# Lighthouse protocol for Flutter web

Detta dokument implementerar en reproducerbar baseline/eftermatning enligt planen i `.kilo/plans/1779550355555-hidden-mountain.md`.

## 1) Fast matprofil (anvand samma varje gang)

- URL: samma exakta URL per miljo (`http://localhost:5000` respektive produktion).
- Form factor: `mobile`.
- Lighthouse-kategorier: `performance`, `accessibility`, `seo`.
- Antal korningar: minst 3 per miljo.
- Throttling: `simulate` (Lighthouse standard, konstant mellan korningar).

## 2) Korningar

Lokal container:

```bash
docker compose -f compose.yml -f compose.flutter.yml up -d --build recipe-api recipe-flutter
node flutter/lighthouse/collect.mjs --url http://localhost:5000 --label local-baseline --runs 3 --form-factor mobile
```

Produktion:

```bash
node flutter/lighthouse/collect.mjs --url https://DIN-DOMAN --label prod-baseline --runs 3 --form-factor mobile
```

Resultat skrivs till `flutter/lighthouse/results/` som:

- `<label>-run-1.json`, `<label>-run-2.json`, `<label>-run-3.json`
- `<label>-summary.json`
- `<label>-summary.md`

## 3) Baseline-tabell (fylls med faktiska resultat)

| Miljo | Perf median | A11y median | SEO median | LCP ms median | TBT ms median | INP ms median | Transfer KB median | Requests median |
| --- | ---: | ---: | ---: | ---: | ---: | ---: | ---: | ---: |
| Lokal container | TODO | TODO | TODO | TODO | TODO | TODO | TODO | TODO |
| Produktion | TODO | TODO | TODO | TODO | TODO | TODO | TODO | TODO |

## 4) Re-matning efter andringar

Kor samma kommandon med nya labels, till exempel:

```bash
node flutter/lighthouse/collect.mjs --url http://localhost:5000 --label local-after --runs 3 --form-factor mobile
node flutter/lighthouse/collect.mjs --url https://DIN-DOMAN --label prod-after --runs 3 --form-factor mobile
```

Jamor `*-summary.md` mot baseline for att verifiera:

- Forbattring i minst tva nyckelmatt (exempel LCP/TBT)
- Ingen regress i Accessibility/SEO

## 5) Renderer A/B (Fas 3)

`flutter/Dockerfile` och `compose.flutter.yml` har nu build-args for rendererexperiment:

- `WEB_RENDERER=auto` (default)
- `WEB_RENDERER=canvaskit`
- `WEB_RENDERER=skwasm`

Exempel (separat buildvariant):

```bash
docker compose -f compose.yml -f compose.flutter.yml build --build-arg WEB_RENDERER=canvaskit recipe-flutter
docker compose -f compose.yml -f compose.flutter.yml up -d recipe-flutter
node flutter/lighthouse/collect.mjs --url http://localhost:5000 --label local-canvaskit --runs 3 --form-factor mobile
```

Rollback-kriterium: behall `WEB_RENDERER=auto` om A/B inte ger tydlig forbattring i transfer size + LCP/TBT utan visuell regress.

## 6) SEO routing-beslut

- `robots.txt` hanteras i Flutter web app-shell (`flutter/web/robots.txt`).
- `sitemap.xml` hanteras upstream pa domanniva eftersom absolut canonical host maste vara korrekt per miljo.