/*
 * Copyright (C) 2008 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package cn.emay.sdk.util.json.gson;

import java.lang.reflect.Type;
import java.sql.Timestamp;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.ParsePosition;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;

import cn.emay.sdk.util.json.gson.internal.bind.util.ISO8601Utils;

/**
 * This type adapter supports three subclasses of date: Date, Timestamp, and
 * java.sql.Date.
 *
 * @author Inderjeet Singh
 * @author Joel Leitch
 */
final class DefaultDateTypeAdapter implements JsonSerializer<Date>, JsonDeserializer<Date> {

	// TODO: migrate to streaming adapter

	private final DateFormat enUsFormat;
	private final DateFormat localFormat;

	DefaultDateTypeAdapter() {
		this(DateFormat.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT, Locale.US), DateFormat.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT));
	}

	DefaultDateTypeAdapter(String datePattern) {
		this(new SimpleDateFormat(datePattern, Locale.US), new SimpleDateFormat(datePattern));
	}

	DefaultDateTypeAdapter(int style) {
		this(DateFormat.getDateInstance(style, Locale.US), DateFormat.getDateInstance(style));
	}

	public DefaultDateTypeAdapter(int dateStyle, int timeStyle) {
		this(DateFormat.getDateTimeInstance(dateStyle, timeStyle, Locale.US), DateFormat.getDateTimeInstance(dateStyle, timeStyle));
	}

	DefaultDateTypeAdapter(DateFormat enUsFormat, DateFormat localFormat) {
		this.enUsFormat = enUsFormat;
		this.localFormat = localFormat;
	}

	// These methods need to be synchronized since JDK DateFormat classes are not
	// thread-safe
	// See issue 162
	@Override
	public JsonElement serialize(Date src, Type typeOfSrc, JsonSerializationContext context) {
		synchronized (localFormat) {
			String dateFormatAsString = enUsFormat.format(src);
			return new JsonPrimitive(dateFormatAsString);
		}
	}

	@Override
	public Date deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
		if (!(json instanceof JsonPrimitive)) {
			throw new JsonParseException("The date should be a string value");
		}
		Date date = deserializeToDate(json);
		if (typeOfT == Date.class) {
			return date;
		} else if (typeOfT == Timestamp.class) {
			return new Timestamp(date.getTime());
		} else if (typeOfT == java.sql.Date.class) {
			return new java.sql.Date(date.getTime());
		} else {
			throw new IllegalArgumentException(getClass() + " cannot deserialize to " + typeOfT);
		}
	}

	private Date deserializeToDate(JsonElement json) {
		synchronized (localFormat) {
			try {
				return localFormat.parse(json.getAsString());
			} catch (ParseException ignored) {
			}
			try {
				return enUsFormat.parse(json.getAsString());
			} catch (ParseException ignored) {
			}
			try {
				return ISO8601Utils.parse(json.getAsString(), new ParsePosition(0));
			} catch (ParseException e) {
				throw new JsonSyntaxException(json.getAsString(), e);
			}
		}
	}

	@Override
	public String toString() {
		StringBuilder sb = new StringBuilder();
		sb.append(DefaultDateTypeAdapter.class.getSimpleName());
		sb.append('(').append(localFormat.getClass().getSimpleName()).append(')');
		return sb.toString();
	}
}