VeggieRadar 🥬

Today's Taiwan wholesale vegetable & fruit prices, at a glance — plus an estimated traditional-market retail band so you can sanity-check a stall's price while standing in front of it. Open the app and immediately see a calm, MUJI-inspired board of the produce people buy most — green when cheaper, clay when pricier, priced per catty (台斤).

Three questions the board answers without typing: what does this cost today, is that cheap for this crop (against its own recent norm), and which variety am I actually being quoted when one crop trades at two very different prices.

• Audience: shoppers at traditional markets and home cooks, primarily on phones.
• Experience: board-first and mobile-first. No typing required — the common produce board loads instantly; search is secondary.
• Zero-cost stack: GitHub Pages frontend + Google Apps Script backend, sourced from the Taiwan Ministry of Agriculture (MOA) open data. No paid services.

Note on language: the UI is in Traditional Chinese (its audience); code, comments, and this documentation are in English.

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1. Design principles

• Board-first, no typing. The home screen lists ~100 defined items as large, calm rows — scan and go. Out-of-season crops return no data and drop out automatically, so a typical day shows ~90.
• Per-catty pricing. Primary price is 元/台斤 (the market convention; 1 catty = 600 g). The MOA source is 元/公斤, converted on the client (×0.6).
• Lead with the price you pay; keep the fact underneath. The headline number is the estimated traditional-market price (約 44 元/台斤) — that is what a shopper transacts at. The measured wholesale closing average and the reference band sit under it (市場 35–55・批發 14.6), and the drawer shows the markup the estimate adds. The estimate is never presented as a quoted price — see §4. Comparisons ranked for the shopper (「同類更划算的選擇」) use the same market basis, because a crop that is cheaper at auction can be dearer at the stall.
• The change badge is wholesale. ↓ 7.0% tracks the wholesale average, the only measured series, and is labelled 批發較昨日 in the drawer. The band is rounded to NT$5, so it would read as frozen against small real moves.
• Colour as meaning. Sage ↓ 便宜了 (cheaper), clay ↑ 變貴了 (pricier), grey → 持平 (flat), compared with the previous trading day. Arrows + text back up the colour so it never relies on colour alone.
• Honest freshness. A caption shows the data date and that it is the wholesale closing average — wholesale prices publish after market close, so the latest day with real trades is shown.
• "Cheaper than yesterday" and "cheap for this crop" are different questions. ↓ 7.0% compares with the previous trading day. The sage badge 「比近月便宜 23%」 compares today's wholesale price with the median of that crop's own last 28 trading days, and 「划算優先」 sorts the board by it so the day's real bargains sit on top. Only the discount side gets a badge — the change column already covers the pricier side. See §5.
• A blended average can match no stall. When varieties inside one crop diverge (綠竹筍 at 2.5× 麻竹筍), the drawer decomposes the wholesale number per variety instead of pretending the average is a price. See §5.
• Degrade honestly, never blankly. The last good board is kept in localStorage: when the backend is unreachable the app serves those prices with 「目前連不上伺服器」 plus a retry, because stale prices beat a blank page in front of a stall. The retry keeps them too — it holds whatever is on screen rather than re-reading the cache, since a stale mirror is painted without being cached and re-reading answered null for the very board being read (#78). A busy backend during search says 「服務忙碌中」 — never 「查無此品項」, which would be a lie about the produce rather than about us.
• Shareable. Every screen is a URL. The item drawer, a search, the filter and the sort all live in the hash (#/i/高麗菜, #/?f=葉菜類&sort=value), because the way this board spreads is one shopper pasting today's price into a LINE group — and a link that opens the home screen instead of that price is not worth pasting. The drawer is a history entry too, so the Android back key closes it rather than leaving the app; a link to a crop that is out of season today says 「今日無交易資料」 and lands on the board instead of erroring. A typed word reaches the hash once its debounce settles — one word, not one keystroke, and with replaceState, so the board you are looking at is always the board your URL describes without typing filling up the back button.
• MUJI aesthetic. Paper background, ink text, hairline dividers, generous whitespace, restrained type. No loud colour, no heavy shadows.

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2. Architecture

MOA open-data API ──▶ GAS refresh (4-hourly trigger) ──▶ CacheService + chunked
  (single-date and       board   → the day's prices              ScriptProperties
   range queries)        history → 28 trading days → baseline (§5)
                                                                      │
                                                            GET /exec │
                                                                      ▼
Frontend (GitHub Pages) ◀── validate ◀── GitHub Actions (deploy-pages)
  data/board.json, published                 runs when a crawl lands (the
  inside the bundle's own artifact           backend dispatches it), on
        │                                    push, and 2-hourly as fallback
        ▼
Browser: localStorage (paints first) ──▶ data/board.json ──▶ GAS /exec
                                         authoritative          only when the mirror
                                         while < 6 h old        is stale or missing

This is the beginning of the README. Read the rest at the original. Read the full README ↗