schedule: 日付解析を共通モジュールに切り出し

- src/lib/schedule-dates.ts に parseDates などを移動
- カレンダー（ブラウザ）とビルド時の月別ページの両方から使えるようにした
- 挙動は変わっていない（カレンダーのマーク・終了判定・日別予定のスナップショット比較で一致）

2 files changed, 131 insertions, 112 deletions

diff --git a/src/components/ScheduleInteractive.astro b/src/components/ScheduleInteractive.astro
index 8c14f38..3dd6048 100644
--- a/src/components/ScheduleInteractive.astro
+++ b/src/components/ScheduleInteractive.astro
@@ -1,6 +1,7 @@
 <script>
   // URLは src/data/schedule/config.ts で一元管理している（ページ移転時はそこだけ変える）
   import { scheduleAbsoluteUrl } from '@/data/schedule/config';
+  import { parseDates, applyExclusions, toKey, keyToDate } from '@/lib/schedule-dates';
 
   const CATEGORY_DEFS = [
     { icon: '👶', label: '子育て' },
@@ -23,121 +24,9 @@
   const isLibrary = (e: { source?: string }) =>
     (e.source ?? '').includes('library.kodaira.ed.jp/viewer/info.html');
   const WEEKDAYS = ['日', '月', '火', '水', '木', '金', '土'];
-  const WEEKDAY_MAP = { 日: 0, 月: 1, 火: 2, 水: 3, 木: 4, 金: 5, 土: 6 };
-
-  const normalizeDigits = (s) =>
-    s.replace(/[０-９]/g, (c) => String.fromCharCode(c.charCodeAt(0) - 0xfee0));
-  const pad2 = (n) => String(n).padStart(2, '0');
-  const toKey = (y, m, d) => `${y}-${pad2(m)}-${pad2(d)}`;
-  const keyToDate = (key) => {
-    const [y, m, d] = key.split('-').map(Number);
-    return new Date(y, m - 1, d);
-  };
   const escapeHtml = (s) =>
     s.replace(/[&<>"']/g, (c) => ({ '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;' }[c]));
 
