name: diff-shades

on:
  push:
    branches: [main]
    paths-ignore: ["docs/**", "tests/**", "*.md"]

  pull_request:
    path-ignore: ["docs/**", "tests/**", "*.md"]

  workflow_dispatch:
    inputs:
      baseline:
        description: >
          The baseline revision. Pro-tip, use `.pypi` to use the latest version
          on PyPI or `.XXX` to use a PR.
        required: true
        default: main
      baseline-args:
        description: "Custom Black arguments (eg. -l 79)"
        required: false
      target:
        description: >
          The target revision to compare against the baseline. Same tip applies here.
        required: true
      target-args:
        description: "Custom Black arguments (eg. -S)"
        required: false

jobs:
  analysis:
    name: analysis / linux
    runs-on: ubuntu-latest

    steps:
      - name: Checkout this repository (full clone)
        uses: actions/checkout@v2
        with:
          fetch-depth: 0

      - uses: actions/setup-python@v2

      - name: Install diff-shades and support dependencies
        run: |
          python -m pip install pip --upgrade
          python -m pip install https://github.com/ichard26/diff-shades/archive/stable.zip
          python -m pip install click packaging urllib3
          # After checking out old revisions, this might not exist so we'll use a copy.
          cat scripts/diff_shades_gha_helper.py > helper.py
          git config user.name "diff-shades-gha"
          git config user.email "diff-shades-gha@example.com"

      - name: Calculate run configuration & metadata
        id: config
        env:
          GITHUB_TOKEN: ${{ github.token }}
        run: >
          python helper.py config ${{ github.event_name }}
          ${{ github.event.inputs.baseline }} ${{ github.event.inputs.target }}
          --baseline-args "${{ github.event.inputs.baseline-args }}"

      - name: Attempt to use cached baseline analysis
        id: baseline-cache
        uses: actions/cache@v2.1.7
        with:
          path: ${{ steps.config.outputs.baseline-analysis }}
          key: ${{ steps.config.outputs.baseline-cache-key }}

      - name: Install baseline revision
        if: steps.baseline-cache.outputs.cache-hit != 'true'
        env:
          GITHUB_TOKEN: ${{ github.token }}
        run: ${{ steps.config.outputs.baseline-setup-cmd }} && python -m pip install .

      - name: Analyze baseline revision
        if: steps.baseline-cache.outputs.cache-hit != 'true'
        run: >
          diff-shades analyze -v --work-dir projects-cache/
          ${{ steps.config.outputs.baseline-analysis }} -- ${{ github.event.inputs.baseline-args }}

      - name: Install target revision
        env:
          GITHUB_TOKEN: ${{ github.token }}
        run: ${{ steps.config.outputs.target-setup-cmd }} && python -m pip install .

      - name: Analyze target revision
        run: >
          diff-shades analyze -v --work-dir projects-cache/
          ${{ steps.config.outputs.target-analysis }} --repeat-projects-from
          ${{ steps.config.outputs.baseline-analysis }} -- ${{ github.event.inputs.target-args }}

      - name: Generate HTML diff report
        run: >
          diff-shades --dump-html diff.html compare --diff --quiet
          ${{ steps.config.outputs.baseline-analysis }} ${{ steps.config.outputs.target-analysis }}

      - name: Upload diff report
        uses: actions/upload-artifact@v2
        with:
          name: diff.html
          path: diff.html

      - name: Upload baseline analysis
        uses: actions/upload-artifact@v2
        with:
          name: ${{ steps.config.outputs.baseline-analysis }}
          path: ${{ steps.config.outputs.baseline-analysis }}

      - name: Upload target analysis
        uses: actions/upload-artifact@v2
        with:
          name: ${{ steps.config.outputs.target-analysis }}
          path: ${{ steps.config.outputs.target-analysis }}

      - name: Generate summary file (PR only)
        if: github.event_name == 'pull_request'
        run: >
          python helper.py comment-body
          ${{ steps.config.outputs.baseline-analysis }} ${{ steps.config.outputs.target-analysis }}
          ${{ steps.config.outputs.baseline-sha }} ${{ steps.config.outputs.target-sha }}

      - name: Upload summary file (PR only)
        if: github.event_name == 'pull_request'
        uses: actions/upload-artifact@v2
        with:
          name: .pr-comment-body.md
          path: .pr-comment-body.md

        # This is last so the diff-shades-comment workflow can still work even if we
        # end up detecting failed files and failing the run.
      - name: Check for failed files in both analyses
        run: >
          diff-shades show-failed --check --show-log ${{ steps.config.outputs.baseline-analysis }};
          diff-shades show-failed --check --show-log ${{ steps.config.outputs.target-analysis }}