package com.example.nyuscps.junk;

import android.util.Log;

/**
 * Created by nyuscps on 2/21/15.
 */



public class Date {

    /** Because of the keyword "static", one copy of this array
     * is shared by all the Date objects.
     * No matter how many Date objects are created,
     * there will always be exactly one copy of this array.
     * In fact, there will always be exactly one copy of this array
     * even if no Date objects are ever created.
     */
    private static int[] a = {
            0,	//dummy
            31,	//January
            29,	//February: can't distinguish between leap and non-leap
            31,	//March
            30,	//April
            31,	//May
            30,	//June
            31,	//July
            31,	//August
            30,	//September
            31,	//October
            30,	//November
            31	//December
    };

    //The three fields (internal organs) of a Date object.

    private int year;

    /** in the range 1 to 12 inclusive */
    private int month;

    /** in the range 1 to number of days in month inclusive */
    private int day;

    /**
     * The length of the current month.
     * This method will eventually be overridden by a smarter method
     * in a derived class.
     *
     * @return number of days in month to which this Date object belongs
     */
    private int length() {
        return a[month];
    }

    /**
     * Create a new Date object.
     * This method is a constructor for class Date.
     *
     * @param month in the range 1 to 12 inclusive
     * @param day in the range 1 to number of days in month inclusive
     * @param year can't be zero
     */
    public Date(int month, int day, int year) {
        this.year = year;	//two variables with the same name
        this.month = month;
        this.day = day;
    }

    public Date() {
        year = 1;
        month = 1;
        day = 1;
    }

    /**
     * Move this Date object one day into the future.
     * If already at the last possible date, do nothing.
     */
    public void next() {
        if (day < length()) {
            ++day;
            return;
        }

        day = 1;
        if (month < 12) {
            ++month;
            return;
        }

        month = 1;
        if (year < Integer.MAX_VALUE) {
            ++year;
            return;
        }

        //Roll back an unsuccessful change.
        //Don't leave this Date object in a half-changed state.
        day = 31;
        month = 12;
        Log.d("mytag", "Can't go beyond " + this + ".");
    }

    public void prev() {
        if (day > 1) {
            --day;  //means day = day - 1;
            return;
        }

        //Arrive here when day == 1.
        if (month > 1) {
            --month;
        } else {
            //Arrive here if month == 1
            month = 12;
            --year;
        }

        day = length();
    }

    /**
     * Move this Date object count days into the future.
     *
     * @param count the number of days
     */
    public void next(int count) {
        if (count >= 0) {
            for (int i = 0; i < count; ++i) {
                next();
            }
        } else {
            for (int i = 0; i > count; --i) {
                prev();
            }
        }
    }

    /*
    public void prev(int count) {

        for (int i = 0; i < count; ++i) {
            prev();
        }
    }
    */

    /**
     * Return a String showing the contents of this Date object.
     * @return a String in the format 12/31/2011
     */
    public String toString() {
        return month + "/" + day + "/" + year;

        //The above statement could have been written
        //return this.month + "/" + this.day + "/" + this.year;
        //but it doesn't have to be.
    }

}