ics-php-renderer/php/calendar-month.php

<?php
require_once ('ics.php');

$ical = null;
if (isset ($_GET["ics_url"])) {
    $ical = getCalendar($_GET["ics_url"]);
}

/**
 * Sets and returns the global $requested_month variable
 * to either the GET requested month, or the current month
 * 
 * @return int Month number
 */
function getRequestedMonth () {
    global $_GET, $requested_month;

    if (isset ($requested_month)) return $requested_month;

    if (
        ! isset ($_GET["month"]) ||
        ! ($requested_month = intval ($_GET["month"])) ||
        $requested_month > 12 ||
        $requested_month < 1
    ) {
        $requested_month = idate("m");
    }

    return $requested_month;
}

/**
 * Echoes the requested months' name
 */
function echoMonthName () {
    echo getLocalizedMonthName (getRequestedMonth ());
}

/**
 * Returns HTML for a days' events list (CSS class day-events-scrollbox)
 *
 * @param ICal $ical  ICal object
 * @param int  $day   Day of month
 * @param int  $month Month (defaults to current month)
 * @param int  $year  Year (defaults to current year)
 *  
 * @return string HTML containing DIV of class day-events-scrollbox
 * @return false  False on failure
 */
function generateDayEventsList ($ical, $day, $month = null, $year = null) {
    if (! $ical) return false;

    $html = '
        <div class="day-events-scrollbox">
            <div class="day-events autoscroll">
                %s
            </div>
            <div class="day-events-shadow"></div>
        </div>
    ';

    foreach (getEventsForDay ($ical, $day, $month, $year) as $event) {
        $dtstart = $ical -> iCalDateToDateTime($event -> dtstart_array[3]);
        $dtend   = $ical -> iCalDateToDateTime($event -> dtend_array[3]);
        
        $today_start = new DateTime(
            date('Y-m-d H:i:s', mktime(0, 0, 0, $month, $day, $year)),
            $dtstart -> getTimezone()
        );
        $today_end = clone $today_start; $today_end -> modify("+1 day");
        
        $time_separator = "-";
        $time_prefix    = "";
        $time_start = $dtstart -> format('H:i');
        $time_end   = $dtend   -> format('H:i');

        // When start date is in past, don't display start time
        if ($dtstart < $today_start) {
            $time_start = "";
            $time_separator = "Bis ";
        }

        // When end date is in future, don't display end time
        if ($dtend > $today_end) {
            $time_end = "";
            $time_separator = "";
            $time_prefix = "Ab ";
        }
            
        // Assemble time display string
        $time_str = "{$time_prefix}{$time_start}{$time_separator}{$time_end}";

        // Check if event is all day
        if ($time_start == "00:00" && $time_end == "00:00") {
            //$time_str = "Ganztägig";
            $time_str = "";
        }

        // Check if event is multi day
        if ($time_start == "" && $time_end == "") {
            $time_str = "Mehrtägig";
        }

        // Check if multi day event without start times
        if ($time_start . $time_end == "00:00") {
            $time_str = "Mehrtägig";
        }

        $html = sprintf (
            $html,
            sprintf(
                '<span class="day-event-entry">
                    <span class="time">%s</span>
                    <span class="description">%s</span>
                </span>
                %%s',
                $time_str,
                $event -> summary
            ),
        );
    }

    $html = sprintf ($html, "<!-- {$day} -->");
    return $html;
}

/**
 * Returns HTML with all elements going in the DIV with CSS class calendar-body
 * 
 * @param ICal $Ical  ICal object
 * @param int  $month Month
 * 
 * @return string HTML containing elements for calendar body
 * @return false  False on failure
 */
function generateCalendarBodyItems ($ical, $month) {
    if ($month > 12 || $month < 1) return false;

    $html    = '%s';
    $odd_row = false;

    // Number of days in month
    $month_max_days = idate ("t", mktime (0, 0, 0, $month));

    // First of month unix timestamp
    $first_of_month = new DateTime (
        date('Y-m-d H:i:s', mktime (0, 0, 0, $month, 1))
    );

    // Days needed to pad the calendar at the start
    $pad_days = idate ("N", $first_of_month -> getTimestamp()) - 1;

    // First of the month, minus the pad days
    $day = $first_of_month -> modify ("-{$pad_days} days");

    // Number of total entries in calendar
    $num_rows = ceil (($pad_days + $month_max_days) / 7);
    $num_entries = ($num_rows * 8);

    // Loop over all entry slots and generate entries
    for ($item_index = 0; $item_index < $num_entries; $item_index ++) {
        
        // If item_index is beginning of row, add week number entry
        if ($item_index % 8 == 0) {
            $week = $day -> format ("W");
            $html = sprintf (
                $html,
                "<div class=\"calendar-header-value\">Woche {$week}</div>
                %s",
            );

            // Swap odd and even rows
            $odd_row = ! $odd_row;

            continue;
        }

        $calendar_entry_html = '
            <div class="calendar-entry %s %s %s">
                <div class="day-header %s"><span>%d.</span></div>
                %s
            </div>
            %s
        ';

        $html = sprintf (
            $html,
            sprintf( 
                $calendar_entry_html,
                $odd_row? "odd-row" : "even-row",
                (isDateTimeWithinMonth ($day, $month)) ? "" : "other-month",
                (isDateTimeDuringWeekend ($day)) ? "weekend" : "",
                (isDateTimeToday ($day))? "today" : "",
                $day -> format ("d"),
                generateDayEventsList(
                    $ical,
                    intval ($day -> format ("d")),
                    intval ($day -> format ("m")),
                ),
                "%s"
            )
        );

        $day -> modify ("+1 day");
    }

    return sprintf($html, "");
}

/**
 * Echoes HTML to insert all calendar day entries
 */
function echoCalendarEntries() {
    global $ical;

    echo generateCalendarBodyItems($ical, getRequestedMonth());
}