manager is now using react

1 files changed, 242 insertions, 0 deletions

diff --git a/174bg/manager/src/lib/oncallTime.js b/174bg/manager/src/lib/oncallTime.js
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+++ b/174bg/manager/src/lib/oncallTime.js
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+export const DAYS_OF_WEEK = [
+    "Monday",
+    "Tuesday",
+    "Wednesday",
+    "Thursday",
+    "Friday",
+    "Saturday",
+    "Sunday",
+];
+
+// Sunday-first, matching Date#getDay()/getUTCDay() and Intl's "weekday"
+export const WEEKDAY_NAMES = [
+    "Sunday",
+    "Monday",
+    "Tuesday",
+    "Wednesday",
+    "Thursday",
+    "Friday",
+    "Saturday",
+];
+export const WEEKDAY_INDEX = Object.fromEntries(
+    WEEKDAY_NAMES.map((d, i) => [d, i]),
+);
+
+export function pad2(n) {
+    return String(n).padStart(2, "0");
+}
+
+export function getBrowserTimeZone() {
+    try {
+        return Intl.DateTimeFormat().resolvedOptions().timeZone || "UTC";
+    } catch {
+        return "UTC";
+    }
+}
+
+export function listTimeZones() {
+    if (typeof Intl.supportedValuesOf === "function") {
+        try {
+            return Intl.supportedValuesOf("timeZone");
+        } catch {
+            // fall through to the fallback list below
+        }
+    }
+    return [
+        "UTC",
+        "America/Los_Angeles",
+        "America/Denver",
+        "America/Chicago",
+        "America/New_York",
+        "America/Sao_Paulo",
+        "Europe/London",
+        "Europe/Paris",
+        "Europe/Berlin",
+        "Europe/Moscow",
+        "Africa/Johannesburg",
+        "Asia/Dubai",
+        "Asia/Kolkata",
+        "Asia/Shanghai",
+        "Asia/Tokyo",
+        "Australia/Sydney",
+        "Pacific/Auckland",
+    ];
+}
+
+// Offset (ms) of `timeZone` from UTC at the instant `date` represents.
+export function tzOffsetMs(date, timeZone) {
+    const dtf = new Intl.DateTimeFormat("en-US", {
+        timeZone,
+        hourCycle: "h23",
+        year: "numeric",
+        month: "2-digit",
+        day: "2-digit",
+        hour: "2-digit",
+        minute: "2-digit",
+        second: "2-digit",
+    });
+    const parts = {};
+    for (const { type, value } of dtf.formatToParts(date)) {
+        parts[type] = value;
+    }
+    const asUTC = Date.UTC(
+        Number(parts.year),
+        Number(parts.month) - 1,
+        Number(parts.day),
+        parts.hour === "24" ? 0 : Number(parts.hour),
+        Number(parts.minute),
+        Number(parts.second),
+    );
+    return asUTC - date.getTime();
+}
+
+// Formats `timeZone`'s UTC offset at `date` as "UTC+HH:MM"/"UTC-HH:MM".
+export function formatUtcOffset(timeZone, date = new Date()) {
+    const totalMinutes = Math.round(tzOffsetMs(date, timeZone) / 60000);
+    const sign = totalMinutes < 0 ? "-" : "+";
+    const abs = Math.abs(totalMinutes);
+    return `UTC${sign}${pad2(Math.floor(abs / 60))}:${pad2(abs % 60)}`;
+}
+
+// Nearest same-or-later calendar date whose local weekday in `timeZone`
+// is `day` - used as a DST-correct anchor for the conversion below.
+function nextLocalDateFor(day, timeZone) {
+    const dtf = new Intl.DateTimeFormat("en-US", {
+        timeZone,
+        year: "numeric",
+        month: "2-digit",
+        day: "2-digit",
+        weekday: "long",
+    });
+    const parts = {};
+    for (const { type, value } of dtf.formatToParts(new Date())) {
+        parts[type] = value;
+    }
+    const diff = (WEEKDAY_INDEX[day] - WEEKDAY_INDEX[parts.weekday] + 7) % 7;
+    const base = new Date(
+        Date.UTC(Number(parts.year), Number(parts.month) - 1, Number(parts.day)),
+    );
+    base.setUTCDate(base.getUTCDate() + diff);
+    return base;
+}
+
+// Nearest same-or-later UTC calendar date whose UTC weekday is `day`.
