/*
 * #%L
 * HAPI FHIR - Core Library
 * %%
 * Copyright (C) 2014 - 2023 Smile CDR, 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.
 * #L%
 */
package ca.uhn.fhir.model.primitive;

import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

import ca.uhn.fhir.model.api.TemporalPrecisionEnum;
import ca.uhn.fhir.model.api.annotation.DatatypeDef;
import ca.uhn.fhir.model.api.annotation.SimpleSetter;
import ca.uhn.fhir.parser.DataFormatException;

/**
 * Represents a FHIR instant datatype. Valid precisions values for this type are:
 * <ul>
 * <li>{@link TemporalPrecisionEnum#SECOND}
 * <li>{@link TemporalPrecisionEnum#MILLI}
 * </ul>
 */
@DatatypeDef(name = "instant")
public class InstantDt extends BaseDateTimeDt {

        /**
         * The default precision for this type
         */
        public static final TemporalPrecisionEnum DEFAULT_PRECISION = TemporalPrecisionEnum.MILLI;

        /**
         * Constructor which creates an InstantDt with <b>no timne value</b>. Note
         * that unlike the default constructor for the Java {@link Date} or
         * {@link Calendar} objects, this constructor does not initialize the object
         * with the current time.
         * 
         * @see #withCurrentTime() to create a new object that has been initialized
         *      with the current time.
         */
        public InstantDt() {
                super();
        }

        /**
         * Create a new DateTimeDt
         */
        public InstantDt(Calendar theCalendar) {
                super(theCalendar.getTime(), DEFAULT_PRECISION, theCalendar.getTimeZone());
        }

        /**
         * Create a new instance using the given date, precision level, and time zone
         * 
         * @throws DataFormatException
         *             If the specified precision is not allowed for this type
         */
        public InstantDt(Date theDate, TemporalPrecisionEnum thePrecision, TimeZone theTimezone) {
                super(theDate, thePrecision, theTimezone);
        }


        /**
         * Create a new DateTimeDt using an existing value. <b>Use this constructor with caution</b>,
         * as it may create more precision than warranted (since for example it is possible to pass in
         * a DateTime with only a year, and this constructor will convert to an InstantDt with 
         * milliseconds precision).
         */
        public InstantDt(BaseDateTimeDt theDateTime) {
                // Do not call super(foo) here, we don't want to trigger a DataFormatException
                setValue(theDateTime.getValue());
                setPrecision(DEFAULT_PRECISION);
                setTimeZone(theDateTime.getTimeZone());
        }

        /**
         * Create a new DateTimeDt with the given date/time and {@link TemporalPrecisionEnum#MILLI} precision
         */
        @SimpleSetter(suffix = "WithMillisPrecision")
        public InstantDt(@SimpleSetter.Parameter(name = "theDate") Date theDate) {
                super(theDate, DEFAULT_PRECISION, TimeZone.getDefault());
        }

        /**
         * Constructor which accepts a date value and a precision value. Valid
         * precisions values for this type are:
         * <ul>
         * <li>{@link TemporalPrecisionEnum#SECOND}
         * <li>{@link TemporalPrecisionEnum#MILLI}
         * </ul>
         */
        @SimpleSetter
        public InstantDt(@SimpleSetter.Parameter(name = "theDate") Date theDate, @SimpleSetter.Parameter(name = "thePrecision") TemporalPrecisionEnum thePrecision) {
                setValue(theDate);
                setPrecision(thePrecision);
                setTimeZone(TimeZone.getDefault());
        }

        /**
         * Create a new InstantDt from a string value
         * 
         * @param theString
         *            The string representation of the string. Must be in a valid
         *            format according to the FHIR specification
         * @throws DataFormatException
         */
        public InstantDt(String theString) {
                super(theString);
        }

        /**
         * Invokes {@link Date#after(Date)} on the contained Date against the given
         * date
         * 
         * @throws NullPointerException
         *             If the {@link #getValue() contained Date} is null
         */
        public boolean after(Date theDate) {
                return getValue().after(theDate);
        }

        /**
         * Invokes {@link Date#before(Date)} on the contained Date against the given
         * date
         * 
         * @throws NullPointerException
         *             If the {@link #getValue() contained Date} is null
         */
        public boolean before(Date theDate) {
                return getValue().before(theDate);
        }

        /**
         * Sets the value of this instant to the current time (from the system
         * clock) and the local/default timezone (as retrieved using
         * {@link TimeZone#getDefault()}. This TimeZone is generally obtained from
         * the underlying OS.
         */
        public void setToCurrentTimeInLocalTimeZone() {
                setValue(new Date());
                setTimeZone(TimeZone.getDefault());
        }

        @Override
        protected boolean isPrecisionAllowed(TemporalPrecisionEnum thePrecision) {
                switch (thePrecision) {
                case SECOND:
                case MILLI:
                        return true;
                default:
                        return false;
                }
        }

        /**
         * Factory method which creates a new InstantDt with millisecond precision and initializes it with the
         * current time and the system local timezone.
         */
        public static InstantDt withCurrentTime() {
                return new InstantDt(new Date(), TemporalPrecisionEnum.MILLI, TimeZone.getDefault());
        }

        /**
         * Returns the default precision for this datatype
         * 
         * @see #DEFAULT_PRECISION
         */
        @Override
        protected TemporalPrecisionEnum getDefaultPrecisionForDatatype() {
                return DEFAULT_PRECISION;
        }

}