-  function applyExclusions(dateSet, raw) {
-    const text = normalizeDigits(raw);
-    const re = /(\d{1,2})月(\d{1,2})日を除く/g;
-    let m;
-    while ((m = re.exec(text)) !== null) {
-      const month = Number(m[1]);
-      const day = Number(m[2]);
-      const year = text.slice(0, m.index).includes('令和9年') ? 2027 : month === 1 ? 2027 : 2026;
-      dateSet.delete(toKey(year, month, day));
-    }
-  }
-
-  // 日付セル・時間セルから YYYY-MM-DD を抽出する。
-  // 期間は、7日以内なら全日、曜日指定があればその曜日、それ以外は開始日と終了日を拾う。
-  function parseDates(raw) {
-    const text = normalizeDigits(raw);
-    const dates = new Set();
-    const add = (y, m, d) => {
-      if (y && m >= 1 && m <= 12 && d >= 1 && d <= 31) dates.add(toKey(y, m, d));
-    };
-    const yearFor = (index, month) => {
-      if (text.slice(0, index).includes('令和9年')) return 2027;
-      return month === 1 ? 2027 : 2026;
-    };
-
-    let m;
-    const rangeRe = /(\d{1,2})月(\d{1,2})日[^〜]*〜\s*(?:(\d{1,2})月)?(\d{1,2})日/g;
-    while ((m = rangeRe.exec(text)) !== null) {
-      const startMonth = Number(m[1]);
-      const startDay = Number(m[2]);
-      const endMonth = m[3] ? Number(m[3]) : startMonth;
-      const endDay = Number(m[4]);
-      const startYear = yearFor(m.index, startMonth);
-      const endYear = startYear + (endMonth < startMonth ? 1 : 0);
-      const start = new Date(startYear, startMonth - 1, startDay);
-      const end = new Date(endYear, endMonth - 1, endDay);
-      if (end < start) continue;
-
-      const lengthDays = Math.round((end - start) / 86400000) + 1;
-      const after = text.slice(m.index + m[0].length);
-      let weekdays = null;
-
-      const noWeek = after.match(/の([月火水木金土日])曜日/);
-      if (noWeek) {
-        weekdays = [WEEKDAY_MAP[noWeek[1]]];
-      } else {
-        const group = after.match(/（([月火水木金土日](?:・[月火水木金土日])*)）/);
-        const hasStartWeekday = new RegExp(`${startMonth}月${startDay}日（[月火水木金土日]`).test(text);
-        if (group && (group[1].includes('・') || !hasStartWeekday)) {
-          weekdays = group[1].split('・').map((w) => WEEKDAY_MAP[w]);
-        } else {
-          const startWeek = text.match(new RegExp(`${startMonth}月${startDay}日（([月火水木金土日])`));
-          const endWeek = text.match(new RegExp(`(?:${endMonth}月)?${endDay}日（([月火水木金土日])`));
-          if (startWeek && endWeek && startWeek[1] === endWeek[1]) {
-            weekdays = [WEEKDAY_MAP[startWeek[1]]];
-          }
-        }
-      }
-
-      if (lengthDays <= 7 || (!weekdays && lengthDays <= 14)) {
-        for (let d = new Date(start); d <= end; d.setDate(d.getDate() + 1)) {
-          add(d.getFullYear(), d.getMonth() + 1, d.getDate());
-        }
-      } else if (weekdays) {
-        for (let d = new Date(start); d <= end; d.setDate(d.getDate() + 1)) {
-          if (weekdays.includes(d.getDay())) add(d.getFullYear(), d.getMonth() + 1, d.getDate());
-        }
-      } else {
-        add(start.getFullYear(), start.getMonth() + 1, start.getDate());
-        add(end.getFullYear(), end.getMonth() + 1, end.getDate());
-      }
-    }
-
-    const fullDates = [];
-    const fullRe = /(\d{1,2})月(\d{1,2})日/g;
-    while ((m = fullRe.exec(text)) !== null) {
-      const month = Number(m[1]);
-      const day = Number(m[2]);
-      fullDates.push({ index: m.index, month });
-      add(yearFor(m.index, month), month, day);
-    }
-
-    const bareRe = /(\d{1,2})日/g;
-    while ((m = bareRe.exec(text)) !== null) {
-      const index = m.index;
-      if (index > 0 && text[index - 1] === '月') continue;
-      let previous = null;
-      for (const fd of fullDates) {
-        if (fd.index < index) previous = fd;
-        else break;
-      }
-      if (!previous) continue;
-      const day = Number(m[1]);
-      add(yearFor(index, previous.month), previous.month, day);
-    }
-
-    // 「（11月4日を除く）」などの除外日を反映する。
-    applyExclusions(dates, text);
-
-    return [...dates].sort();
-  }
-
   function initSchedule() {
     const calendarEl = document.getElementById('schedule-calendar');
     const detailsEl = document.getElementById('schedule-day-details');
diff --git a/src/lib/schedule-dates.ts b/src/lib/schedule-dates.ts
new file mode 100644
index 0000000..5f0900b
--- /dev/null
+++ b/src/lib/schedule-dates.ts
@@ -0,0 +1,130 @@
+// 行事予定の日付解析（ブラウザとビルド時の両方で使う）。
+//
+// 日付セルには「11月1日（日）」「11月1日・18日、12月6日」「10月24日（土）〜11月22日（日）」
+// 「11月2日〜12月14日の月曜日」など、さまざまな書き方がある。
+// ここでは、それらから YYYY-MM-DD を組み立てる。
+
+export const WEEKDAY_MAP: Record<string, number> = {
