/*
 * JsonUtils.java
 *
 * Copyright (c) 2016 Auth0 (http://auth0.com)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

package com.auth0.android.lock.internal.configuration;

import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParseException;

import java.lang.reflect.Type;

abstract class GsonDeserializer<T> implements JsonDeserializer<T> {

    <U> U requiredValue(String name, Type type, JsonObject object, JsonDeserializationContext context) throws JsonParseException {
        U value = context.deserialize(object.get(name), type);
        if (value == null) {
            throw new JsonParseException(String.format("Missing required attribute %s", name));
        }
        return value;
    }

    void assertJsonObject(JsonElement jsonObject) throws JsonParseException {
        if (jsonObject.isJsonNull() || !jsonObject.isJsonObject()) {
            throw new JsonParseException("Received json is not a valid json object.");
        }
    }
}