# We use github cache to save snapshots between runs.
# For PRs and MergeQueues, the target commit is used, and for push events, github.event.previous is used.
# If a snapshot for a given Hash is not found, we checkout that commit, run the tests and cache the snapshots.
# These are then downloaded before running the E2E, providing the reference snapshots.
# If there are any errors, the diff image is uploaded to artifacts, and the user is notified.

name: E2E

on:
  push:
    branches-ignore:
      - 'gh-readonly-queue/**'
  pull_request:
  merge_group:

permissions:
  contents: read

env:
  # For PRs and MergeQueues, the target commit is used, and for push events, github.event.previous is used.
  targetHash: ${{ github.event.pull_request.base.sha || github.event.merge_group.base_sha || (github.event.before == '0000000000000000000000000000000000000000' && 'develop' || github.event.before)  }}

jobs:
  cache:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: pnpm/action-setup@v2
      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: 18.x
      - name: Cache snapshots
        id: cache-snapshot
        uses: actions/cache@v4
        with:
          save-always: true
          path: ./cypress/snapshots
          key: ${{ runner.os }}-snapshots-${{ env.targetHash }}

      # If a snapshot for a given Hash is not found, we checkout that commit, run the tests and cache the snapshots.
      - name: Switch to base branch
        if: ${{ steps.cache-snapshot.outputs.cache-hit != 'true' }}
        uses: actions/checkout@v4
        with:
          ref: ${{ env.targetHash }}

      - name: Cypress run
        uses: cypress-io/github-action@v4
        id: cypress-snapshot-gen
        if: ${{ steps.cache-snapshot.outputs.cache-hit != 'true' }}
        with:
          start: pnpm run dev
          wait-on: 'http://localhost:9000'
          browser: chrome

  e2e:
    runs-on: ubuntu-latest
    needs: cache
    strategy:
      fail-fast: false
      matrix:
        node-version: [18.x]
        containers: [1, 2, 3, 4]
    steps:
      - uses: actions/checkout@v4

      - uses: pnpm/action-setup@v2
        # uses version from "packageManager" field in package.json

      - name: Setup Node.js ${{ matrix.node-version }}
        uses: actions/setup-node@v4
        with:
          node-version: ${{ matrix.node-version }}

      # These cached snapshots are downloaded, providing the reference snapshots.
      - name: Cache snapshots
        id: cache-snapshot
        uses: actions/cache/restore@v3
        with:
          path: ./cypress/snapshots
          key: ${{ runner.os }}-snapshots-${{ env.targetHash }}

      # Install NPM dependencies, cache them correctly
      # and run all Cypress tests
      - name: Cypress run
        uses: cypress-io/github-action@v4
        id: cypress
        # If CYPRESS_RECORD_KEY is set, run in parallel on all containers
        # Otherwise (e.g. if running from fork), we run on a single container only
        if: ${{ ( env.CYPRESS_RECORD_KEY != '' ) || ( matrix.containers == 1 ) }}
        with:
          start: pnpm run dev:coverage
          wait-on: 'http://localhost:9000'
          browser: chrome
          # Disable recording if we don't have an API key
          # e.g. if this action was run from a fork
          record: ${{ secrets.CYPRESS_RECORD_KEY != '' }}
          parallel: ${{ secrets.CYPRESS_RECORD_KEY != '' }}
        env:
          CYPRESS_RECORD_KEY: ${{ secrets.CYPRESS_RECORD_KEY }}
          VITEST_COVERAGE: true
          CYPRESS_COMMIT: ${{ github.sha }}

      - name: Upload Coverage to Codecov
        uses: codecov/codecov-action@v3
        # Run step only pushes to develop and pull_requests
        if: ${{ steps.cypress.conclusion == 'success' && (github.event_name == 'pull_request' || github.ref == 'refs/heads/develop')}}
        with:
          files: coverage/cypress/lcov.info
          flags: e2e
          name: mermaid-codecov
          fail_ci_if_error: false
          verbose: true
          token: 6845cc80-77ee-4e17-85a1-026cd95e0766

      # We upload the artifacts into numbered archives to prevent overwriting
      - name: Upload Artifacts
        uses: actions/upload-artifact@v4
        if: ${{ always() }}
        with:
          name: snapshots-${{ matrix.containers }}
          retention-days: 1
          path: ./cypress/snapshots

  combineArtifacts:
    needs: e2e
    runs-on: ubuntu-latest
    if: ${{ always() }}
    steps:
      # Download all snapshot artifacts and merge them into a single folder
      - name: Download All Artifacts
        uses: actions/download-artifact@v4
        with:
          path: snapshots
          pattern: snapshots-*
          merge-multiple: true

      # For successful push events, we save the snapshots cache
      - name: Save snapshots cache
        id: cache-upload
        if: ${{ github.event_name == 'push' && needs.e2e.result != 'failure' }}
        uses: actions/cache/save@v3
        with:
          path: ./snapshots
          key: ${{ runner.os }}-snapshots-${{ github.event.after }}

      - name: Flatten images to a folder
        if: ${{ needs.e2e.result == 'failure'  }}
        run: |
          mkdir errors
          cd snapshots
          find . -mindepth 2 -type d -name "*__diff_output__*" -exec sh -c 'mv "$0"/*.png ../errors/' {} \;

      - name: Upload Error snapshots
        if: ${{ needs.e2e.result == 'failure' }}
        uses: actions/upload-artifact@v4
        id: upload-artifacts
        with:
          name: error-snapshots
          retention-days: 10
          path: errors/

      - name: Notify Users
        if: ${{ needs.e2e.result == 'failure' }}
        run: |
          echo "::error title=Visual tests failed::You can view images that failed by downloading the error-snapshots artifact: ${{ steps.upload-artifacts.outputs.artifact-url }}"