Function buildWeeklyEvolution

app/utils/chart-data-buckets.ts:28–74

(
  daily: DailyRawPoint[],
  rangeStartIso: string,
  rangeEndIso: string,
)

}

export function buildWeeklyEvolution(
  daily: DailyRawPoint[],
  rangeStartIso: string,
  rangeEndIso: string,
): WeeklyDataPoint[] {
  const sorted = sortedDaily(daily)
  if (sorted.length === 0) return []

  const rangeStartDate = parseIsoDate(rangeStartIso)
  const rangeEndDate = parseIsoDate(rangeEndIso)

  const buckets = new Map<number, number>()

  for (const item of sorted) {
    const itemDate = parseIsoDate(item.day)
    const offset = Math.floor((rangeEndDate.getTime() - itemDate.getTime()) / DAY_MS)
    if (offset < 0) continue
    const idx = Math.floor(offset / 7)
    buckets.set(idx, (buckets.get(idx) ?? 0) + item.value)
  }

  return Array.from(buckets.entries())
    .sort(([a], [b]) => b - a)
    .map(([idx, value]) => {
      const weekEndDate = addDays(rangeEndDate, -(idx * 7))
      let weekStartDate = addDays(weekEndDate, -6)

      // First bucket may be partial
      if (weekStartDate.getTime() < rangeStartDate.getTime()) {
        weekStartDate = rangeStartDate
        const actualDays =
          Math.floor((weekEndDate.getTime() - rangeStartDate.getTime()) / DAY_MS) + 1
        value = fillPartialBucket(value, actualDays, 7)
      }

      const weekStartIso = toIsoDate(weekStartDate)
      const weekEndIso = toIsoDate(weekEndDate)
      return {
        value,
        weekKey: `${weekStartIso}_${weekEndIso}`,
        weekStart: weekStartIso,
        weekEnd: weekEndIso,
        timestampStart: weekStartDate.getTime(),
        timestampEnd: weekEndDate.getTime(),
      }
    })
}

export function buildMonthlyEvolution(
  daily: DailyRawPoint[],