name: update runner reference

on:
  schedule:
    - cron: '30 3 * * 1' # every Monday at 03:30
  workflow_dispatch:

env:
  # main is protected, so the update is proposed as a pull request from this branch
  BOT_BRANCH: bot/update-runner-reference
  BASE_BRANCH: main
  # the develop runner docs follow the main branch of gitea/runner, every
  # documented release series follows its newest stable tag. The value is used
  # unquoted, so the glob is expanded by the shell of each step.
  TARGET_DIRS: runner-docs/reference runner-docs_versioned_docs/version-*/reference

jobs:
  update-runner-reference:
    if: github.repository == 'gitea/docs'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7
        with:
          ref: main
          # pushing uses DEPLOY_TOKEN, keep the ephemeral job token out of .git/config
          persist-credentials: false
      - uses: actions/setup-go@b7ad1dad31e06c5925ef5d2fc7ad053ef454303e # v7
        with:
          go-version: 'stable'
          cache: false
      - name: regenerate the runner reference pages
        run: |
          set -euo pipefail
          ./update_runner_docs.sh main runner-docs/reference
          ./update_runner_docs.sh --released
      - name: verify the generated files
        run: |
          set -euo pipefail
          # the pages are built from `--help` and `generate-config`, so a truncated
          # build would silently produce an almost empty page
          for dir in $TARGET_DIRS; do
            echo "checking $dir"
            grep -q 'gitea-runner \[command\]' "$dir/cli.md"
            grep -q 'gitea-runner exec \[flags\]' "$dir/cli.md"
            grep -q '^runner:' "$dir/config-example.md"
          done
      - name: push bot branch
        id: bot_branch
        env:
          DEPLOY_TOKEN: ${{ secrets.DEPLOY_TOKEN }}
        run: |
          set -euo pipefail

          if git diff --quiet -- $TARGET_DIRS; then
            echo "the runner reference is already up to date"
            echo "changed=false" >> "$GITHUB_OUTPUT"
            exit 0
          fi

          if [ -z "$DEPLOY_TOKEN" ]; then
            echo "secrets.DEPLOY_TOKEN is missing, cannot push the update"
            exit 1
          fi
          remote="https://x-access-token:$DEPLOY_TOKEN@${GITHUB_SERVER_URL#*://}/$GITHUB_REPOSITORY.git"

          # skip if an open bot branch already carries exactly these files
          if git fetch --quiet --depth=1 "$remote" "refs/heads/$BOT_BRANCH" 2>/dev/null; then
            if git diff --quiet FETCH_HEAD -- $TARGET_DIRS; then
              echo "$BOT_BRANCH already proposes this runner reference"
              echo "changed=false" >> "$GITHUB_OUTPUT"
              exit 0
            fi
          fi

          git config user.name "Gitea Bot"
          git config user.email "teabot@gitea.io"
          git switch --create "$BOT_BRANCH"
          git add $TARGET_DIRS
          git commit -m "Update the runner reference pages"
          # force push: the branch is always rebuilt on top of the current main
          git push --force "$remote" "HEAD:refs/heads/$BOT_BRANCH"
          echo "changed=true" >> "$GITHUB_OUTPUT"
      - name: create pull request
        if: steps.bot_branch.outputs.changed == 'true'
        env:
          DEPLOY_TOKEN: ${{ secrets.DEPLOY_TOKEN }}
        run: |
          set -euo pipefail

          cat > pull.json <<EOF
          {
            "base": "$BASE_BRANCH",
            "head": "$BOT_BRANCH",
            "title": "Update the runner reference pages",
            "body": "Automated update of the generated runner reference pages from gitea/runner (main for the develop docs, the newest stable tag for every documented series), opened by the \"update runner reference\" scheduled workflow."
          }
          EOF

          code="$(curl --silent --show-error --output pull-response.json --write-out '%{http_code}' \
            -X POST "${GITHUB_API_URL:-$GITHUB_SERVER_URL/api/v1}/repos/$GITHUB_REPOSITORY/pulls" \
            -H "Authorization: token $DEPLOY_TOKEN" \
            -H 'Content-Type: application/json' \
            --data @pull.json)"

          case "$code" in
            201) echo "pull request created" ;;
            409) echo "an open pull request for $BOT_BRANCH already exists, it now points at the new commit" ;;
            *) echo "unexpected response $code:"; cat pull-response.json; exit 1 ;;
          esac