feat(schedule): 改為工作日排程並產出 CPM 與 PERT

以政府辦公日曆排除年度假日，並由同一份計畫計算工作日日期、浮時、關鍵路徑與 PERT 統計。

scripts/schedule.js

@@ -1,50 +1,46 @@
 #!/usr/bin/env node
 /**
- * 依相依關係推算每顆工作包的截止日。
+ * 依工作日與相依關係計算工作包的日期、CPM 與 PERT。
  *
- * 保證一件事：任一工作包的截止日都不早於它的先決工作包。人工排時程最常出現的
- * 矛盾就是前置工作比後續還晚到期，看板上看起來合理、實際上做不到。
- *
- * 這支腳本不碰 Gitea 也不碰 git，純算數字，所以沒有前置檢查、也不需要登入。
- * 算出來的日期交給 issue-update 逐顆寫上去。
- *
- * 日期以「日曆日」累加，不跳週末也不扣假日——跳過哪些日子是團隊政策，
- * 這裡不替使用者決定。
+ * 政府辦公日曆只影響日期，不影響人天估算；取不到某年度資料時仍會跳過週末，
+ * 並把警告寫到 stderr。輸出的日期採結束日不含在工期內，延續原本 dueDate 契約。
  *
  * 用法：node scripts/schedule.js --plan-file <計畫檔>
  *
  * 計畫檔格式：
  *   {
- *     "startDate": "2026-09-21",
+ *     "startDate": "2026-09-22",
  *     "workPackages": [
- *       { "index": 12, "title": "建立抽取契約", "days": 3, "depends": [11] }
+ *       { "index": 12, "title": "建立抽取契約", "days": 3, "depends": [11] },
+ *       {
+ *         "index": 13, "title": "驗證", "optimistic": 2,
+ *         "mostLikely": 3, "pessimistic": 5, "depends": [12]
+ *       }
  *     ]
  *   }
  */
 import { existsSync, readFileSync } from 'node:fs';
 import { ScriptError, main, parseFlags } from './lib.js';
 
+const CALENDAR_METADATA_URL = 'https://data.gov.tw/api/front/dataset/detail?nid=14718';
+const CALENDAR_URL_OVERRIDE = 'TEA_SDLC_CALENDAR_URL';
+const calendarCache = new Map();
+
 main(async () => {
   const flags = parseFlags(process.argv.slice(2), { required: ['plan-file'] });
   const plan = readPlan(flags['plan-file']);
-
   const order = topologicalOrder(plan.workPackages);
-  const dueByIndex = new Map();
-  const schedule = [];
+  const estimates = new Map(plan.workPackages.map((wp) => [wp.index, pertFor(wp)]));
+  const holidays = await loadHolidays(plan, order, estimates);
+  const schedule = buildSchedule(plan, order, estimates, holidays);
 
-  for (const index of order) {
-    const wp = plan.workPackages.find((item) => item.index === index);
-    // 從所有先決裡最晚的那一個接著做；沒有先決就從起始日開始
-    const readyFrom = (wp.depends ?? []).reduce(
-      (latest, dep) => (dueByIndex.get(dep) > latest ? dueByIndex.get(dep) : latest),
-      plan.startDate,
-    );
-    const dueDate = addDays(readyFrom, wp.days);
-    dueByIndex.set(index, dueDate);
-    schedule.push({ index, title: wp.title, days: wp.days, dueDate });
-  }
-
-  return { startDate: plan.startDate, order, schedule };
+  return {
+    startDate: plan.startDate,
+    order,
+    schedule: schedule.items,
+    criticalPath: schedule.criticalPath,
+    project: schedule.project,
+  };
 });
 
 function readPlan(planFile) {
@@ -59,7 +55,7 @@ function readPlan(planFile) {
     throw new ScriptError('BAD_PLAN', `${planFile} 不是合法的 JSON：${error.message}`);
   }
 
