name: Build & publish

on:
  push:
    tags:
      - "draft*"
      - "rc*"
      - "v*"
  workflow_dispatch:
    inputs:
      release_tag:
        description: "Existing tag to publish, for example draft2026, rc2026, or v2026"
        required: true
        type: string

permissions:
  contents: write

env:
  MKDOCS_CONFIG: mkdocs/mkdocs.yml
  MKDOCS_STRICT: ${{ vars.MKDOCS_STRICT || 'true' }}
  RELEASE_TAG: ${{ inputs.release_tag || github.ref_name }}

jobs:
  publish:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout (tag)
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          ref: ${{ inputs.release_tag || github.ref }}

      - name: Validate release tag
        run: |
          set -euo pipefail

          case "${RELEASE_TAG}" in
            draft*|rc*|v*) ;;
            *)
              echo "::error::Release tag must start with draft, rc, or v. Got '${RELEASE_TAG}'."
              exit 1
              ;;
          esac

          if ! git rev-parse --verify --quiet "refs/tags/${RELEASE_TAG}" >/dev/null; then
            echo "::error::Tag '${RELEASE_TAG}' was not found. Create and push the tag before running this workflow."
            exit 1
          fi

          echo "RELEASE_COMMIT=$(git rev-list -n 1 "${RELEASE_TAG}")" >> "${GITHUB_ENV}"

      - name: Setup Python
        uses: actions/setup-python@v5
        with:
          python-version: "3.11"

      - name: Install deps
        run: |
          set -euo pipefail
          pip install -r mkdocs/requirements.txt

          if ! command -v pandoc >/dev/null 2>&1; then
            sudo apt-get update
            sudo apt-get install -y pandoc
          fi

      - name: Build docs (normal + offline, strict gate)
        run: |
          set -euo pipefail

          REPO_SLUG="${GITHUB_REPOSITORY#*/}"
          BASE_SITE_URL="https://${GITHUB_REPOSITORY_OWNER}.github.io/${REPO_SLUG}/"
          MKDOCS_REPO_URL="https://github.com/${GITHUB_REPOSITORY}/tree/${RELEASE_TAG}"
          MKDOCS_REPO_NAME="${GITHUB_REPOSITORY}"

          if [[ "${RELEASE_TAG}" == draft* ]]; then
            MKDOCS_SITE_URL="${BASE_SITE_URL}draft/"
          elif [[ "${RELEASE_TAG}" == rc* ]]; then
            MKDOCS_SITE_URL="${BASE_SITE_URL}rc/"
          else
            MKDOCS_SITE_URL="${BASE_SITE_URL}"
          fi

          export MKDOCS_SITE_URL MKDOCS_REPO_URL MKDOCS_REPO_NAME

          FLAGS=()
          if [ "${MKDOCS_STRICT}" = "true" ]; then
            FLAGS+=(--strict)
          fi

          OUT_BASE="${RUNNER_TEMP}/mkdocs_out"
          SITE="${OUT_BASE}/site"
          SITE_OFFLINE="${OUT_BASE}/site_offline/${RELEASE_TAG}"

          rm -rf "${OUT_BASE}"
          mkdir -p "${SITE}" "${SITE_OFFLINE}"

          mkdocs build "${FLAGS[@]}" -f "${MKDOCS_CONFIG}" -d "${SITE}"
          OFFLINE=true mkdocs build "${FLAGS[@]}" -f "${MKDOCS_CONFIG}" -d "${SITE_OFFLINE}"
      
      - name: Export docx
        run: |
          set -euo pipefail

          SHORT_SHA="${GITHUB_SHA::7}"

          OUT_DIR="${RUNNER_TEMP}/pandoc"
          OUT_FILE="${RELEASE_TAG}-${SHORT_SHA}.docx"
          echo "SHORT_SHA=`echo ${SHORT_SHA}`" >> $GITHUB_ENV

          mkdir -p "${OUT_DIR}"

          # Collect markdown files, excluding README.md and docs/index.md
          mapfile -t MD_FILES < <(
            find docs -name '*.md' \
              ! -name 'index.md' \
              ! -name 'README.md' \
              | sort
          )

          echo "Generating ${OUT_FILE}"

