name: Auto-merge Dependabot PRs

on:
  workflow_run:
    workflows: [ "Pull Request" ]
    types: [ completed ]

jobs:
  merge-dependabot:
    if: "github.actor == 'dependabot[bot]'
      && github.event.workflow_run.event == 'pull_request'
      && github.event.workflow_run.conclusion == 'success'"
    runs-on: ubuntu-latest
    steps:
      # Note: this is directly from GitHub's example for using data from a triggering workflow:
      # https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#using-data-from-the-triggering-workflow
      - name: 'Download artifact'
        uses: actions/github-script@v6
        with:
          script: |
            let allArtifacts = await github.rest.actions.listWorkflowRunArtifacts({
               owner: context.repo.owner,
               repo: context.repo.repo,
               run_id: context.payload.workflow_run.id,
            });
            let matchArtifact = allArtifacts.data.artifacts.filter((artifact) => {
              return artifact.name == "pr_number"
            })[0];
            let download = await github.rest.actions.downloadArtifact({
               owner: context.repo.owner,
               repo: context.repo.repo,
               artifact_id: matchArtifact.id,
               archive_format: 'zip',
            });
            let fs = require('fs');
            fs.writeFileSync(`${process.env.GITHUB_WORKSPACE}/pr_number.zip`, Buffer.from(download.data));

      # This might be a useless use of cat, but I'm not sure what shell Actions is going to be running.
      - name: Add Pull Number Variable
        run: |-
          unzip pr_number.zip
          echo "PR_NUMBER=$(cat pr_number)" >> "$GITHUB_ENV"

      - name: Approve
        uses: hmarr/auto-approve-action@v3.2.1
        with:
          github-token: "${{ secrets.GITHUB_TOKEN }}"
          pull-request-number: "${{ env.PR_NUMBER }}"
      - name: Merge
        uses: pascalgn/automerge-action@v0.15.6
        env:
          GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"
          MERGE_LABELS: "dependencies,java"
          MERGE_METHOD: "squash"
          PULL_REQUEST: "${{ env.PR_NUMBER }}"