Creating Object with FY year and Quarter values

I'm trying to create an object whose 'key' is the fiscal year and 'values' are the quarter dates. You can check the sample format below.

//Format
{
2021:{
   "12 / 30 / 2021",
   "09 / 30 / 2021",
   "06 / 30 / 2021",
},
}

Based on the Fiscal year - end date I'm able to group the quarters but calculating the fiscal year is what I need help with. The most repeated years will be the fiscal year and if an FY has quarters with two different years with an exact count i.e.2, then we can pick the smallest value. You can observe edge cases in the quarter dates I've provided. Please find the code and expected output below.

const quarters = [
  "12 / 30 / 2021",
  "09 / 30 / 2021",
  "06 / 30 / 2021",
  "03 / 30 / 2021",
  "12 / 30 / 2020",
  "09 / 30 / 2020",
  "06 / 30 / 2020",
  "12 / 30 / 2019",
  "09 / 30 / 2019",
  "06 / 30 / 2019",
  "03 / 30 / 2019",
  "12 / 30 / 2018",
  "09 / 30 / 2018",
  "06 / 30 / 2018",
  "03 / 30 / 2018",
];
const periods = [
  "03 / 30 / 2021",
  "12 / 30 / 2019",
  "12 / 30 / 2018",
  "12/30/2017"
];

const groupQuarters = [];
let group = [];
while (periods.length > 0) {
  let p = new Date(periods[0].toString());
  group = [];
  while (quarters.length > 0) {
      let q = new Date(quarters[0].toString());
      if (q > p) {
          group.push(quarters[0]);
          quarters.shift();
      } else {
          break;
      }
  }
  const yearCal = (groups) => {
      // unable to figure this out.
      return 2020;
  }
  groupQuarters.push({ [yearCal(group)]: group });
  periods.shift();
}


console.log(groupQuarters);

Expected output:
[
  {
      2021: [
          '12 / 30 / 2021',
          '09 / 30 / 2021',
          '06 / 30 / 2021'
      ]
  },
  {
      2020: [
          '03 / 30 / 2021',
          '12 / 30 / 2020',
          '09 / 30 / 2020',
          '06 / 30 / 2020'
      ]
  },
  {
      2019: [
          '12 / 30 / 2019',
          '09 / 30 / 2019',
          '06 / 30 / 2019',
          '03 / 30 / 2019'
      ]
  },
  {
      2018: [
          '12 / 30 / 2018',
          '09 / 30 / 2018',
          '06 / 30 / 2018',
          '03 / 30 / 2018'
      ]
  }
]

Test Case - 2:
const quarters = [
  "12 / 30 / 2020",
  "09 / 30 / 2020",
  "06 / 30 / 2020",
  "03 / 30 / 2020",
  "12 / 30 / 2019",
  "09 / 30 / 2019",
  "06 / 30 / 2019",
  "03 / 30 / 2019",
  "12 / 30 / 2018"
];
const periods = [
  "09 / 30 / 2020",
  "09 / 30 / 2019",
  "09 / 30 / 2018",
];

Expected Output:
[
  {
    2021: [
      '12 / 30 / 2020',
    ]
  },
  {
    2020: [
      "09 / 30 / 2020",
      "06 / 30 / 2020",
      "03 / 30 / 2020",
      "12 / 30 / 2019",
    ]
  },
  {
    2019: [
      "09 / 30 / 2019",
      "06 / 30 / 2019",
      "03 / 30 / 2019",
      "12 / 30 / 2018",
    ]
  },
]

CodePudding user response：

You can try it :

const quarters = [
    "12 / 30 / 2021",
    "09 / 30 / 2021",
    "06 / 30 / 2021",
    "03 / 30 / 2021",
    "12 / 30 / 2020",
    "09 / 30 / 2020",
    "06 / 30 / 2020",
    "12 / 30 / 2019",
    "09 / 30 / 2019",
    "06 / 30 / 2019",
    "03 / 30 / 2019",
    "12 / 30 / 2018",
    "09 / 30 / 2018",
    "06 / 30 / 2018",
    "03 / 30 / 2018",
]
const periods = [
    "03 / 30 / 2021",
    "12 / 30 / 2019",
    "12 / 30 / 2018",
    "12/30/2017"
]
const quarters1 = [
  "12 / 30 / 2020",
  "09 / 30 / 2020",
  "06 / 30 / 2020",
  "03 / 30 / 2020",
  "12 / 30 / 2019",
  "09 / 30 / 2019",
  "06 / 30 / 2019",
  "03 / 30 / 2019",
  "12 / 30 / 2018"
];
const periods1 = [
  "09 / 30 / 2020",
  "09 / 30 / 2019",
  "09 / 30 / 2018",
];
const getGroupQuarter = (qt, pr) => {
  let tmpCheck = qt
  return pr.reduce((result,period) => {
    let datePeriod = new Date(period)
    let key = getKeyQuarter(datePeriod)
    let qtrFill =  tmpCheck.filter(quarter => new Date(quarter) > datePeriod)
    tmpCheck =  tmpCheck.filter(quarter =>!(new Date(quarter) > datePeriod))
    return !qtrFill.length ? result :[...result, {[key] : qtrFill}]
  }, [])
}
const getKeyQuarter = (pr) => {
  let monthValidate = pr.getMonth()
  return monthValidate > 5 ? pr.getFullYear()   1 : pr.getFullYear()
}
console.log(getGroupQuarter(quarters1, periods1));
console.log(getGroupQuarter(quarters, periods));

