializer<Result<*, *>>, JsonDeserializer<Result<*, *>> {

    private val gson: Gson = Gson()

    override fun serialize(src: Result<*, *>?, typeOfSrc: Type?, context: JsonSerializationContext?): JsonElement? {
        return when (src) {
            is Result.Loading ->  context?.serialize("")
            is Result.Err -> context?.serialize("")
            is Result.Ok -> {
                val parameterizedType = typeOfSrc as ParameterizedType
                return context?.serialize(src.value, parameterizedType.actualTypeArguments[0])
            }
            null -> null
        }
    }

    override fun deserialize(json: JsonElement?, typeOfT: Type?, context: JsonDeserializationContext?): Result<*, *>? {
        return when {
            json?.isJsonObject == true -> {
                val parameterizedType = typeOfT as ParameterizedType
                return Result.ok(context?.deserialize<Any>(json, parameterizedType.actualTypeArguments[0])!!)
            }
            json?.isJsonArray == true -> {
                val parameterizedType = typeOfT as ParameterizedType
                if (parameterizedType.actualTypeArguments[0] is WildcardType) {
                    val internalListType = (parameterizedType.actualTypeArguments[0] as WildcardType).upperBounds[0] as ParameterizedType
                    val arr = context?.deserialize<Any>(json, parameterizedType.actualTypeArguments[0]) as ArrayList<*>
                    val result = arr.map { linkedTreeMap ->
                        val jsonElement = gson.toJsonTree(linkedTreeMap as LinkedTreeMap<*, *>).asJsonObject
                        return@map context.deserialize<Any>(jsonElement, internalListType.actualTypeArguments[0])
                    }
                    return Result.ok(result)
                } else {
                    return Result.ok(context?.deserialize<Any>(json, parameterizedType.actualTypeArguments[0])!!)
                }
            }
            else -> Result.Loading
        }
    }
}