Initial commit: postcard v1

Phone photo -> composited postcard (canvas templates, stamp corner,
EXIF-aware date/location, self-hosted handwriting font) with a small
server for share links, day-context caption drafting off goonk's
day-summary API, and Nominatim reverse geocoding.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

server/src/routes.js

@@ -0,0 +1,133 @@
+import { Router } from 'express'
+import fs from 'node:fs'
+import { config } from './config.js'
+import { db, blobPath } from './db.js'
+import { newPostcardId } from './ids.js'
+import { checkRateLimit } from './ratelimit.js'
+import { draftCaption } from './caption.js'
+import { reverseGeocode } from './geocode.js'
+
+export const apiRouter = Router()
+export const imageRouter = Router()
+
+const ALLOWED_MIME = new Set(['image/jpeg', 'image/png', 'image/webp'])
+
+// GET /api/caption?date=YYYY-MM-DD — draft a one-line caption from that
+// day's context. Editable client-side before it's ever composited in.
+apiRouter.get('/caption', async (req, res) => {
+  const date = /^\d{4}-\d{2}-\d{2}$/.test(req.query.date) ? req.query.date : new Date().toISOString().slice(0, 10)
+  const caption = await draftCaption(date)
+  res.json({ caption })
+})
+
+// GET /api/geocode?lat=&lon= — "City, Country" for the stamp corner's
+// location line, only ever called when the uploaded photo had EXIF GPS.
+// Proxied server-side so the client never talks to Nominatim directly
+// (keeps the 1req/sec throttling and User-Agent policy in one place).
+apiRouter.get('/geocode', async (req, res) => {
+  const lat = Number(req.query.lat)
+  const lon = Number(req.query.lon)
+  if (!Number.isFinite(lat) || !Number.isFinite(lon)) {
+    res.status(400).json({ error: 'lat and lon required' })
+    return
+  }
+  const label = await reverseGeocode(lat, lon)
+  res.json({ label })
+})
+
+apiRouter.post('/upload', (req, res) => {
+  const ip = req.ip
+  if (!checkRateLimit(ip)) {
+    res.status(429).json({ error: 'too many uploads, try again later' })
+    return
+  }
+
+  const mime = (req.get('Content-Type') || '').split(';')[0].trim()
+  if (!ALLOWED_MIME.has(mime)) {
+    res.status(415).json({ error: 'unsupported image type' })
+    return
+  }
+
+  const contentLength = Number(req.get('Content-Length') ?? 0)
+  if (contentLength > config.maxUploadBytes) {
+    res.status(413).json({ error: 'file too large' })
+    return
+  }
+
+  const id = newPostcardId()
+  const dest = blobPath(id)
+  const writeStream = fs.createWriteStream(dest, { flags: 'wx' })
+
+  let bytesReceived = 0
+  let aborted = false
+
+  req.on('data', chunk => {
+    bytesReceived += chunk.length
+    if (bytesReceived > config.maxUploadBytes) {
+      aborted = true
+      writeStream.destroy()
+      req.destroy()
+    }
+  })
+
+  req.pipe(writeStream)
+
+  writeStream.on('error', () => {
+    fs.rm(dest, { force: true }, () => {})
+    if (!res.headersSent) res.status(500).json({ error: 'write failed' })
+  })
+
+  writeStream.on('finish', () => {
+    if (aborted) {
+      fs.rm(dest, { force: true }, () => {})
+      if (!res.headersSent) res.status(413).json({ error: 'file too large' })
+      return
+    }
+
+    const now = Math.floor(Date.now() / 1000)
+    const expiresAt = now + config.ttlHours * 3600
+
+    db.prepare(
+      `INSERT INTO postcards (id, blob_path, mime, created_at, expires_at) VALUES (?, ?, ?, ?, ?)`,
+    ).run(id, dest, mime, now, expiresAt)
+
+    res.json({ id, url: `/p/${id}` })
+  })
+})
+
+// No develop-later gate — this app's whole point is immediacy, unlike latent.
+imageRouter.get('/p/:id', (req, res) => {
+  const postcard = db.prepare(`SELECT * FROM postcards WHERE id = ?`).get(req.params.id)
+  const now = Math.floor(Date.now() / 1000)
+
+  if (!postcard || postcard.expires_at < now || !fs.existsSync(postcard.blob_path)) {
+    res.status(404).send(renderPage('not found', '<p>this one\'s gone — wrong link, or it already expired.</p>'))
+    return
+  }
+
+  res.setHeader('Content-Type', postcard.mime)
+  res.setHeader('Cache-Control', 'public, max-age=31536000, immutable')
+  fs.createReadStream(postcard.blob_path).pipe(res)
+})
+
+function escapeHtml(s) {
+  return s.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;')
+}
+
+function renderPage(title, bodyHtml) {
+  return `<!doctype html>
+<html lang="en">
+<head>
+  <meta charset="utf-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1">
+  <title>postcard &mdash; ${escapeHtml(title)}</title>
+  <link rel="stylesheet" href="/style.css">
+</head>
+<body>
+  <div id="app">
+    <div class="header-row"><h1>postcard</h1></div>
+    <div class="card">${bodyHtml}</div>
+  </div>
+</body>
+</html>`
+}