+  日: 0,
+  月: 1,
+  火: 2,
+  水: 3,
+  木: 4,
+  金: 5,
+  土: 6,
+};
+
+export const normalizeDigits = (s: string) =>
+  s.replace(/[０-９]/g, (c) => String.fromCharCode(c.charCodeAt(0) - 0xfee0));
+
+export const pad2 = (n: number) => String(n).padStart(2, '0');
+
+export const toKey = (y: number, m: number, d: number) => `${y}-${pad2(m)}-${pad2(d)}`;
+
+export const keyToDate = (key: string) => {
+  const [y, m, d] = key.split('-').map(Number);
+  return new Date(y, m - 1, d);
+};
+
+/** 「（11月4日を除く）」などの除外日を、日付の集合から取り除く */
+export function applyExclusions(dateSet: Set<string>, raw: string) {
+  const text = normalizeDigits(raw);
+  const re = /(\d{1,2})月(\d{1,2})日を除く/g;
+  let m;
+  while ((m = re.exec(text)) !== null) {
+    const month = Number(m[1]);
+    const day = Number(m[2]);
+    const year = text.slice(0, m.index).includes('令和9年') ? 2027 : month === 1 ? 2027 : 2026;
+    dateSet.delete(toKey(year, month, day));
+  }
+}
+
+// 日付セル・時間セルから YYYY-MM-DD を抽出する。
+// 期間は、7日以内なら全日、曜日指定があればその曜日、それ以外は開始日と終了日を拾う。
+export function parseDates(raw: string): string[] {
+  const text = normalizeDigits(raw);
+  const dates = new Set<string>();
+  const add = (y: number, m: number, d: number) => {
+    if (y && m >= 1 && m <= 12 && d >= 1 && d <= 31) dates.add(toKey(y, m, d));
+  };
+  const yearFor = (index: number, month: number) => {
+    if (text.slice(0, index).includes('令和9年')) return 2027;
+    return month === 1 ? 2027 : 2026;
+  };
+
+  let m;
+  const rangeRe = /(\d{1,2})月(\d{1,2})日[^〜]*〜\s*(?:(\d{1,2})月)?(\d{1,2})日/g;
+  while ((m = rangeRe.exec(text)) !== null) {
+    const startMonth = Number(m[1]);
+    const startDay = Number(m[2]);
+    const endMonth = m[3] ? Number(m[3]) : startMonth;
+    const endDay = Number(m[4]);
+    const startYear = yearFor(m.index, startMonth);
+    const endYear = startYear + (endMonth < startMonth ? 1 : 0);
+    const start = new Date(startYear, startMonth - 1, startDay);
+    const end = new Date(endYear, endMonth - 1, endDay);
+    if (end < start) continue;
+
+    const lengthDays = Math.round((end.getTime() - start.getTime()) / 86400000) + 1;
+    const after = text.slice(m.index + m[0].length);
+    let weekdays: number[] | null = null;
+
+    const noWeek = after.match(/の([月火水木金土日])曜日/);
+    if (noWeek) {
+      weekdays = [WEEKDAY_MAP[noWeek[1]]];
+    } else {
+      const group = after.match(/（([月火水木金土日](?:・[月火水木金土日])*)）/);
+      const hasStartWeekday = new RegExp(`${startMonth}月${startDay}日（[月火水木金土日]`).test(text);
+      if (group && (group[1].includes('・') || !hasStartWeekday)) {
+        weekdays = group[1].split('・').map((w) => WEEKDAY_MAP[w]);
+      } else {
+        const startWeek = text.match(new RegExp(`${startMonth}月${startDay}日（([月火水木金土日])`));
+        const endWeek = text.match(new RegExp(`(?:${endMonth}月)?${endDay}日（([月火水木金土日])`));
+        if (startWeek && endWeek && startWeek[1] === endWeek[1]) {
+          weekdays = [WEEKDAY_MAP[startWeek[1]]];
+        }
+      }
+    }
+
+    if (lengthDays <= 7 || (!weekdays && lengthDays <= 14)) {
+      for (let d = new Date(start); d <= end; d.setDate(d.getDate() + 1)) {
+        add(d.getFullYear(), d.getMonth() + 1, d.getDate());
+      }
+    } else if (weekdays) {
+      for (let d = new Date(start); d <= end; d.setDate(d.getDate() + 1)) {
+        if (weekdays.includes(d.getDay())) add(d.getFullYear(), d.getMonth() + 1, d.getDate());
+      }
+    } else {
+      add(start.getFullYear(), start.getMonth() + 1, start.getDate());
+      add(end.getFullYear(), end.getMonth() + 1, end.getDate());
+    }
+  }
+
+  const fullDates: { index: number; month: number }[] = [];
+  const fullRe = /(\d{1,2})月(\d{1,2})日/g;
+  while ((m = fullRe.exec(text)) !== null) {
+    const month = Number(m[1]);
+    const day = Number(m[2]);
+    fullDates.push({ index: m.index, month });
+    add(yearFor(m.index, month), month, day);
+  }
+
+  const bareRe = /(\d{1,2})日/g;
+  while ((m = bareRe.exec(text)) !== null) {
+    const index = m.index;
+    if (index > 0 && text[index - 1] === '月') continue;
+    let previous: { index: number; month: number } | null = null;
+    for (const fd of fullDates) {
+      if (fd.index < index) previous = fd;
+      else break;
+    }
+    if (!previous) continue;
+    const day = Number(m[1]);
+    add(yearFor(index, previous.month), previous.month, day);
+  }
+
+  // 「（11月4日を除く）」などの除外日を反映する。
+  applyExclusions(dates, text);
+
+  return [...dates].sort();
+}