name: CI

on:
  push:
    branches: [main]
  pull_request:

# A second push to the same branch makes the first run's result irrelevant.
concurrency:
  group: ci-${{ github.ref }}
  cancel-in-progress: true

permissions:
  contents: read

jobs:
  go:
    name: Go
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-go@v5
        with:
          go-version: "1.26"
          cache: true

      - name: Formatting
        run: |
          unformatted=$(gofmt -l .)
          if [ -n "$unformatted" ]; then
            echo "These files are not gofmt'd:"
            echo "$unformatted"
            exit 1
          fi

      - name: Vet
        run: go vet ./...

      # -race is the whole point of running tests in CI for a server with a
      # WebSocket fan-out: a data race is exactly the bug that passes locally.
      - name: Test
        # -timeout, fordi internal/httpapi nærmer sig Go's standardgrænse på 600s:
        # 498s i CI på #95, 656s på udviklingsmaskinen. Når den krydser, er
        # beskeden "panic: test timed out after 10m0s" plus et goroutine-dump, og
        # det læser som en deadlock i koden frem for som en suite, der blev for
        # stor. Grænsen er der stadig; den er bare sat et sted, hvor den betyder
        # "noget hænger" i stedet for "maskinen var langsom i dag".
        run: go test -race -count=1 -timeout 20m ./...

      - name: Build
        run: CGO_ENABLED=0 go build ./...

  spec:
    name: OpenAPI is valid
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: "22"

      # Structural validity only. That the spec matches the *router* is checked by
      # a Go test, which is the half that actually goes stale.
      - run: npx --yes @redocly/cli@latest lint docs/openapi.yaml

  e2e:
    name: End-to-end
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-go@v5
        with:
          go-version: "1.26"
          cache: true

      - uses: actions/setup-node@v4
        with:
          node-version: "22"
          cache: npm
          cache-dependency-path: web/package-lock.json

      - name: Install
        working-directory: web
        run: npm ci --no-audit --no-fund

      # Chromium for the suite, WebKit for one test.
      #
      # A smoke test exists to catch a build that does not work at all, and running
      # the whole thing in three engines finds the same breakage three times for
      # three times the cost. Focus is the exception, and it took a real report to
      # learn it: Safari ignores `autofocus` on anything inserted after the page has
      # loaded, so every inline form in the app opened with no cursor in it. WebKit
      # here is the same engine Safari is, and `webkit-forms` in the Playwright
      # config greps a single test out of the suite to run in it.
      - name: Install browsers
        working-directory: web
        run: npx playwright install --with-deps chromium webkit

      # The suite builds the frontend, embeds it and starts the real binary — see
      # playwright.config.js. There is nothing to build here first.
      - name: Test
        working-directory: web
        run: npm run test:e2e

      - if: failure()
        uses: actions/upload-artifact@v4
        with:
          name: playwright-report
          path: |
            web/test-results/
            web/playwright-report/
          retention-days: 7

  docker:
    name: Docker image builds
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: docker/setup-buildx-action@v3

      # Build only — publishing happens on a tag, in release.yml. This job exists
      # so a Dockerfile that no longer builds fails on the pull request rather
      # than at release time.
      #
      # Loaded into the local daemon rather than discarded, because the step below
      # has to inspect what came out.
      - uses: docker/build-push-action@v6
        with:
          context: .
          push: false
          load: true
          tags: verdande:ci
          cache-from: type=gha
          cache-to: type=gha,mode=max

      - uses: docker/build-push-action@v6
        with:
          context: .
          push: false
          load: true
          tags: urd:ci
          build-args: EDITION=notes
          cache-from: type=gha
          cache-to: type=gha,mode=max

      # The claim this repository makes about urd is that it is the same program,
      # not a fork — and that claim is checkable rather than a sentence in a README.
      #
      # Stages 1 and 2 are identical for both builds, and the edition is set with
      # ENV, which is image *config* rather than a layer. So the two images must
      # have the same layer digests and differ only in that one variable. A change
      # that made them diverge — a second COPY, a conditional RUN, a separate build
      # of the binary — would quietly turn "one source" into two, and the only
      # symptom would be a bug fixed in one product and not the other.
      #
      # This was impossible until the frontend build became deterministic: SvelteKit
      # put Date.now() in version.json, so no two builds ever matched. See the note
      # in web/svelte.config.js.
      - name: The two images are one build
        run: |
          set -eu
          layers() { docker image inspect "$1" --format '{{json .RootFS.Layers}}'; }
          if [ "$(layers verdande:ci)" != "$(layers urd:ci)" ]; then
            echo "The verdande and urd images do not share their layers:"
            layers verdande:ci
            layers urd:ci
            echo "They are built from one source, so this is either a Dockerfile that"
            echo "now builds the binary twice, or a stage that is no longer shared."
            exit 1
          fi
          echo "Shared layers: $(layers verdande:ci | tr ',' '\n' | wc -l)"

          # And the half that stops the check above from passing over two identical
          # images: they must actually differ in the one way they are supposed to.
          edition() { docker image inspect "$1" --format '{{json .Config.Env}}' | tr ',' '\n' | grep VERDANDE_EDITION; }
          echo "verdande: $(edition verdande:ci)"
          echo "urd:      $(edition urd:ci)"
          edition verdande:ci | grep -q 'VERDANDE_EDITION=full'
          edition urd:ci | grep -q 'VERDANDE_EDITION=notes'