name: Report API Diff

on:
  workflow_run:
    types: [completed]
    workflows:
      - Get api.json from Misskey # get-api-diff.yml

jobs:
  compare-diff:
    runs-on: ubuntu-latest
    if: ${{ github.event.workflow_run.conclusion == 'success' }}
    permissions:
      actions: read
      pull-requests: write

# api-artifact
    steps:
      - name: Download artifacts
        uses: actions/download-artifact@v8
        with:
          pattern: api-artifact-*
          path: artifacts
          merge-multiple: true
          github-token: ${{ github.token }}
          repository: ${{ github.repository }}
          run-id: ${{ github.event.workflow_run.id }}
      - name: Check artifacts
        run: ls -lh artifacts/
      - name: Load PR Number
        id: load-pr-num
        run: echo "pr-number=$(cat artifacts/pr_number)" >> "$GITHUB_OUTPUT"

      - name: Arrange json files
        run: |
          jq '.' ./artifacts/api-base.json > ./api-base.json
          jq '.' ./artifacts/api-head.json > ./api-head.json
      - name: Get diff of 2 files
        run: diff -u --label=base --label=head ./api-base.json ./api-head.json | cat > api.json.diff
      - name: Get full diff
        run: diff --label=base --label=head --new-line-format='+%L' --old-line-format='-%L' --unchanged-line-format=' %L' ./api-base.json ./api-head.json | cat > api-full.json.diff
      - name: Upload full diff to Artifact
        uses: actions/upload-artifact@v7
        with:
          name: api-artifact
          path: |
            api-full.json.diff
            api-base.json
            api-head.json
      - id: out-diff
        name: Build diff Comment
        run: |
          HEADER="このPRによるapi.jsonの差分"
          FOOTER="[Get diff files from Workflow Page](https://github.com/${GITHUB_REPOSITORY}/actions/runs/${GITHUB_RUN_ID})"
          DIFF_BYTES="$(stat ./api.json.diff -c '%s' | tr -d '\n')"

          echo "$HEADER" > ./output.md

          if (( "$DIFF_BYTES" <= 1 )); then
            echo '差分はありません。' >> ./output.md
          else
            echo '<details>' >> ./output.md
            echo '<summary>差分はこちら</summary>' >> ./output.md
            echo >> ./output.md
            echo '```diff' >> ./output.md
            cat ./api.json.diff >> ./output.md
            echo '```' >> ./output.md
            echo '</details>' >> ./output.md
          fi

          echo "$FOOTER" >> ./output.md
      - uses: thollander/actions-comment-pull-request@v3
        with:
          pr-number: ${{ steps.load-pr-num.outputs.pr-number }}
          comment-tag: show_diff
          file-path: ./output.md
      - name: Tell error to PR
        uses: thollander/actions-comment-pull-request@v3
        if: failure() && steps.load-pr-num.outputs.pr-number
        with:
          pr-number: ${{ steps.load-pr-num.outputs.pr-number }}
          comment-tag: show_diff_error
          message: |
            api.jsonの差分作成中にエラーが発生しました。詳細は[Workflowのログ](https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }})を確認してください。