name: regen

on:
  schedule:
    - cron: "0 6 * * 1"   # Monday 06:00 UTC
  workflow_dispatch: {}

permissions:
  contents: write
  pull-requests: write

jobs:
  regen:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0   # full history so audit -drift can compare against main

      - name: Set up Go
        uses: actions/setup-go@v5
        with:
          go-version: '1.25.x'
          check-latest: true

      - name: Capture latest snapshot
        id: snapshot
        run: |
          DATE=$(date +%Y-%m-%d)
          DEST="testdata/html/snapshot_${DATE}.html"
          curl -fsSL --user-agent "go-telegram codegen scraper" \
            https://core.telegram.org/bots/api > "$DEST"
          ln -sf "snapshot_${DATE}.html" testdata/html/latest.html
          echo "date=$DATE" >> $GITHUB_OUTPUT
          echo "dest=$DEST" >> $GITHUB_OUTPUT

      - name: Regenerate (scrape + emit, with clean-generated)
        # `make regen` depends on `clean-generated`, which sweeps any orphan
        # api/*.gen.go files left behind by removed/renamed methods.
        run: make regen

      - name: Audit fallbacks
        id: audit
        run: |
          set +e
          OUT=$(make audit 2>&1)
          STATUS=$?
          set -e
          echo "$OUT"
          {
            echo 'output<<EOF'
            echo "$OUT"
            echo 'EOF'
          } >> $GITHUB_OUTPUT
          echo "status=$STATUS" >> $GITHUB_OUTPUT
          # Don't fail the workflow on fallbacks — surface them in the PR body so
          # the reviewer can extend overrides.json or fix scraper patterns.

      - name: Audit drift vs main
        id: drift
        run: |
          set +e
          DRIFT=$(go run ./cmd/audit -ir internal/spec/api.json -drift -against origin/main 2>&1)
          set -e
          echo "$DRIFT"
          {
            echo 'output<<EOF'
            echo "$DRIFT"
            echo 'EOF'
          } >> $GITHUB_OUTPUT

      - name: Run tests
        run: go test -race ./...

      - name: Detect changes
        id: diff
        run: |
          git status --porcelain
          if git diff --quiet internal/spec/api.json api/ testdata/html/; then
            echo "no_changes=true" >> $GITHUB_OUTPUT
          fi

      - name: Read API version
        if: steps.diff.outputs.no_changes != 'true'
        id: meta
        run: |
          VERSION=$(python3 -c 'import json; print(json.load(open("internal/spec/api.json")).get("version", "unknown"))')
          echo "version=$VERSION" >> $GITHUB_OUTPUT

      - name: Open PR
        if: steps.diff.outputs.no_changes != 'true'
        uses: peter-evans/create-pull-request@v7
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          commit-message: |
            chore(api): regenerate from Telegram Bot API v${{ steps.meta.outputs.version }}
          branch: regen/api-v${{ steps.meta.outputs.version }}
          title: "chore(api): regenerate from Telegram Bot API v${{ steps.meta.outputs.version }}"
          labels: automated, api-update
          body: |
            Automated regeneration from `https://core.telegram.org/bots/api`.

            **API version:** v${{ steps.meta.outputs.version }}
            **Snapshot date:** ${{ steps.snapshot.outputs.date }}

            ## Audit (fallbacks)
            ```
            ${{ steps.audit.outputs.output }}
            ```

            ## Drift vs `main`
            ```
            ${{ steps.drift.outputs.output }}
            ```

            Inspect the IR diff (`internal/spec/api.json`) for added/changed/removed methods.

            CI must pass before merge. Auto-merge: enable when satisfied with the diff.