-  if (!/^\d{4}-\d{2}-\d{2}$/.test(plan.startDate ?? '')) {
+  if (!/^\d{4}-\d{2}-\d{2}$/.test(plan.startDate ?? '') || !validDate(plan.startDate)) {
     throw new ScriptError('BAD_PLAN', `startDate 需為 YYYY-MM-DD，收到的是 ${plan.startDate}`);
   }
   if (!Array.isArray(plan.workPackages) || plan.workPackages.length === 0) {
@@ -68,8 +64,7 @@ function readPlan(planFile) {
 
   const seen = new Set();
   for (const wp of plan.workPackages) {
-    // 同一個 index 出現兩次時，相依看的是後者、標題與人天卻取到前者，
-    // 算出來的時程會是兩份定義混出來的東西，而且完全不會報錯
+    // 同一個 index 出現兩次時，相依看的是後者、標題與人天卻取到前者。
     if (seen.has(wp.index)) {
       throw new ScriptError('BAD_PLAN', `工作包 #${wp.index} 在計畫裡出現了不只一次`);
     }
@@ -78,16 +73,48 @@ function readPlan(planFile) {
     if (!Number.isInteger(wp.index) || wp.index <= 0) {
       throw new ScriptError('BAD_PLAN', `工作包的 index 需為正整數，收到的是 ${wp.index}`);
     }
-    if (!Number.isFinite(wp.days) || wp.days <= 0) {
+    if (
+      wp.depends !== undefined &&
+      (!Array.isArray(wp.depends) || wp.depends.some((dep) => !Number.isInteger(dep)))
+    ) {
+      throw new ScriptError('BAD_PLAN', `工作包 #${wp.index} 的 depends 需為整數陣列`);
+    }
+    const estimate = pertFor(wp);
+    if (estimate === null && (!Number.isFinite(wp.days) || wp.days <= 0)) {
       throw new ScriptError('BAD_PLAN', `工作包 #${wp.index} 的 days 需為正數，收到的是 ${wp.days}`);
     }
   }
   return plan;
 }
 
+function pertFor(wp) {
+  const source = wp.pert ?? wp.estimates ?? wp;
+  const names = [
+    ['optimistic', 'mostLikely', 'pessimistic'],
+    ['optimisticDays', 'mostLikelyDays', 'pessimisticDays'],
+    ['o', 'm', 'p'],
+  ];
+  const fields = names.find(([o, m, p]) => [o, m, p].some((name) => source[name] !== undefined));
+  if (!fields) return null;
+
+  const [optimistic, mostLikely, pessimistic] = fields.map((name) => Number(source[name]));
+  if (
+    ![optimistic, mostLikely, pessimistic].every((value) => Number.isFinite(value) && value > 0) ||
+    optimistic > mostLikely ||
+    mostLikely > pessimistic
+  ) {
+    throw new ScriptError(
+      'BAD_PLAN',
+      `工作包 #${wp.index} 的 PERT 估算需為正數且符合 optimistic ≤ mostLikely ≤ pessimistic`,
+    );
+  }
+  const expected = (optimistic + 4 * mostLikely + pessimistic) / 6;
+  const variance = ((pessimistic - optimistic) / 6) ** 2;
+  return { optimistic, mostLikely, pessimistic, expected, variance };
+}
+
 /**
- * 拓撲排序：先決一定排在後續之前。
- * 用 Kahn 演算法——排不完就代表有環，而環上的成員正是排不進去的那些。
+ * 拓撲排序：先決一定排在後續之前。排不完就代表有環。
  */
 function topologicalOrder(workPackages) {
   const known = new Set(workPackages.map((wp) => wp.index));
@@ -130,9 +157,216 @@ function topologicalOrder(workPackages) {
   return order;
 }
 
