name: Upgrade one Python dependency

on:
  workflow_dispatch:
    inputs:
      branch:
        description: "Target branch to create requirements PR against"
        required: true
        default: "master"
        type: string
      package:
        description: "Name of package to upgrade"
        required: true
        type: string
      version:
        description: "Version number to upgrade to in constraints.txt (only needed if pinned)"
        default: ""
        type: string
      change_desc:
        description: |
          Description of change, for commit message and PR. (What does the new version add or fix?)
        default: ""
        type: string

defaults:
  run:
    shell: bash # making this explicit opts into -e -o pipefail

jobs:
  upgrade-one-python-dependency:
    runs-on: ubuntu-20.04

    steps:
      - name: Check out target branch
        uses: actions/checkout@v4
        with:
          ref: "${{ inputs.branch }}"

      - name: Set up Python environment
        uses: actions/setup-python@v5
        with:
          python-version: "3.11"

      - name: Update any pinned dependencies
        env:
          NEW_VERSION: "${{ inputs.version }}"
          PACKAGE: "${{ inputs.package }}"
        run: |
          sed 's/^\('$PACKAGE'[^#]*\)==[^ #]\+/\1=='$NEW_VERSION'/' -i requirements/constraints.txt

      - name: Run make upgrade-package
        env:
          PACKAGE: "${{ inputs.package }}"
        run: |
          make upgrade-package package="$PACKAGE"

      - name: PR preflight
        env:
          CHANGE_DESC: "${{ inputs.change_desc }}"
        run: |
          if git diff --exit-code; then
              # Fail early (and avoid quiet failure of create-pull-request action)
              echo "Error: No changes, so not creating PR." | tee -a "$GITHUB_STEP_SUMMARY"
              exit 1
          else
              # There are changes to commit, so prep some info for the PR.

              # This is honestly a lot to go through just to say "add two newlines
              # on the end if the variable isn't empty" but I guess this is what we
              # have to do to get a conditional delimiter.
              if [[ -z "$CHANGE_DESC" ]]; then
                  echo "body_prefix=" >> "$GITHUB_ENV"
              else
                  EOF=$(dd if=/dev/urandom bs=15 count=1 status=none | base64)
                  echo "body_prefix<<$EOF" >> "$GITHUB_ENV"
                  echo "$CHANGE_DESC" >> "$GITHUB_ENV"
                  echo "" >> "$GITHUB_ENV"
                  echo "" >> "$GITHUB_ENV"
                  echo "$EOF" >> "$GITHUB_ENV"
              fi
          fi

      - name: Make a PR
        id: make-pr
        uses: peter-evans/create-pull-request@v6
        with:
          branch: "${{ github.triggering_actor }}/upgrade-${{ inputs.package }}"
          branch-suffix: short-commit-hash
          add-paths: |
            requirements
            scripts/**/requirements*
          commit-message: |
            feat: Upgrade Python dependency ${{ inputs.package }}

            ${{ env.body_prefix }}Commit generated by workflow `${{ github.workflow_ref }}`
          title: "feat: Upgrade Python dependency ${{ inputs.package }}"
          body: >-
            ${{ env.body_prefix }}PR generated by workflow `${{ github.workflow_ref }}`
            on behalf of @${{ github.triggering_actor }}.
          assignees: "${{ github.triggering_actor }}"
          reviewers: "${{ github.triggering_actor }}"

      - name: Job summary
        env:
          PR_URL: "${{ steps.make-pr.outputs.pull-request-url }}"
        run: |
          if [[ -z "$PR_URL" ]]; then
              echo "PR not created; see log for more information" | tee -a "$GITHUB_STEP_SUMMARY"
              exit 1
          else
              echo "PR created or updated: $PR_URL" | tee -a "$GITHUB_STEP_SUMMARY"
          fi