          # Adjust input paths as needed
          pandoc \
            "${MD_FILES[@]}" \
            --number-sections  \
            -o "${OUT_DIR}/${OUT_FILE}"
          
          echo "Pandoc output written to ${OUT_DIR}/${OUT_FILE}"

      - name: Zip offline site
        run: |
          set -euo pipefail
          cd "${RUNNER_TEMP}/mkdocs_out/site_offline/"
          zip -r "${RELEASE_TAG}.zip" ./${RELEASE_TAG}

      - name: Prepare release notes
        run: |
          set -euo pipefail

          RELEASE_NOTES="${RUNNER_TEMP}/release-notes.md"

          if [[ "${RELEASE_TAG}" == draft* || "${RELEASE_TAG}" == rc* ]]; then
            printf 'Prerelease.\n\n' > "${RELEASE_NOTES}"
          else
            : > "${RELEASE_NOTES}"
          fi

          cat docs/summary-of-changes.md >> "${RELEASE_NOTES}"

      - name: Publish prerelease
        if: startsWith(env.RELEASE_TAG, 'rc') || startsWith(env.RELEASE_TAG, 'draft')
        uses: ncipollo/release-action@v1
        with:
          allowUpdates: true
          artifacts: ${{ runner.temp }}/mkdocs_out/site_offline/${{ env.RELEASE_TAG }}.zip,${{ runner.temp }}/pandoc/${{ env.RELEASE_TAG }}-${{ env.SHORT_SHA }}.docx
          bodyFile: ${{ runner.temp }}/release-notes.md
          commit: ${{ env.RELEASE_COMMIT }}
          name: ${{ env.RELEASE_TAG }}
          prerelease: true
          replacesArtifacts: true
          tag: ${{ env.RELEASE_TAG }}
          token: ${{ secrets.GITHUB_TOKEN }}

      - name: Publish release
        if: startsWith(env.RELEASE_TAG, 'v')
        uses: ncipollo/release-action@v1
        with:
          allowUpdates: true
          artifacts: ${{ runner.temp }}/mkdocs_out/site_offline/${{ env.RELEASE_TAG }}.zip,${{ runner.temp }}/pandoc/${{ env.RELEASE_TAG }}-${{ env.SHORT_SHA }}.docx
          bodyFile: ${{ runner.temp }}/release-notes.md
          commit: ${{ env.RELEASE_COMMIT }}
          name: ${{ env.RELEASE_TAG }}
          replacesArtifacts: true
          tag: ${{ env.RELEASE_TAG }}
          token: ${{ secrets.GITHUB_TOKEN }}

      - name: Checkout gh-pages branch
        uses: actions/checkout@v4
        with:
          ref: gh-pages
          fetch-depth: 0

      - name: Deploy release to gh-pages root
        if: startsWith(env.RELEASE_TAG, 'v')
        run: |
          set -euo pipefail
          rm -rf ./*
          cp -a ${RUNNER_TEMP}/mkdocs_out/site/. .
          git add -A
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
          git commit -m "Deploy release ${RELEASE_TAG}" || echo "No changes to commit"
          git push origin gh-pages

      - name: Deploy RC preview to /rc/
        if: startsWith(env.RELEASE_TAG, 'rc')
        run: |
          set -euo pipefail
          rm -rf rc draft
          mkdir -p rc
          cp -a ${RUNNER_TEMP}/mkdocs_out/site/. rc/
          printf '{"tag":"%s"}\n' "${RELEASE_TAG}" > rc/rc.json

          git add -A
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
          git commit -m "Deploy RC preview ${RELEASE_TAG}" || echo "No changes to commit"
          git push origin gh-pages
      
      - name: Deploy draft preview to /draft/
        if: startsWith(env.RELEASE_TAG, 'draft')
        run: |
          set -euo pipefail
          rm -rf rc draft
          mkdir -p draft
          cp -a ${RUNNER_TEMP}/mkdocs_out/site/. draft/
          printf '{"tag":"%s"}\n' "${RELEASE_TAG}" > draft/draft.json

          git add -A
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
          git commit -m "Deploy draft preview ${RELEASE_TAG}" || echo "No changes to commit"
          git push origin gh-pages