#!/bin/sh
# generates the upcoming meetups for Funkfeuer Graz Homepage
#
# this script should be called by cron every day (night)
# how far in the future should i go?
LIMIT=3

# uncomment to enable debug
#DEBUG=1

# where to put the output files?
NEXT_FILE="next.html"
AFTER_FILE="after.html"
NEXTTYPE_FILE="nexttype.html"
NEXT_BEGINTIME_FILE="nextbegin.html"

DOW=`date +"%u"`
if [ $DOW -eq 1 ]; then
  DOM=`date +"%e"`
  TS=`date +"%s"`
else
  DOM=`date --date="next monday" +"%e"`
  TS=`date --date="next monday" +"%s"`
fi

if [ $TS -lt $(date --date="2023-08-22" +"%s") ]; then
  # skip specific date
  # (only works if it's already that day - for future cases specify exact upcoming date below!)
  DOM=`date --date="next monday" +"%e"`
  TS=`date --date="next monday" +"%s"`
fi

MEETUPS=""
MEETUPTYPES=""
CNT=0
while true; do
  if [ -n "$DEBUG" ]; then echo -n "check day($TS): "`date --date="@$TS" +"%d.%m.%Y"`; fi

  #skip specific date in future
  ymd_to_skip="2024-04-01"
  ymd=$(date --date=@$TS +"%Y-%m-%d")
  if [ $ymd = $ymd_to_skip ]; then
     TS=$((TS + (7 * 24 * 3600)))
     DOM=`date --date="@$TS" +"%e"`
     continue
  fi

  if [ $DOM -le 7 ] || ([ $DOM -ge 15 ] && [ $DOM -le 21 ]); then
    if [ $DOM -le 7 ]; then
      MTYP="Tech/Core Treffen"
      BEGINTIME="20:30"
    else
      MTYP="allgemeines Funkfeuertreffen"
      BEGINTIME="20:30"
    fi
    if [ -n "$DEBUG" ]; then echo " -> ok $MTYP"; fi
    MEETUPS="$MEETUPS $TS"
    MEETUPTYPES="$MEETUPTYPES $MTYP"
    CNT=$((CNT + 1))
    if [ $CNT -ge $LIMIT ]; then
      break;
    fi
  else
    if [ -n "$DEBUG" ]; then echo ""; fi
  fi
  TS=$((TS + (7 * 24 * 3600)))
  DOM=`date --date="@$TS" +"%e"`
done

set -- $MEETUPS
NEXT=$1
shift
FUTURE=$@

set -- $MEETUPTYPES
NEXTMTYP=$1
shift
FUTUREMTYP=$@

date --date="@$NEXT" +"%d.%m.%Y" > "$NEXT_FILE.new"
echo $NEXTMTYP > "$NEXTTYPE_FILE.new"
echo $BEGINTIME > "$NEXT_BEGINTIME_FILE.new"
CNT=0
echo "<ul>" > "$AFTER_FILE.new"
for meetup in $FUTURE; do
  set -- $FUTUREMTYP
  mtext=$1
  shift
  FUTUREMTYP=$@

  echo "  <li>"`date --date="@$meetup" +"%d.%m.%Y"`" : $mtext</li>" >> "$AFTER_FILE.new"
  CNT=$((CNT + 1))
done
echo "</ul>" >> "$AFTER_FILE.new"
mv "$NEXT_FILE.new" "$NEXT_FILE"
mv "$NEXT_BEGINTIME_FILE.new" "$NEXT_BEGINTIME_FILE"
mv "$NEXTTYPE_FILE.new" "$NEXTTYPE_FILE"
mv "$AFTER_FILE.new" "$AFTER_FILE"

exit 0