name: update api spec files

on:
  schedule:
    - cron:  '0 */12 * * *' # every 12 hours on the hour
  workflow_dispatch:

env:
  # main is protected, so the update is proposed as a pull request from this branch
  BOT_BRANCH: bot/update-swagger-latest
  BASE_BRANCH: main
  # the documents of the gitea main branch, refreshed by this job
  LATEST_FILES: static/swagger-latest.json static/openapi3-latest.json

jobs:
  update-swagger:
    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
      - name: regenerate the latest api documents
        run: make update-api-docs-latest
      - name: verify the generated file
        run: |
          set -euo pipefail
          for file in $LATEST_FILES; do
            # placeholders must have been replaced, otherwise upstream changed them again
            if grep -q -e 'GITEA-API-APP' -e '{{' "$file"; then
              echo "$file still contains template placeholders"
              exit 1
            fi
            if command -v python3 >/dev/null 2>&1; then
              python3 -c "import json,sys; json.load(open(sys.argv[1]))" "$file"
            fi
          done
      - name: push bot branch
        id: bot_branch
        env:
          DEPLOY_TOKEN: ${{ secrets.DEPLOY_TOKEN }}
        run: |
          set -euo pipefail

          if git diff --quiet -- $LATEST_FILES; then
            echo "the api documents are already up to date"
            echo "changed=false" >> "$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 this file
          if git fetch --quiet --depth=1 "$remote" "refs/heads/$BOT_BRANCH" 2>/dev/null; then
            same=true
            for file in $LATEST_FILES; do
              old_blob="$(git rev-parse --quiet --verify "FETCH_HEAD:$file" || true)"
              if [ "$old_blob" != "$(git hash-object "$file")" ]; then
                same=false
                break
              fi
            done
            if [ "$same" = true ]; then
              echo "$BOT_BRANCH already proposes these api documents"
              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 $LATEST_FILES
          git commit -m "Update the latest api documents"
          # force push: the branch is always rebuilt on top of the current main
          git push --force "$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 latest api documents",
            "body": "Automated update of static/swagger-latest.json and static/openapi3-latest.json from the gitea main branch, opened by the \"update api spec files\" 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