+function nextUtcDateFor(day) {
+    const now = new Date();
+    const diff = (WEEKDAY_INDEX[day] - now.getUTCDay() + 7) % 7;
+    const base = new Date(
+        Date.UTC(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate()),
+    );
+    base.setUTCDate(base.getUTCDate() + diff);
+    return base;
+}
+
+// Converts a weekday + "HH:MM" wall-clock time in `timeZone` to the
+// equivalent UTC weekday + "HH:MM" (the day may shift due to the offset).
+export function localDayTimeToUtc(day, time, timeZone) {
+    const [hour, minute] = time.split(":").map(Number);
+    const base = nextLocalDateFor(day, timeZone);
+    const guess = Date.UTC(
+        base.getUTCFullYear(),
+        base.getUTCMonth(),
+        base.getUTCDate(),
+        hour,
+        minute,
+    );
+    const offset = tzOffsetMs(new Date(guess), timeZone);
+    const actual = new Date(guess - offset);
+    return {
+        day: WEEKDAY_NAMES[actual.getUTCDay()],
+        time: `${pad2(actual.getUTCHours())}:${pad2(actual.getUTCMinutes())}`,
+    };
+}
+
+// Converts a UTC weekday + "HH:MM" back to weekday + "HH:MM" wall-clock
+// time in `timeZone`.
+export function utcDayTimeToLocal(day, time, timeZone) {
+    const [hour, minute] = time.split(":").map(Number);
+    const base = nextUtcDateFor(day);
+    const instant = new Date(
+        Date.UTC(
+            base.getUTCFullYear(),
+            base.getUTCMonth(),
+            base.getUTCDate(),
+            hour,
+            minute,
+        ),
+    );
+    const dtf = new Intl.DateTimeFormat("en-US", {
+        timeZone,
+        hourCycle: "h23",
+        weekday: "long",
+        hour: "2-digit",
+        minute: "2-digit",
+    });
+    const parts = {};
+    for (const { type, value } of dtf.formatToParts(instant)) {
+        parts[type] = value;
+    }
+    return {
+        day: parts.weekday,
+        time: `${parts.hour === "24" ? "00" : parts.hour}:${parts.minute}`,
+    };
+}
+
+export function getEffectiveTimezone(raw) {
+    return raw.timezone || getBrowserTimeZone();
+}
+
+// Converts the stored UTC schedule to local wall-clock times, keyed by
+// local weekday, for display/editing.
+export function utcScheduleToLocal(raw, timeZone) {
+    const local = {};
+    for (const day of DAYS_OF_WEEK) {
+        const entry = raw[day];
+        if (!entry?.available) continue;
+        const start = utcDayTimeToLocal(day, entry.start, timeZone);
+        const end = utcDayTimeToLocal(day, entry.end, timeZone);
+        local[start.day] = {
+            available: true,
+            start: start.time,
+            end: end.time,
+        };
+    }
+    return local;
+}
+
+// Converts a local-keyed schedule (from the edit form) to UTC for storage.
+export function localScheduleToUtc(local, timeZone) {
+    const utc = {};
+    for (const day of DAYS_OF_WEEK) {
+        const entry = local[day];
+        if (!entry?.available) continue;
+        const start = localDayTimeToUtc(day, entry.start || "00:00", timeZone);
+        const end = localDayTimeToUtc(day, entry.end || "00:00", timeZone);
+        utc[start.day] = { available: true, start: start.time, end: end.time };
+    }
+    return utc;
+}
+
+// onCallSchedule is stored as JSON, UTC-normalized:
+// { timezone: "IANA/Zone", [utcDay]: { available, start, end } }
+export function getOnCallRaw(record) {
+    const raw = record?.onCallSchedule;
+    if (!raw) return {};
+    if (typeof raw === "string") {
+        try {
+            return JSON.parse(raw) || {};
+        } catch {
+            return {};
+        }
+    }
+    return { ...raw };
+}
+
+// Legacy records saved before timezone support has no `timezone` key - those
+// values are already local wall-clock times, so skip conversion.
+export function getLocalOnCallSchedule(record) {
+    const raw = getOnCallRaw(record);
+    const timeZone = getEffectiveTimezone(raw);
+    const schedule = raw.timezone ? utcScheduleToLocal(raw, timeZone) : raw;
+    return { timeZone, schedule };
+}