Use Javascript to compare time ranges in PDF form

Question

I have a PDF form with 6 different time periods for each day of the month and I need to make sure those time periods do not overlap when the user completes them. Not all time periods may be completed, but the ones that do must be unique. I have taken inspiration from this previous post Use JavaScript to compare time ranges specifically the contribution by @RobG. However, my lack of scripting knowledge is hampering my ability to mold that code for my specific application. In addition to have the time periods verified, I also have to repeat this for every day on the form but I would like to do it one day at a time particularly when the entries are made for that day. Since this is a PDF form, I am not certain how to execute that validation. For example, should it execute every time a time period is completed? That is, have a Start Time and and End Time? So it would act as a "validation" script for that time entry? Here is a sample of what the form looks like:

Here is my attempt at updating the code for my form:

var TimeIn1 = this.getField("Day1Pd1TimeInRes").value;
var TimeOut1 = this.getField("Day1Pd1TimeOutRes").value;
var TimeIn2 = this.getField("Day1Pd2TimeInRes").value;
var TimeOut2 =  this.getField("Day1Pd2TimeOutRes").value;
var TimeIn3 = this.getField("Day1Pd3TimeInRes").value;
var TimeOut3 = this.getField("Day1Pd3TimeOutRes").value;
var TimeIn4 = this.getField("Day1Pd4TimeInRes").value;
var TimeOut4 = this.getField("Day1Pd4TimeOutRes").value;
var TimeIn5 = this.getField("Day1Pd5TimeInRes").value;
var TimeOut5 =  this.getField("Day1Pd5TimeOutRes").value;
var TimeIn6 = this.getField("Day1Pd6TimeInRes").value;
var TimeOut6 = this.getField("Day1Pd6TimeOutRes").value;

var timeSlots = [
  {BeginTime: new Date("10/25/2015 " + TimeIn1),
   EndTime: new Date("10/25/2015 " + TimeOut1)},
  {BeginTime: new Date("10/25/2015 " + TimeIn2),
   EndTime: new Date("10/25/2015 " + TimeOut2)},
  {BeginTime: new Date("10/25/2015 " + TimeIn3),
   EndTime: new Date("10/25/2015 " + TimeOut3)},
  {BeginTime: new Date("10/25/2015 " + TimeIn4),
   EndTime: new Date("10/25/2015 " + TimeOut4)},
  {BeginTime: new Date("10/25/2015 " + TimeIn5),
   EndTime: new Date("10/25/2015 " + TimeOut5)},
  {BeginTime: new Date("10/25/2015 " + TimeIn6),
   EndTime: new Date("10/25/2015 " + TimeOut6)}
];
function slotFits(slot) {
  if (timeSlots.length == 0) return true; // If no slots, must fit
  return timeSlots.some(function(s, i) {
    return (i == 0 && slot.EndTime <= s.BeginTime) || //slot is before all others
  (s.EndTime <= slot.BeginTime && !timeSlots[i + 1]) || //slot is after all others
  (s.EndTime <= slot.BeginTime && timeSlots[i + 1].BeginTime >= slot.EndTime) // Slot between others
  });
}

[{BeginTime: new Date("10/25/2015 " + TimeIn1),
  EndTime: new Date("10/25/2015 " + TimeOut1)},
 {BeginTime: new Date("10/25/2015 " + TimeIn2),
  EndTime: new Date("10/25/2015 " + TimeOut2)},
 {BeginTime: new Date("10/25/2015 " + TimeIn3),
  EndTime: new Date("10/25/2015 " + TimeOut3)},
 {BeginTime: new Date("10/25/2015 " + TimeIn4),
  EndTime: new Date("10/25/2015 " + TimeOut4)},
 {BeginTime: new Date("10/25/2015 " + TimeIn5),
  EndTime: new Date("10/25/2015 " + TimeOut5)},
 {BeginTime: new Date("10/25/2015 " + TimeIn6),
  EndTime: new Date("10/25/2015 " + TimeOut6)},
].forEach(function(slot, i) {
  app.alert('Slot ' + i + ': ' + slotFits(slot));
});

In this sample I spelled out the field names, but because I will be repeating this for up to 31 days at a time, I would like to find a way to create a document script where I can put in the 'TimeIn' and 'TimeOut variables and call them for each day, but I think I can get away without that if necessary, just concerned about form size repeating that much code for 6 periods for potentially 31 days. Thank you!

Edit: Time values are HH:mm

Answer 1

Let's rewrite this a little, because the typically solution to "things are getting weirdly complicated" is typically "pick a better data structure", which in this case means using an Entry representation, and making that do the work for you.

Given that Foxit apparently does not support modern JS, using older ES5 this would look a little something like:

function Entry(pdfObject, day, pd, dateOffset) {
  this.id = day + '-' + pd;
  this.in = pdfObject.getField('Day'+day+'Pd'+pd+'TimeInRes').value;
  this.out = pdfObject.getField('Day'+day+'Pd'+pd+'TimeOutRes').value;
  this.begin = new Date(dateOffset+' '+this.in);
  this.end = new Date(dateOffset+' '+this.out);
  this.interval = this.end.getTime() - this.begin.getTime(); 
}

Entry.prototype = {
  checkFit: function checkFit(entries) {
    // 1: find out where our start fits into the list of start times
    var start = -1, l = entries.length, other, i, e;
    for (i=0; i<l; i++) {
      e = entries[i];
      if (this.begin < e.begin) {
        start = i;
        other = e;
      }
      if (this.begin > e.begin) break;
    }
    // are we the last entry? if so, we fit if we start after the last end.
    if (!other || start === l-1) return (this.begin > entries[l-1].end);
    // IF not, there is a next entry; do we end before that begins?
    return other.begin <= this.end;
  }
}

Entry.loadAll = function loadAll(pdfObject, day, dateOffset) {
  return [1,2,3,4,5,6]
         .map(function(i) { return new Entry(pdfObject, day, i, dateOffset); })
         .sort(function(a,b) { return a.end - b.end; });
}

And we can then make use of this object using code like:

// Make sure we have a reference to the pdf API so we can getField etc.
var pdfObject = this;

// I'm assuming the day and date offset should not be hardcoded
var entries = Entry.loadAll(pdfObject, 1, "10/25/2015");

// check the entries
entries.forEach( function(entry) {
  let fits = entry.checkFit(entries);
  console.log('Slot check for entry '+entry.id+': '+fits);
});