bincio-activity/CLAUDE.md

# BincioActivity — Context for Claude

## What this project is

BincioActivity is a federated, open-source, self-hosted activity stats platform
(think personal Strava). Two-stage pipeline:

1. **`bincio extract`** (Python): GPX/FIT/TCX → BAS JSON data store
2. **`bincio render`** (Astro/Node): BAS data store → static website

The BAS (BincioActivity Schema) JSON files are the federation protocol.
Anyone can publish their data as BAS JSON and others can include it.

## Key design decisions

- **No database, no server** — everything is static files
- **Python with uv** for the extract stage
- **Astro + Svelte + Tailwind + MapLibre GL + Observable Plot** for the site
- **Haversine** (not geopy) for distance calculations (10x faster)
- **Worker initializer pattern** for ProcessPoolExecutor — large shared data
  (strava_lookup dict, known_hashes frozenset) is sent once per worker via
  `initializer=`, not once per task
- **BAS activity IDs** always use UTC with Z suffix for URL safety
- **TCX files** from Garmin use both `http://` and `https://` namespace URIs —
  parser handles both

## User's data

- Source: `~/src/cycling_data_davide/`
  - `activities/` — Strava export (GPX, FIT, TCX, all with .gz variants)
  - `Karoo_2026/` — recent Karoo device FIT files
  - `Karoo/` — older Karoo FIT files
  - `activities.csv` — Strava metadata (names, descriptions, gear)
- Extracted output: `~/bincio_data/` (or `/tmp/bincio_test/` for testing)
- ~3,200 input files → ~2,082 unique activities after dedup
- Date range: 2014–2026

## Project structure

```
bincio/                    Python package
  extract/
    models.py              DataPoint, ParsedActivity, LapData
    parsers/               GPX, FIT, TCX parsers + factory
    sport.py               sport name normalisation
    metrics.py             haversine-based stats computation (single pass)
    timeseries.py          downsample to 1Hz, build BAS timeseries object
    simplify.py            RDP track simplification → GeoJSON
    dedup.py               exact (hash) + near-duplicate detection
    strava_csv.py          Strava activities.csv importer
    writer.py              BAS JSON + GeoJSON writer
    config.py              extract_config.yaml loader
    cli.py                 `bincio extract` CLI
  render/
    cli.py                 `bincio render` CLI (symlinks data, runs astro build/dev)
schema/
  bas-v1.schema.json       JSON Schema for BAS
SCHEMA.md                  Human-readable BAS spec
site/                      Astro project
  src/
    layouts/Base.astro
    pages/
      index.astro           Activity feed (loads index.json client-side)
      activity/[id].astro   Single activity (SSG, loads detail JSON client-side)
      stats/index.astro     Heatmap + year totals
    components/
      ActivityFeed.svelte   Card grid, sport filter, pagination
      ActivityDetail.svelte Map + stats + charts wrapper
      ActivityMap.svelte    MapLibre GL (gradient track, linked hover dot)
      ActivityCharts.svelte Observable Plot (elevation/speed/HR/cadence tabs)
      StatsView.svelte      Yearly heatmap + totals
    lib/
      types.ts              BAS TypeScript types
      format.ts             formatDistance, formatDuration, sportIcon, etc.
```

## How to run

```bash
# Extract
cd ~/src/bincio_activity
uv run bincio extract --input ~/src/cycling_data_davide/activities --output /tmp/bincio_test

# Site dev server
cd site
ln -sf /tmp/bincio_test public/data   # symlink data
BINCIO_DATA_DIR=/tmp/bincio_test npm run dev

# Tests
uv run pytest
```

## MapLibre GL + Vite/Astro — known gotchas

Learnt the hard way during debugging (March 2026):

- **`maplibregl.workerUrl = ...` is the v3 API and silently no-ops in v4+.**
  The v5 API is `maplibregl.setWorkerUrl(url)`, but you don't need it at all in a
  normal Vite environment — MapLibre handles the blob worker automatically.

- **`optimizeDeps: { exclude: ['maplibre-gl'] }` breaks tile loading.**
  It prevents Vite from converting MapLibre's UMD bundle to ESM. The UMD bundle
  uses AMD `define()` internally; served raw, the tile worker blob fails silently →
  black map, no tiles. The correct setting is `include: ['maplibre-gl']`.

- **`build.target: 'es2022'` (and `optimizeDeps.esbuildOptions.target`) is required.**
  MapLibre's dependencies use ES2022 class field syntax. If esbuild downgrades it,
  helpers like `__publicField` aren't available inside the serialised worker blob
  scope → tile loading fails. This is a known upstream issue (maplibre-gl-js #6680).

- **Use static imports, not dynamic `await import('maplibre-gl')`, when possible.**
  With `client:only="svelte"` in Astro, SSR never runs for the component so there is
  no `window is not defined` risk. Static import lets Vite pre-bundle correctly.

- **Use `client:only="svelte"` (not `client:load`) for the activity detail page.**
  `client:load` does SSR + hydration; complex interactive components with MapLibre
  can hit hydration mismatch issues. `client:only` mounts fresh on the client only.

- **MapLibre v5 requires explicit `center` and `zoom` in the Map constructor.**
  v4 silently defaulted to `center: [0,0], zoom: 0`. v5 leaves internal projection
  state undefined → `Cannot read properties of undefined (reading 'lng')` crashes
  on any operation that touches coordinates (markers, resize, render). Always pass
  `center` and `zoom` even if you plan to `fitBounds` later.

- **MapLibre v5 requires `setLngLat()` on markers before `.addTo(map)`.**
  v4 tolerated markers without coordinates. v5 calls `Marker._update()` inside
  `addTo()`, which needs valid lngLat → same `'lng'` crash. Set a dummy `[0, 0]`
  if the real position arrives later (e.g. hover markers).

## Observable Plot — known gotchas

- **Curve names are hyphenated, not camelCase.**
  Use `"monotone-x"`, not `"monotoneX"`. Plot uses its own curve name registry
  (not raw d3 identifiers). Wrong names throw `unknown curve` at runtime.

The working `astro.config.mjs` Vite section:
```js
vite: {
  optimizeDeps: {
    include: ['maplibre-gl'],
    esbuildOptions: { target: 'es2022' },
  },
  build: { target: 'es2022' },
},
```

## Known issues / next steps

- `bincio render` Python CLI is a stub — site is built via `npm run build` directly
- Activity IDs in existing test data still use `+0000` format (pre-fix); re-run extract to get `Z` format
- Some activities appear with both untitled and titled IDs (near-dedup timing race)
- Stats page heatmap month labels use absolute positioning and may misalign
- Federation (remote data sources) not yet implemented in site
- Friends pages (`/friends/{handle}/`) not yet implemented
- `bincio render` should automate: symlink data → `astro build`
- The `site/.env` file is gitignored — document the setup for new users
- Add `--workers` benchmark: on 8 cores, ~7 min for 3,200 activities first run

## What "good" looks like (not yet done)

- [ ] `bincio render` Python CLI wraps `astro build` properly
- [ ] Friends/federation pages in site
- [ ] Personal records page
- [ ] Activity search / full-text filter in feed
- [ ] Map thumbnail in activity cards (SVG path from GeoJSON)
- [ ] GitHub Actions template for auto-publish
- [ ] Karoo/Garmin Connect importers beyond Strava