/*
 * Copyright 1999-2101 Alibaba Group.
 *
 * 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 com.alibaba.fastjson.serializer;

import java.io.IOException;
import java.lang.reflect.Type;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.util.IOUtils;

/**
 * @author wenshao<szujobs@hotmail.com>
 */
public class DateSerializer implements ObjectSerializer {

    public final static DateSerializer instance = new DateSerializer();

    public void write(JSONSerializer serializer, Object object, Object fieldName, Type fieldType) throws IOException {
        SerializeWriter out = serializer.getWriter();

        if (object == null) {
            out.writeNull();
            return;
        }

        if (out.isEnabled(SerializerFeature.WriteClassName)) {
            if (object.getClass() != fieldType) {
                if (object.getClass() == java.util.Date.class) {
                    out.write("new Date(");
                    out.writeLongAndChar(((Date) object).getTime(), ')');
                } else {
                    out.write('{');
                    out.writeFieldName(JSON.DEFAULT_TYPE_KEY);
                    serializer.write(object.getClass().getName());
                    out.write(',');
                    out.writeFieldName("val");
                    out.writeLong(((Date) object).getTime());
                    out.write('}');
                }
                return;
            }
        }
        
        Date date = (Date) object;
        
        if (out.isEnabled(SerializerFeature.WriteDateUseDateFormat)) {
            DateFormat format = serializer.getDateFormat();
            if (format == null) {
                format = new SimpleDateFormat(JSON.DEFFAULT_DATE_FORMAT);
            }
            String text = format.format(date);
            out.writeString(text);
            return;
        }

        long time = date.getTime();
        if (serializer.isEnabled(SerializerFeature.UseISO8601DateFormat)) {
            if (serializer.isEnabled(SerializerFeature.UseSingleQuotes)) {
                out.append('\'');
            } else {
                out.append('\"');
            }

            Calendar calendar = Calendar.getInstance();
            calendar.setTimeInMillis(time);

            int year = calendar.get(Calendar.YEAR);
            int month = calendar.get(Calendar.MONTH) + 1;
            int day = calendar.get(Calendar.DAY_OF_MONTH);
            int hour = calendar.get(Calendar.HOUR_OF_DAY);
            int minute = calendar.get(Calendar.MINUTE);
            int second = calendar.get(Calendar.SECOND);
            int millis = calendar.get(Calendar.MILLISECOND);

            char[] buf;
            if (millis != 0) {
                buf = "0000-00-00T00:00:00.000".toCharArray();
                IOUtils.getChars(millis, 23, buf);
                IOUtils.getChars(second, 19, buf);
                IOUtils.getChars(minute, 16, buf);
                IOUtils.getChars(hour, 13, buf);
                IOUtils.getChars(day, 10, buf);
                IOUtils.getChars(month, 7, buf);
                IOUtils.getChars(year, 4, buf);

            } else {
                if (second == 0 && minute == 0 && hour == 0) {
                    buf = "0000-00-00".toCharArray();
                    IOUtils.getChars(day, 10, buf);
                    IOUtils.getChars(month, 7, buf);
                    IOUtils.getChars(year, 4, buf);
                } else {
                    buf = "0000-00-00T00:00:00".toCharArray();
                    IOUtils.getChars(second, 19, buf);
                    IOUtils.getChars(minute, 16, buf);
                    IOUtils.getChars(hour, 13, buf);
                    IOUtils.getChars(day, 10, buf);
                    IOUtils.getChars(month, 7, buf);
                    IOUtils.getChars(year, 4, buf);
                }
            }

            out.write(buf);

            if (serializer.isEnabled(SerializerFeature.UseSingleQuotes)) {
                out.append('\'');
            } else {
                out.append('\"');
            }
        } else {
            out.writeLong(time);
        }
    }
}
