<?php

/**
 * Return examples:
 *  1) 1:15 am
 *  2) 1:15 - 2:15 pm
 *  3) 1 - 2:15 pm
 *  4) 1:15 - 2 pm
 *  5) 1 - 2 pm
 *  6) 11:15 am - 2:15 pm
 *  7) 11 am - 2 pm
 *
 * @param $params
 * @param $smarty
 * @return string *
 */
function smarty_function_time_range($params, &$smarty)
{
    $emptyText = empty($params['emptyText']) ? '' : $params['emptyText'];
    if (empty($params['start'])) {
        return $emptyText;
    }

    $options = [
        'partsFormat' => [
            'h' => '%l',
            'm' => '%M',
            'p' => '%P',
        ],
        'hourSeparator'    => ':',
        'rangeSeparator'   => ' - ',
        'showZeroMinutes'  => false,
        'showLastAmPmOnly' => true,
    ];

    $options = array_replace_recursive($options, $params);

    $getTimeFormat = function ($time, $hasAmPm = true) use ($options) {
        $part = &$options['partsFormat'];
        $format = $part['h'];
        if ($options['showZeroMinutes'] || 0 != $time['minutes']) {
            $format .= $options['hourSeparator'] . $part['m'];
        }
        if ($hasAmPm) {
            $format .= ' ' . $part['p'];
        }
        return $format;
    };

    $formatTimeRange = function ($startTime, $endTime) use ($options, &$getTimeFormat) {
        $start = getdate($startTime);
        if (empty($endTime)) {
            return strftime($getTimeFormat($start), $startTime);
        }
        $end = getdate($endTime);
        $parts = [];
        $hasStartAmPm = !$options['showLastAmPmOnly'] || ($start['hours'] < 12 && $end['hours'] >= 12);
        $parts[] = strftime($getTimeFormat($start, $hasStartAmPm), $startTime);
        $parts[] = strftime($getTimeFormat($end), $endTime);
        return implode($options['rangeSeparator'], $parts);
    };

    $startTime = strtotime($params['start']);
    $endTime = empty($params['end']) ? null : strtotime($params['end']);
    return $formatTimeRange($startTime, $endTime);
}