1 files changed, 118 insertions, 0 deletions
diff --git a/app/routes/api.events.$id.ics.ts b/app/routes/api.events.$id.ics.ts
new file mode 100644
index 0000000..c11f9ff
--- /dev/null
+++ b/app/routes/api.events.$id.ics.ts
@@ -0,0 +1,118 @@
+import { getEvent } from "~/lib/db.server";
+import type { Route } from "./+types/api.events.$id.ics";
+import type { Event } from "~/lib/db.server";
+
+export async function loader({ params }: Route.LoaderArgs) {
+  const id = parseInt(params.id, 10);
+  if (isNaN(id)) throw new Response("Not Found", { status: 404 });
+  const event = getEvent(id);
+  if (!event) throw new Response("Not Found", { status: 404 });
+
+  return new Response(buildIcs(event), {
+    headers: {
+      "Content-Type": "text/calendar; charset=utf-8",
+      "Content-Disposition": `attachment; filename="event-${id}.ics"`,
+      "Cache-Control": "no-cache",
+    },
+  });
+}
+
+function buildIcs(event: Event): string {
+  const uid = `event-${event.id}@tokyo-livehouse-events`;
+  const dtstamp = toIcsDateTime(new Date());
+
+  let dtstart: string;
+  let dtend: string;
+
+  if (event.start_time && /^\d{1,2}:\d{2}/.test(event.start_time)) {
+    const [h, m] = event.start_time.split(":").map(Number);
+    const [y, mo, d] = event.date.split("-").map(Number);
+    // Floating time (no timezone suffix) — display in user's local time
+    const pad = (n: number) => String(n).padStart(2, "0");
+    const startStr = `${event.date.replace(/-/g, "")}T${pad(h)}${pad(m)}00`;
+    // End time = start + 2 hours
+    const endH = h + 2;
+    const endStr =
+      endH < 24
+        ? `${event.date.replace(/-/g, "")}T${pad(endH)}${pad(m)}00`
+        : (() => {
+            const next = new Date(y, mo - 1, d + 1);
+            return (
+              `${next.getFullYear()}${pad(next.getMonth() + 1)}${pad(next.getDate())}` +
+              `T${pad(endH - 24)}${pad(m)}00`
+            );
+          })();
+    dtstart = `DTSTART:${startStr}`;
+    dtend = `DTEND:${endStr}`;
+  } else {
+    // All-day event
+    const [y, mo, d] = event.date.split("-").map(Number);
+    const next = new Date(y, mo - 1, d + 1);
+    const pad = (n: number) => String(n).padStart(2, "0");
+    const nextStr = `${next.getFullYear()}${pad(next.getMonth() + 1)}${pad(next.getDate())}`;
+    dtstart = `DTSTART;VALUE=DATE:${event.date.replace(/-/g, "")}`;
+    dtend = `DTEND;VALUE=DATE:${nextStr}`;
+  }
+
+  const descParts: string[] = [];
+  if (event.artist) descParts.push(`出演: ${event.artist}`);
+  if (event.open_time) descParts.push(`OPEN: ${event.open_time}`);
+  if (event.start_time) descParts.push(`START: ${event.start_time}`);
+  if (event.price) descParts.push(`料金: ${event.price}`);
+  if (event.source_url) descParts.push(`詳細: ${event.source_url}`);
+  if (event.ticket_url) descParts.push(`チケット: ${event.ticket_url}`);
+
+  const location = [event.venue_name, event.venue_area].filter(Boolean).join(" ");
+
+  const lines: string[] = [
+    "BEGIN:VCALENDAR",
+    "VERSION:2.0",
+    "PRODID:-//Tokyo Livehouse Events//JA",
+    "CALSCALE:GREGORIAN",
+    "METHOD:PUBLISH",
+    "BEGIN:VEVENT",
+    `UID:${uid}`,
+    `DTSTAMP:${dtstamp}`,
+    dtstart,
+    dtend,
+    foldLine(`SUMMARY:${escIcs(event.title)}`),
+    foldLine(`LOCATION:${escIcs(location)}`),
+  ];
+
+  if (descParts.length > 0) {
+    lines.push(foldLine(`DESCRIPTION:${escIcs(descParts.join("\\n"))}`));
+  }
+
+  if (event.source_url) {
+    lines.push(`URL:${event.source_url}`);
+  }
+
+  lines.push("END:VEVENT", "END:VCALENDAR");
+
+  return lines.join("\r\n") + "\r\n";
+}
+
+function escIcs(s: string): string {
+  return s.replace(/\\/g, "\\\\").replace(/;/g, "\\;").replace(/,/g, "\\,");
+}
+
+// Fold lines longer than 75 chars (RFC 5545 §3.1)
+function foldLine(line: string): string {
+  if (line.length <= 75) return line;
+  const chunks: string[] = [];
+  let pos = 0;
+  while (pos < line.length) {
+    const limit = pos === 0 ? 75 : 74;
+    chunks.push((pos === 0 ? "" : " ") + line.slice(pos, pos + limit));
+    pos += limit;
+  }
+  return chunks.join("\r\n");
+}
+
+function toIcsDateTime(d: Date): string {
+  const pad = (n: number) => String(n).padStart(2, "0");
+  return (
+    `${d.getUTCFullYear()}${pad(d.getUTCMonth() + 1)}${pad(d.getUTCDate())}` +
+    `T${pad(d.getUTCHours())}${pad(d.getUTCMinutes())}${pad(d.getUTCSeconds())}Z`
+  );
+}