-/** 在 YYYY-MM-DD 上加幾個日曆日，回傳同樣格式 */
-function addDays(date, days) {
+async function loadHolidays(plan, order, estimates) {
+  const totalDays = order.reduce((total, index) => {
+    const wp = plan.workPackages.find((item) => item.index === index);
+    return total + Math.ceil(estimates.get(index)?.expected ?? wp.days);
+  }, 0);
+  const lastDate = addCalendarDays(plan.startDate, totalDays + 366);
+  const years = [];
+  for (let year = yearOf(plan.startDate); year <= yearOf(lastDate); year += 1) years.push(year);
+
+  const holidays = new Map();
+  for (const year of years) holidays.set(year, await holidaysForYear(year));
+  return holidays;
+}
+
+async function holidaysForYear(year) {
+  if (calendarCache.has(year)) return calendarCache.get(year);
+
+  try {
+    const url = process.env[CALENDAR_URL_OVERRIDE]?.trim() || (await calendarResourceUrl(year));
+    const response = await fetch(url, { signal: AbortSignal.timeout(10_000) });
+    if (!response.ok) throw new Error(`HTTP ${response.status}`);
+    const holidays = parseCalendar(await response.text(), year);
+    calendarCache.set(year, holidays);
+    return holidays;
+  } catch (error) {
+    const fallback = new Set();
+    calendarCache.set(year, fallback);
+    console.error(`警告：無法取得 ${year} 年台灣辦公日曆（${error.message}），改以週末作為非工作日`);
+    return fallback;
+  }
+}
+
+async function calendarResourceUrl(year) {
+  const response = await fetch(CALENDAR_METADATA_URL, { signal: AbortSignal.timeout(10_000) });
+  if (!response.ok) throw new Error(`日曆中繼資料 HTTP ${response.status}`);
+  const body = await response.json();
+  const rocYear = year - 1911;
+  const resources = body.payload?.resources ?? [];
+  const resource = [...resources].reverse().find(
+    (item) =>
+      item.file_format?.toUpperCase() === 'CSV' &&
+      item.description?.startsWith(`${rocYear}年`) &&
+      item.description.includes('政府行政機關辦公日曆表') &&
+      !item.description.includes('Google'),
+  );
+  if (!resource?.url) throw new Error(`資料集沒有 ${year} 年 CSV`);
+  return resource.url;
+}
+
+function parseCalendar(text, year) {
+  const lines = text.replace(/^\uFEFF/, '').split(/\r?\n/).filter((line) => line.trim() !== '');
+  if (lines.length < 2) throw new Error('日曆 CSV 沒有資料');
+  const header = parseCsvLine(lines[0]).map((field) => field.trim());
+  const dateColumn = header.indexOf('西元日期');
+  const holidayColumn = header.indexOf('是否放假');
+  if (dateColumn < 0 || holidayColumn < 0) throw new Error('日曆 CSV 缺少必要欄位');
+
+  const holidays = new Set();
+  for (const line of lines.slice(1)) {
+    const fields = parseCsvLine(line);
+    const date = fields[dateColumn]?.trim();
+    const holiday = fields[holidayColumn]?.trim();
+    if (/^\d{8}$/.test(date) && Number(date.slice(0, 4)) === year && holiday !== '0') {
+      holidays.add(`${date.slice(0, 4)}-${date.slice(4, 6)}-${date.slice(6, 8)}`);
+    }
+  }
+  return holidays;
+}
+
+function parseCsvLine(line) {
+  const fields = [];
+  let field = '';
+  let quoted = false;
+  for (let i = 0; i < line.length; i += 1) {
+    const char = line[i];
+    if (char === '"' && line[i + 1] === '"' && quoted) {
+      field += '"';
+      i += 1;
+    } else if (char === '"') {
+      quoted = !quoted;
+    } else if (char === ',' && !quoted) {
+      fields.push(field);
+      field = '';
+    } else {
+      field += char;
+    }
+  }
+  fields.push(field);
+  return fields;
+}
+
+function buildSchedule(plan, order, estimates, holidays) {
+  const byIndex = new Map(plan.workPackages.map((wp) => [wp.index, wp]));
+  const early = new Map();
+  for (const index of order) {