CodePudding user response：

Assuming there are no gaps within a period -- i.e. no gaps between two quarters that belong to the same period -- you could apply this logic:

When the last quarter is known of the period (i.e. it equals the period-end), subtract 2 quarters and take that quarter's year as financial year
When the last quarter is not known of the period -- this may happen at the start of the array, where the current period is not yet completed -- add one quarter to the first quarter of that period and take that quarter's year as financial year.

As it is nice to map the periods array one-to-one to get the result array, it might sometimes be needed to strip the last period entry (like in the test case 1), or insert an unfinished period at the start of that array (also in test case 1).

Not related, but I avoided Date objects for this task, and included functions to convert the input strings to numbers and back:

function chunkByYear(quarters, periods) {
    // Converter functions between string and unique quarter number
    const toQuarter = s => s.match(/^\d |\d $/g).reduce((m, y) => m/3 - 1   y*4);
    const toDate = q => ((q % 4   1)*3   "/30/"   (q >> 2)).padStart(10, "0");

    const periodNums = periods.map(toQuarter);
    const quarterNums = quarters.map(toQuarter);
    // Make sure all quarters are after at least one period end
    while (quarterNums[quarterNums.length-1] <= periodNums[periodNums.length-1]) periodNums.push(periodNums[periodNums.length-1] - 4);
    // Remove periods that have no content:
    while (quarterNums[0] <= periodNums[0]) periodNums.shift();
    quarterNums.push(0); // To make sure `findIndex` always finds an index
    return periodNums.map((p, i, {length}) => {
        const period = quarterNums.splice(0, quarterNums.findIndex(q => q <= p));
        return { [(i ? period[0] - 2 : period[period.length-1]   1) >> 2]: period.map(toDate) };
    });
}

{ // test 1
    const quarters = [
        "12 / 30 / 2021", "09 / 30 / 2021", "06 / 30 / 2021",
        "03 / 30 / 2021", "12 / 30 / 2020", "09 / 30 / 2020", "06 / 30 / 2020",
        "12 / 30 / 2019", "09 / 30 / 2019", "06 / 30 / 2019", "03 / 30 / 2019",
        "12 / 30 / 2018", "09 / 30 / 2018", "06 / 30 / 2018", "03 / 30 / 2018",
    ];
    const periods =  ["03 / 30 / 2021", "12 / 30 / 2019", "12 / 30 / 2018", "12 / 30 / 2017"];
    console.log(chunkByYear(quarters, periods));
}
{ // test 2
    const quarters = [
        "12 / 30 / 2020",
        "09 / 30 / 2020", "06 / 30 / 2020", "03 / 30 / 2020", "12 / 30 / 2019",
        "09 / 30 / 2019", "06 / 30 / 2019", "03 / 30 / 2019", "12 / 30 / 2018"
    ];
    const periods =  ["09 / 30 / 2020", "09 / 30 / 2019", "09 / 30 / 2018"];
    console.log(chunkByYear(quarters, periods));
}
{ // test 3
    const quarters = [
        "06 / 30 / 2021", "03 / 30 / 2021", "12 / 30 / 2020", "09 / 30 / 2020",
        "06 / 30 / 2020", "03 / 30 / 2020", "12 / 30 / 2019", "09 / 30 / 2019",
        "06 / 30 / 2019",
    ];
    const periods = ["06 / 30 / 2021", "06 / 30 / 2020", "06 / 30 / 2019"];
    console.log(chunkByYear(quarters, periods));
}
{ // test 4
    const quarters = [
        "06 / 30 / 2021", "03 / 30 / 2021", "12 / 30 / 2020", "09 / 30 / 2020",
        "06 / 31 / 2020", "03 / 30 / 2020", "12 / 30 / 2019", "09 / 30 / 2019",
        "06 / 30 / 2019", "03 / 30 / 2019", "12 / 30 / 2018", "09 / 30 / 2018",
    ];
    const periods = ["06 / 30 / 2021", "06 / 31 / 2020", "06 / 30 / 2019"];
    console.log(chunkByYear(quarters, periods));
}