/**
 * Copyright (c) 2014, University of Warsaw
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are permitted
 * provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this list of
 * conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other materials provided
 * with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package pl.edu.mimuw.cloudatlas.model;

import java.lang.IllegalArgumentException;
import java.text.ParseException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * A class representing duration in milliseconds. The duration can be negative. This is a simple wrapper of a Java
 * <code>Long</code> object.
 */
public class ValueDuration extends ValueSimple<Long> {
    public static class InvalidFormatException extends IllegalArgumentException {
    }

    /**
     * Regex pattern for duration strings.
     */
    private static final Pattern DURATION_PATTERN = Pattern.compile(
        "(?<sign>[+-])(?<days>\\d+) " +
        "(?<hours>[0-1][0-9]|2[0-3]):(?<minutes>[0-5][0-9]):(?<seconds>[0-5][0-9])." +
        "(?<milliseconds>[0-9]{3})"
    );

    /**
     * Constructs a new <code>ValueDuration</code> object wrapping the specified <code>value</code>.
     *
     * @param value the value to wrap
     */
    public ValueDuration(Long value) {
        super(value);
    }

    /* Kryo needs a no-args constructor */
    private ValueDuration() {
    }

    @Override
    public Type getType() {
        return TypePrimitive.DURATION;
    }

    @Override
    public Value getDefaultValue() {
        return new ValueDuration(0l);
    }

    /**
     * Constructs a new <code>ValueDuration</code> object from the specified amounts of different time units.
     *
     * @param seconds a number of full seconds
     * @param milliseconds a number of milliseconds (an absolute value does not have to be lower than 1000)
     */
    public ValueDuration(long seconds, long milliseconds) {
        this(seconds * 1000l + milliseconds);
    }

    /**
     * Constructs a new <code>ValueDuration</code> object from the specified amounts of different time units.
     *
     * @param minutes a number of full minutes
     * @param seconds a number of full seconds (an absolute value does not have to be lower than 60)
     * @param milliseconds a number of milliseconds (an absolute value does not have to be lower than 1000)
     */
    public ValueDuration(long minutes, long seconds, long milliseconds) {
        this(minutes * 60l + seconds, milliseconds);
    }

    /**
     * Constructs a new <code>ValueDuration</code> object from the specified amounts of different time units.
     *
     * @param hours a number of full hours
     * @param minutes a number of full minutes (an absolute value does not have to be lower than 60)
     * @param seconds a number of full seconds (an absolute value does not have to be lower than 60)
     * @param milliseconds a number of milliseconds (an absolute value does not have to be lower than 1000)
     */
    public ValueDuration(long hours, long minutes, long seconds, long milliseconds) {
        this(hours * 60l + minutes, seconds, milliseconds);
    }

    /**
     * Constructs a new <code>ValueDuration</code> object from the specified amounts of different time units.
     *
     * @param days a number of full days
     * @param hours a number of full hours (an absolute value does not have to be lower than 24)
     * @param minutes a number of full minutes (an absolute value does not have to be lower than 60)
     * @param seconds a number of full seconds (an absolute value does not have to be lower than 60)
     * @param milliseconds a number of milliseconds (an absolute value does not have to be lower than 1000)
     */
    public ValueDuration(long days, long hours, long minutes, long seconds, long milliseconds) {
        this(days * 24l + hours, minutes, seconds, milliseconds);
    }

    /**
     * Constructs a new <code>ValueDuration</code> object from its textual representation. The representation has
     * format: <code>sd hh:mm:ss.lll</code> where:
     * <ul>
     * <li><code>s</code> is a sign (<code>+</code> or <code>-</code>),</li>
     * <li><code>d</code> is a number of days,</li>
     * <li><code>hh</code> is a number of hours (between <code>00</code> and <code>23</code>),</li>
     * <li><code>mm</code> is a number of minutes (between <code>00</code> and <code>59</code>),</li>
     * <li><code>ss</code> is a number of seconds (between <code>00</code> and <code>59</code>),</li>
     * <li><code>lll</code> is a number of milliseconds (between <code>000</code> and <code>999</code>).</li>
     * </ul>
     * <p>
     * All fields are obligatory.
     *
     * @param value a textual representation of a duration
     * @throws IllegalArgumentException if <code>value</code> does not meet described rules
     */
    public ValueDuration(String value) {
        this(parseDuration(value));
    }