+    const wp = byIndex.get(index);
+    const duration = Math.ceil(estimates.get(index)?.expected ?? wp.days);
+    const ES = (wp.depends ?? []).reduce(
+      (latest, dep) => (early.get(dep).EF > latest ? early.get(dep).EF : latest),
+      plan.startDate,
+    );
+    const EF = addWorkdays(ES, duration, holidays);
+    early.set(index, { ES, EF, duration });
+  }
+
+  const projectFinish = [...early.values()].reduce(
+    (latest, item) => (item.EF > latest ? item.EF : latest),
+    plan.startDate,
+  );
+  const successors = new Map(order.map((index) => [index, []]));
+  for (const wp of plan.workPackages) {
+    for (const dep of wp.depends ?? []) successors.get(dep).push(wp.index);
+  }
+
+  const late = new Map();
+  for (const index of [...order].reverse()) {
+    const { duration } = early.get(index);
+    const successorStarts = successors.get(index).map((successor) => late.get(successor).LS);
+    const LF = successorStarts.length === 0 ? projectFinish : successorStarts.reduce(minDate);
+    const LS = subtractWorkdays(LF, duration, holidays);
+    late.set(index, { LS, LF });
+  }
+
+  const items = order.map((index) => {
+    const wp = byIndex.get(index);
+    const estimate = estimates.get(index);
+    const { ES, EF, duration } = early.get(index);
+    const { LS, LF } = late.get(index);
+    const float = workdayDistance(ES, LS, holidays);
+    return {
+      index,
+      title: wp.title,
+      days: wp.days,
+      dueDate: EF,
+      ES,
+      EF,
+      LS,
+      LF,
+      float,
+      critical: float === 0,
+      expectedDays: estimate?.expected ?? wp.days,
+      ...(estimate ? { pert: estimate } : {}),
+    };
+  });
+  const criticalPath = items.filter((item) => item.critical).map((item) => item.index);
+  const variance = items.reduce((total, item) => total + (item.pert?.variance ?? 0), 0);
+  const expectedDuration = items.reduce((total, item) => total + (item.pert?.expected ?? item.days), 0);
+  return {
+    items,
+    criticalPath,
+    project: {
+      finishDate: projectFinish,
+      expectedDuration,
+      variance,
+      standardDeviation: Math.sqrt(variance),
+    },
+  };
+}
+
+function addWorkdays(date, days, holidays) {
+  let current = date;
+  let remaining = days;
+  while (remaining > 0) {
+    current = addCalendarDays(current, 1);
+    if (isWorkday(current, holidays)) remaining -= 1;
+  }
+  return current;
+}
+
+function subtractWorkdays(date, days, holidays) {
+  let current = date;
+  let remaining = days;
+  while (remaining > 0) {
+    current = addCalendarDays(current, -1);
+    if (isWorkday(current, holidays)) remaining -= 1;
+  }
+  return current;
+}
+
+function workdayDistance(start, end, holidays) {
+  if (start === end) return 0;
+  let current = start;
+  let distance = 0;
+  while (current < end) {
+    current = addCalendarDays(current, 1);
+    if (isWorkday(current, holidays)) distance += 1;
+  }
+  return distance;
+}
+
+function isWorkday(date, holidays) {
+  const day = new Date(`${date}T00:00:00Z`).getUTCDay();
+  return day !== 0 && day !== 6 && !holidays.get(yearOf(date))?.has(date);
+}
+
+function minDate(a, b) {
+  return a < b ? a : b;
+}
+
+function addCalendarDays(date, days) {
   const moment = new Date(`${date}T00:00:00Z`);
   moment.setUTCDate(moment.getUTCDate() + days);
   return moment.toISOString().slice(0, 10);
 }
+
+function validDate(date) {
+  const moment = new Date(`${date}T00:00:00Z`);
+  return !Number.isNaN(moment.valueOf()) && moment.toISOString().slice(0, 10) === date;
+}
+
+function yearOf(date) {
+  return Number(date.slice(0, 4));
+}