arch-panel-extension-browser/src/domain/ramp-forecast.js

(() => {
  function create(dependencies) {
    const {
      toNumber,
      normalizeString,
      parseDatePreservingDateOnly,
      formatWeekNumber,
    } = dependencies;

    function buildRampForecastComparisonRows(workloads) {
      return (workloads || [])
        .flatMap((workload) => {
          const startDate = parseDatePreservingDateOnly(
            workload.consumptionStartDate
          );

          if (Number.isNaN(startDate.getTime())) {
            return [];
          }

          const startMonth = startDate.getMonth() + 1;
          const startYear = startDate.getFullYear();
          const workloadLabel = `${workload.name || "Unnamed workload"}${
            workload.description ? ` | ${workload.description}` : ""
          }`;

          return (workload.forecast || [])
            .map((forecastItem) => {
              const forecastMonth = parseForecastMonthNumber(forecastItem.month);
              const forecastYear = toNumber(forecastItem.year);

              if (!forecastMonth || !forecastYear) {
                return null;
              }

              const monthIndex =
                (forecastYear - startYear) * 12 +
                (forecastMonth - startMonth) +
                1;

              const currentValue = toNumber(
                forecastItem.adjustedConsumptionAmount
              );
              const calculatedValue =
                monthIndex >= 1 && monthIndex <= 12
                  ? calculateRampForecastAmount({
                      adjustedACR: workload.adjustedACR,
                      rampMonths: workload.rampMonths,
                      monthIndex,
                      consumptionStartDate: startDate,
                    })
                  : 0;

              return {
                workloadLabel,
                periodLabel: formatForecastPeriodLabel(forecastYear, forecastMonth),
                currentValue,
                calculatedValue,
                delta: currentValue - calculatedValue,
                monthIndex,
                year: forecastYear,
                month: forecastMonth,
                sortKey: `${workloadLabel}|${String(forecastYear).padStart(
                  4,
                  "0"
                )}-${String(forecastMonth).padStart(2, "0")}`,
              };
            })
            .filter(Boolean);
        })
        .sort((left, right) => left.sortKey.localeCompare(right.sortKey));
    }

    function hasRampForecastMismatch(workload) {
      return buildRampForecastComparisonRows([workload]).some((row) =>
        isNonZeroAmount(row.delta)
      );
    }

    function calculateRampForecastAmount({
      adjustedACR,
      rampMonths,
      monthIndex,
      consumptionStartDate,
    }) {
      const annualValue = toNumber(adjustedACR);
      const ramp = Math.max(0, toNumber(rampMonths));
      const month = Math.max(1, toNumber(monthIndex));

      if (!annualValue) {
        return 0;
      }

      if (ramp <= 0) {
        return Math.round(
          (annualValue / 12) *
            getStartMonthProrationFactor(month, consumptionStartDate)
        );
      }

      const steadyStateMonthlyAmount = (2 * annualValue) / (24 - ramp);
      const rampStepCount = ramp + 1;
      const calculatedAmount =
        month <= rampStepCount
          ? steadyStateMonthlyAmount * (month / rampStepCount)
          : steadyStateMonthlyAmount;

      return Math.round(
        calculatedAmount * getStartMonthProrationFactor(month, consumptionStartDate)
      );
    }

    function getStartMonthProrationFactor(monthIndex, consumptionStartDate) {
      if (toNumber(monthIndex) !== 1) {
        return 1;
      }

      const startDate = parseDatePreservingDateOnly(consumptionStartDate);

      if (Number.isNaN(startDate.getTime())) {
        return 1;
      }

      const daysInMonth = new Date(
        startDate.getFullYear(),
        startDate.getMonth() + 1,
        0
      ).getDate();
      const remainingDays = daysInMonth - startDate.getDate() + 1;

      return Math.max(0, Math.min(1, remainingDays / daysInMonth));
    }

    function isNonZeroAmount(value) {
      return Math.abs(toNumber(value)) > 0.000001;
    }

    function parseForecastMonthNumber(value) {
      if (typeof value === "number") {
        return value >= 1 && value <= 12 ? value : 0;
      }

      const normalized = normalizeString(value);
      const numericMonth = Number.parseInt(normalized, 10);

      if (numericMonth >= 1 && numericMonth <= 12) {
        return numericMonth;
      }

      const monthMap = {
        JAN: 1,
        JANUARY: 1,
        FEB: 2,
        FEBRUARY: 2,
        MAR: 3,
        MARCH: 3,
        APR: 4,
        APRIL: 4,
        MAY: 5,
        JUN: 6,
        JUNE: 6,
        JUL: 7,
        JULY: 7,
        AUG: 8,
        AUGUST: 8,
        SEP: 9,
        SEPT: 9,
        SEPTEMBER: 9,
        OCT: 10,
        OCTOBER: 10,
        NOV: 11,
        NOVEMBER: 11,
        DEC: 12,
        DECEMBER: 12,
      };

      return monthMap[normalized] || 0;
    }

    function formatForecastPeriodLabel(year, month) {
      const fiscalYear = month >= 6 ? year + 1 : year;
      const fiscalYearLabel = formatWeekNumber(fiscalYear % 100);
      const monthLabel = new Intl.DateTimeFormat("en-US", {
        month: "short",
      }).format(new Date(year, month - 1, 1));

      return `FY${fiscalYearLabel} ${monthLabel}`;
    }

    function createForecastUpdatePayload(rows, userEmail = "") {
      return (rows || [])
        .filter((row) => row.year && row.month)
        .map((row) => ({
          year: toNumber(row.year),
          month: toNumber(row.month),
          amount: toNumber(row.calculatedValue),
          updatedBy: userEmail,
        }));
    }

    return {
      buildRampForecastComparisonRows,
      hasRampForecastMismatch,
      calculateRampForecastAmount,
      getStartMonthProrationFactor,
      isNonZeroAmount,
      parseForecastMonthNumber,
      formatForecastPeriodLabel,
      createForecastUpdatePayload,
    };
  }

  globalThis.ArchPanelRampForecastDomain = Object.freeze({
    create,
  });
})();