name: Deploy to GitHub Pages

on:
  push:
    branches: [main]
  # Pull requests run the build job only: the deploy job is guarded to main, so
  # a branch can be verified end to end without touching the live site.
  pull_request:
  workflow_dispatch:

permissions:
  contents: read
  pages: write
  id-token: write

concurrency:
  group: pages
  cancel-in-progress: true

jobs:
  build:
    runs-on: ubuntu-latest
    env:
      # Every Go module here is cgo-free — grate, excelize, yaml.v3, x/net,
      # x/text and modernc.org/sqlite — so no C toolchain is needed. Set
      # explicitly rather than relying on the default.
      CGO_ENABLED: '0'
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-go@v5
        with:
          go-version: '1.26'
          cache-dependency-path: |
            parser/go.sum
            crawler/go.sum
            assembler/go.sum

      # web/ is the only npm project in the repository; the other stages are Go.
      - uses: actions/setup-node@v4
        with:
          node-version: '24'
          cache: 'npm'
          cache-dependency-path: web/package-lock.json

      - name: Install web dependencies
        working-directory: web
        run: npm ci

      # The reader-fidelity suite compares every real input file against a
      # committed hash oracle, so it is the regression guard for the whole
      # reader. Runs before anything is built.
      - name: Test parser
        run: go -C parser test ./...

      # The crawler is not part of the build — it only refreshes data/ by hand.
      # It is still tested here so it cannot rot unnoticed, and because its
      # fixture test guards the parser: input filenames decide which row
      # survives a duplicate exam number.
      - name: Test crawler
        run: go -C crawler test ./...

      # The assembler owns every guard between a built database and the
      # published site, so its tests are the ones that prove a short or missing
      # database cannot ship.
      - name: Test assembler
        run: go -C assembler test ./...

      # The tests cover the framework-free modules, including the ASCII fold
      # that has to match the Go parser.
      - name: Test web
        working-directory: web
        run: npm test

      - name: Lint web
        working-directory: web
        run: npm run lint

      # excelize carries an open advisory, and the 2017 refresh runbook feeds
      # network-downloaded spreadsheets straight into the parser.
      - name: Vulnerability scan
        run: |
          go install golang.org/x/vuln/cmd/govulncheck@latest
          GOVULNCHECK="$(go env GOPATH)/bin/govulncheck"
          for m in parser crawler assembler; do (cd "$m" && "$GOVULNCHECK" ./...); done

      # One command runs the whole pipeline: compile the parser, build and
      # verify each database against its registry row count, compress it, build
      # the web app, and assemble _site — refusing to continue if a database is
      # short, an artifact looks truncated, or one is missing entirely.
      - name: Build site
        run: go -C assembler run ./cmd/assemble

      - uses: actions/upload-pages-artifact@v3
        with:
          path: _site

  deploy:
    # Deploy only from main. pull_request and workflow_dispatch both run on
    # other branches, and publishing one would put that branch's output on the
    # live site while concurrency cancel-in-progress killed an in-flight good
    # deploy on the way.
    if: github.ref == 'refs/heads/main'
    needs: build
    runs-on: ubuntu-latest
    environment:
      name: github-pages
      url: ${{ steps.deployment.outputs.page_url }}
    steps:
      - id: deployment
        uses: actions/deploy-pages@v4