name: Take screenshots

# Regenerates the Web UI screenshots in docs/screenshots/ with shot-scraper and
# commits them back. The screenshots are referenced from README.md and docs/.
#
# What it does: builds the Svelte frontend, boots the FastAPI backend against a
# throwaway fixture volume, drives shot-scraper over shots.yml (one browser per
# shot — see scripts/take_screenshots.py for why), losslessly optimises the PNGs
# with Oxipng, then commits any changes.
#
# Runs on manual dispatch and on pushes that touch the UI. Changes under
# docs/screenshots/** are intentionally NOT a trigger, so the commit this
# workflow makes cannot trigger itself.

on:
  workflow_dispatch:
  push:
    paths:
      - "src/**"
      - "index.html"
      - "svelte.config.js"
      - "vite.config.js"
      - "package.json"
      - "package-lock.json"
      - "shots.yml"
      - "scripts/take_screenshots.py"
      - "scripts/make_screenshot_fixture.sh"
      - ".github/workflows/screenshots.yml"

permissions:
  contents: write

concurrency:
  group: screenshots-${{ github.ref }}
  cancel-in-progress: true

jobs:
  screenshots:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v7

      - name: Set up Node
        uses: actions/setup-node@v4
        with:
          node-version: "22"
          cache: npm

      - name: Set up Python
        uses: actions/setup-python@v5
        with:
          python-version: "3.12"

      - name: Configure pip caching
        uses: actions/cache@v4
        with:
          path: ~/.cache/pip
          key: ${{ runner.os }}-pip-${{ hashFiles('requirements.txt') }}
          restore-keys: ${{ runner.os }}-pip-

      - name: Cache Playwright browsers
        uses: actions/cache@v4
        with:
          path: ~/.cache/ms-playwright/
          key: ${{ runner.os }}-playwright

      - name: Cache Oxipng
        uses: actions/cache@v4
        with:
          path: ~/.cargo/
          key: ${{ runner.os }}-cargo

      - name: Install Oxipng if it is not installed
        run: which oxipng || cargo install oxipng

      - name: Build frontend
        run: |
          npm ci
          npm run build

      - name: Install Python dependencies
        run: |
          pip install -r requirements.txt shot-scraper
          shot-scraper install

      - name: Start the app
        env:
          CHD_MODE: webui
          MAX_CONCURRENT_JOBS: "1"
        run: |
          scripts/make_screenshot_fixture.sh "$RUNNER_TEMP/fixture"
          export COMPRESSATORIUM_MOUNT_ROOT="$RUNNER_TEMP/fixture"
          export STATIC_DIR="$PWD/static"
          export CHD_DATA_DIR="$RUNNER_TEMP/data"
          export CHD_TEMP_DIR="$RUNNER_TEMP/data/temp"
          export PYTHONPATH="$PWD/app"
          mkdir -p "$CHD_DATA_DIR" "$CHD_TEMP_DIR"
          python -m uvicorn main:app --host 127.0.0.1 --port 8099 > "$RUNNER_TEMP/server.log" 2>&1 &
          for i in $(seq 1 30); do
            if curl -sf http://127.0.0.1:8099/health > /dev/null; then
              echo "Server is up"; exit 0
            fi
            sleep 1
          done
          echo "Server did not start in time"; cat "$RUNNER_TEMP/server.log"; exit 1

      - name: Take shots
        run: |
          python scripts/take_screenshots.py shots.yml

      - name: Optimize PNGs
        run: |
          oxipng -o 4 -i 0 --strip safe docs/screenshots/*.png

      - name: Commit and push
        run: |-
          git config user.name "Automated"
          git config user.email "actions@users.noreply.github.com"
          git add docs/screenshots
          timestamp=$(date -u)
          git commit -m "Update Web UI screenshots — ${timestamp}" || exit 0
          git pull --rebase
          git push