package org.msh.etbm.db.entities;

import org.msh.etbm.commons.date.Period;

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


/**
 * @author Ricardo
 *         <p>
 *         Handles the weekly frequency of dispensing of medicines
 */
public class WeeklyFrequency {

    private int value;


    public WeeklyFrequency(int value) {
        super();
        this.value = value;
    }

    public WeeklyFrequency() {
        super();
    }

    /**
     * Set the week day dispensing information
     *
     * @param day - value between 1 and 7
     * @param val
     */
    public void setDay(int day, boolean val) {
        int n = (1 << (day - 1));

        if (val) {
            value |= n;
        } else {
            if ((value & n) != 0) {
                value ^= n;
            }
        }
    }

    /**
     * Returns if the day is set in the current date
     *
     * @param dt
     * @return true if the week day is set in the current day, otherwise returns false
     */
    public boolean isDateSet(Date dt) {
        Calendar c = Calendar.getInstance();
        c.setTime(dt);
        int day = c.get(Calendar.DAY_OF_WEEK);
        return getDay(day);
    }

    /**
     * Calculate the number of days selected in the frequency between two dates
     *
     * @param p the period to evaluate
     * @return
     */
    public int calcNumDays(Period p) {
        if (p.getIniDate().equals(p.getEndDate())) {
            Calendar c = Calendar.getInstance();
            c.setTime(p.getIniDate());
            int wd = c.get(Calendar.DAY_OF_WEEK);
            return getDay(wd) ? 1 : 0;
        }

        // get number of days between dates (+ 1 <= include the last day)
        int nd = p.getDays() + 1;

        int res;
        // number of days is bigger than a week
        if (nd > 7) {
            // calculate number of weeks
            int n = nd / 7;
            // calculate the number of days for the weeks
            res = n * getDaysInAWeek();

            if (nd % 7 == 0) {
                return res;
            }
        } else {
            res = 0;
        }

        Calendar c = Calendar.getInstance();
        c.setTime(p.getIniDate());
        int wd1 = c.get(Calendar.DAY_OF_WEEK);

        c.setTime(p.getEndDate());
        int wd2 = c.get(Calendar.DAY_OF_WEEK);

        // include days of the last week
        while (wd1 != wd2) {
            if (getDay(wd1)) {
                res++;
            }

            wd1++;
            if (wd1 > 7) {
                wd1 = 1;
            }
        }

        // adjust to include the last day in the check
        if (getDay(wd1)) {
            res++;
        }

        return res;
    }

    /**
     * Get the week day dispensing information
     *
     * @param day - value between 1 and 7
     * @return true - the week day is set to have dispensing
     */
    public boolean getDay(int day) {
        return ((value >> (day - 1)) & 1) != 0;
    }

    /**
     * Return the representation of the weekly scheme in a format n/7
     *
     * @return
     */
    public String getDisplayName() {
        int num = getDaysInAWeek();

        if (num == 0) {
            return "";
        } else {
            return Integer.toString(num) + "/7";
        }
    }

    /**
     * Return the number of days of dispensing in a week
     *
     * @return
     */
    public int getDaysInAWeek() {
        if (value == 0) {
            return 0;
        }

        int mask = 1;
        int num = 0;
        for (int i = 1; i <= 7; i++) {
            if ((value & mask) != 0) {
                num++;
            }
            mask *= 2;
        }
        return num;
    }

    public Boolean[] getWeekMask() {
        Boolean[] mask = new Boolean[7];
        for (int i = 1; i <= 7; i++) {
            mask[i - 1] = getDay(i);
        }

        return mask;
    }

    public void setWeekMask(Boolean[] vals) {
        int i = 1;
        for (Boolean b : vals) {
            if (b != null) {
                setDay(i, b);
            }
            i++;
        }
    }

    public int getValue() {
        return value;
    }

    public void setValue(int val) {
        value = val;
    }


    /* (non-Javadoc)
     * @see java.lang.Object#hashCode()
     */
    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + value;
        return result;
    }


    /* (non-Javadoc)
     * @see java.lang.Object#equals(java.lang.Object)
     */
    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }

        if (obj == null) {
            return false;
        }

        if (getClass() != obj.getClass()) {
            return false;
        }

        WeeklyFrequency other = (WeeklyFrequency) obj;

        if (value != other.value) {
            return false;
        }

        return true;
    }
}