<?php
/**
 * Part of bdrem
 *
 * PHP version 5
 *
 * @category  Tools
 * @package   Bdrem
 * @author    Christian Weiske <cweiske@cweiske.de>
 * @copyright 2014 Christian Weiske
 * @license   http://www.gnu.org/licenses/agpl.html GNU AGPL v3
 * @link      http://cweiske.de/bdrem.htm
 */
namespace bdrem;

/**
 * Event model with title, type and date.
 * Contains calculation methods
 *
 * @category  Tools
 * @package   Bdrem
 * @author    Christian Weiske <cweiske@cweiske.de>
 * @copyright 2014 Christian Weiske
 * @license   http://www.gnu.org/licenses/agpl.html GNU AGPL v3
 * @version   Release: @package_version@
 * @link      http://cweiske.de/bdrem.htm
 */
class Event
{
    /**
     * Title of the event or name of the person that has the event
     * @var string
     */
    public $title;

    /**
     * Type of the event, e.g. "birthday"
     * @var string
     */
    public $type;

    /**
     * Date of the event.
     * ???? as year is allowed
     *
     * @var string YYYY-MM-DD
     */
    public $date;

    /**
     * Reference date against which $age and $days are calculated
     * (often today)
     *
     * @var string YYYY-MM-DD
     */
    public $refDate;

    /**
     * "Localized" $date used for calculations against $refDate.
     * Month and day are the same as in $date, year is near $refDate's year.
     *
     * @var string YYYY-MM-DD
     */
    public $localDate;

    /**
     * Which repetition this is
     *
     * @var integer
     */
    public $age;

    /**
     * Number of days until the event (positive) or since the event (negative)
     *
     * @var integer
     */
    public $days;


    /**
     * Set event data
     *
     * @param string $title Name of person the event relates to
     * @param string $type  Type of the event (e.g. "birthday")
     * @param string $date  Date of the event in format YYYY-MM-DD
     */
    public function __construct($title = null, $type = null, $date = null)
    {
        $this->title = $title;
        $this->type  = $type;
        $this->date  = $date;
    }

    /**
     * Checks if the event's date is within the given date.
     * Also calculates the age and days since the event.
     *
     * @param string  $strDate       Date, YYYY-MM-DD
     * @param integer $nDaysPrevious Include number of days before $strDate
     * @param integer $nDaysNext     Include number of days after $strDate
     *
     * @return boolean True if the event's date is within the given range
     */
    public function isWithin($strDate, $nDaysPrevious, $nDaysNext)
    {
        $this->refDate = $strDate;
        list($rYear, $rMonth, $rDay) = explode('-', $strDate);
        list($eYear, $eMonth, $eDay) = explode('-', $this->date);

        if ($rMonth == $eMonth && $rDay == $eDay) {
            $this->localDate = $strDate;
            $this->days = 0;
            if ($eYear == '????') {
                $this->age = null;
            } else {
                $this->age = $rYear - $eYear;
            }
            return true;
        }

        $yearOffset = 0;
        if ($eMonth < 3 && $rMonth > 10) {
            $yearOffset = 1;
        } else if ($eMonth > 10 && $rMonth < 3) {
            $yearOffset = -1;
        }

        $this->localDate = ($rYear + $yearOffset) . '-' . $eMonth . '-' . $eDay;
        $rD = new \DateTime($strDate);
        $eD = new \DateTime($this->localDate);

        $nDiff = (int) $rD->diff($eD)->format('%r%a');

        $this->days = $nDiff;
        if ($eYear == '????') {
            $this->age = null;
        } else {
            $this->age = $rYear - $eYear + $yearOffset;
        }

        if ($nDiff > 0) {
            return $nDiff <= $nDaysNext;
        } else {
            return -$nDiff <= $nDaysPrevious;
        }

        return false;
    }

    /**
     * Compare two events by by their date, then by their title.
     * Used for sorting
     *
     * @param Event $e1 Event #1
     * @param Event $e2 Event #2
     *
     * @return integer x < 0: e1 is less than e2
     *                 x > 0: e1 is larger than e2
     */
    public static function compare(Event $e1, Event $e2)
    {
        list($e1Year, $e1Month, $e1Day) = explode('-', $e1->date);
        list($e2Year, $e2Month, $e2Day) = explode('-', $e2->date);

        if ($e1Month < 3 && $e2Month > 10) {
            return 1;
        } else if ($e1Month > 10 && $e2Month < 3) {
            return -1;
        } else if ($e1Month != $e2Month) {
            return $e1Month - $e2Month;
        } else if ($e1Day != $e2Day) {
            return $e1Day - $e2Day;
        }
        return strcmp($e1->title, $e2->title);
    }
}
?>