name: Daily Version Bump

on:
  schedule:
    # 6pm ET (EDT = 22:00 UTC, EST = 23:00 UTC)
    - cron: "0 22 * * *"
    - cron: "0 23 * * *"
  workflow_dispatch: {}

permissions:
  contents: write

jobs:
  notify:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
          fetch-tags: true

      - name: DST guard
        id: dst
        run: |
          HOUR=$(TZ=America/New_York date +%H)
          if [ "$HOUR" != "18" ]; then
            echo "ET hour is $HOUR, not 18 — wrong DST rule fired"
            echo "skip=true" >> "$GITHUB_OUTPUT"
          else
            echo "skip=false" >> "$GITHUB_OUTPUT"
          fi

      - name: Check for changes since last version tag
        if: steps.dst.outputs.skip != 'true'
        id: changes
        run: |
          LAST_TAG=$(git tag -l 'v*' --sort=-v:refname | head -1)
          if [ -z "$LAST_TAG" ]; then
            echo "No previous version tag — using full history"
            COMMITS=$(git log --oneline --pretty=format:"%s")
          else
            COMMITS=$(git log "$LAST_TAG"..HEAD --oneline --pretty=format:"%s")
          fi

          if [ -z "$COMMITS" ]; then
            echo "No new commits since $LAST_TAG"
            echo "has_changes=false" >> "$GITHUB_OUTPUT"
            exit 0
          fi

          echo "has_changes=true" >> "$GITHUB_OUTPUT"

          # Build bullet list from commit messages, skip merge commits
          BULLET_LIST=$(echo "$COMMITS" | grep -v "^Merge" | sed 's/^/• /')
          {
            echo "bullets<<ENDOFBULLETS"
            echo "$BULLET_LIST"
            echo "ENDOFBULLETS"
          } >> "$GITHUB_OUTPUT"

          # Date-based version
          VERSION="v$(date +%Y.%m.%d)"
          echo "version=$VERSION" >> "$GITHUB_OUTPUT"

      - name: Create version tag
        if: steps.dst.outputs.skip != 'true' && steps.changes.outputs.has_changes == 'true'
        run: |
          git tag ${{ steps.changes.outputs.version }}
          git push origin ${{ steps.changes.outputs.version }}

      - name: Post to Slack
        if: steps.dst.outputs.skip != 'true' && steps.changes.outputs.has_changes == 'true'
        env:
          SLACK_BOT_TOKEN: ${{ secrets.SLACK_BOT_TOKEN }}
          SLACK_CHANNEL_ID: ${{ secrets.SLACK_CHANNEL_ID }}
          VERSION: ${{ steps.changes.outputs.version }}
          BULLETS: ${{ steps.changes.outputs.bullets }}
        run: |
          TEXT=$(printf ":rocket: *%s deployed*\n\n%s" "$VERSION" "$BULLETS")
          curl -s -X POST https://slack.com/api/chat.postMessage \
            -H "Authorization: Bearer $SLACK_BOT_TOKEN" \
            -H "Content-Type: application/json" \
            -d "$(jq -n --arg channel "$SLACK_CHANNEL_ID" --arg text "$TEXT" \
              '{channel: $channel, text: $text}')"