    private static long parseDuration(String value) {
        Matcher matcher = DURATION_PATTERN.matcher(value);
        if (!matcher.matches()) {
            throw new InvalidFormatException();
        }

        long result = parseLongGroup(matcher, "days");
        result *= 24;
        result += parseLongGroup(matcher, "hours");
        result *= 60;
        result += parseLongGroup(matcher, "minutes");
        result *= 60;
        result += parseLongGroup(matcher, "seconds");
        result *= 1000;
        result += parseLongGroup(matcher, "milliseconds");
        result *= matcher.group("sign").equals("+") ? 1 : -1;

        return result;
    }

    /**
     * @param matcher A regex matcher
     * @param group The name of a group matched by <code>matcher</code> that
     * should have captured a number.
     * @return The parsed number.
     */
    private static long parseLongGroup(Matcher matcher, String group) {
        return Long.parseLong(matcher.group(group));
    }

    @Override
    public ValueBoolean isLowerThan(Value value) {
        sameTypesOrThrow(value, Operation.COMPARE);
        if(isNull() || value.isNull())
            return new ValueBoolean(null);
        return new ValueBoolean(getValue() < ((ValueDuration)value).getValue());
    }

    @Override
    public ValueDuration addValue(Value value) {
        sameTypesOrThrow(value, Operation.ADD);
        if (isNull() || value.isNull()) {
            return new ValueDuration((Long) null);
        }

        return new ValueDuration(getValue() + ((ValueDuration)value).getValue());
    }

    @Override
    public ValueDuration subtract(Value value) {
        sameTypesOrThrow(value, Operation.SUBTRACT);
        if (isNull() || value.isNull())
            return new ValueDuration((Long) null);
        return new ValueDuration(getValue() - ((ValueDuration)value).getValue());
    }

    @Override
    public ValueDuration multiply(Value value) {
        if (!value.getType().isCompatible(TypePrimitive.INTEGER)) {
            throw new IncompatibleTypesException(getType(), value.getType(), Operation.MULTIPLY);
        }

        if (isNull() || value.isNull()) {
            return new ValueDuration((Long) null);
        }

        return new ValueDuration(getValue() * ((ValueInt)value).getValue());
    }

    @Override
    public Value divide(Value value) {
        if (!value.getType().isCompatible(TypePrimitive.INTEGER)) {
            throw new IncompatibleTypesException(getType(), value.getType(), Operation.MULTIPLY);
        }

        if (isNull() || value.isNull()) {
            return new ValueDuration((Long) null);
        }

        if (((ValueInt)value).getValue() == 0l) {
            throw new ArithmeticException("Division by zero.");
        }

        return new ValueDuration(getValue() / ((ValueInt)value).getValue());
    }

    @Override
    public ValueDuration modulo(Value value) {
        if (!value.getType().isCompatible(TypePrimitive.INTEGER)) {
            throw new IncompatibleTypesException(getType(), value.getType(), Operation.MULTIPLY);
        }

        if (isNull() || value.isNull()) {
            return new ValueDuration((Long) null);
        }

        if (((ValueInt)value).getValue() == 0l) {
            throw new ArithmeticException("Division by zero.");
        }

        return new ValueDuration(getValue() % ((ValueInt)value).getValue());
    }

    @Override
    public ValueDuration negate() {
        if(isNull()) {
            return new ValueDuration((Long) null);
        }

        return new ValueDuration(-getValue());
    }


    private String makeString() {
        long remainingUnits = getValue();
        boolean positive = remainingUnits >= 0;
        remainingUnits = positive ? remainingUnits : -remainingUnits;

        long milliseconds = remainingUnits % 1000;
        remainingUnits /= 1000;
        long seconds = remainingUnits % 60;
        remainingUnits /= 60;
        long minutes = remainingUnits % 60;
        remainingUnits /= 60;
        long hours = remainingUnits % 24;
        remainingUnits /= 24;
        long days = remainingUnits;

        return (positive ? "+" : "-") + Long.toString(days) + " " + Long.toString(hours)
            + ":" + Long.toString(minutes) + ":" + Long.toString(seconds) + "." +
            Long.toString(milliseconds);
    }

    @Override
    public Value convertTo(Type type) {
        switch(type.getPrimaryType()) {
            case STRING:
                return getValue() == null? ValueString.NULL_STRING : new ValueString(makeString());
            case DURATION:
                return this;
            default:
                throw new UnsupportedConversionException(getType(), type);
        }
    }
}