User:Enterprisey/schedule-local-time.js

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mw.hook("wikipage.content").add(function(){
function fixScheduleTime(time){
  if(time.indexOf("-")>=0) {
    var times = time.split("-");
    return fixScheduleTime(times[0]) + " – " + fixScheduleTime(times[1]) + " (" + times[0] + " – " + times[1].trim() + ")";
  } else {
    var parts = time.split(":");
    var date = new Date();
    if(parts.length > 1) {
      date.setUTCHours((parseInt(parts[0]) + 5) % 24);
      date.setMinutes(parseInt(parts[1].trim()));
    }
    return date.toLocaleTimeString().replace( /(\d?\d:\d\d):\d\d/, "$1" );
  }
}

$("table.wikitable").each(function(_idx,table){
  Array.prototype.slice.call(table.rows).forEach(function(row,idx){
    if(idx>0)row.cells[0].textContent = fixScheduleTime(row.cells[0].textContent)
  })
});
});