name: 'Cache Save'
description: 'Save cache as tar.xz archive on the runner filesystem'
inputs:
  path:
    description: 'Directory to cache'
    required: false
    default: ${{ github.workspace }}
  key-prefix:
    description: 'Prefix for the cache key'
    required: true
  key-file:
    description: 'File to hash for the cache key'
    required: true
runs:
  using: "composite"
  steps:
    - name: Save cache
      shell: bash
      run: |
        CACHE_DIR="$HOME/.cache/.cache-store"
        mkdir -p "$CACHE_DIR"

        KEY_HASH=$(sha256sum "${{ inputs.key-file }}" | awk '{print $1}')
        CACHE_KEY="${{ inputs.key-prefix }}-${KEY_HASH}"
        ARCHIVE="${CACHE_DIR}/${CACHE_KEY}.tar.xz"

        EXPANDED_PATH=$(eval echo "${{ inputs.path }}")

        echo "Key file: ${{ inputs.key-file }}"
        echo "Path input: ${{ inputs.path }}"
        echo "Expanded path: ${EXPANDED_PATH}"
        echo "Archive path: ${ARCHIVE}"

        if [ ! -d "$EXPANDED_PATH" ] || [ -z "$(ls -A "$EXPANDED_PATH" 2>/dev/null)" ]; then
          echo "Cache directory empty, skipping save"
          exit 0
        fi

        echo "Saving cache: ${CACHE_KEY}"
        REL_PATH="$(echo "$EXPANDED_PATH" | sed 's|^/||')"
        TMP_ARCHIVE="${ARCHIVE}.tmp"
        if tar -cJf "$TMP_ARCHIVE" -C "/" "$REL_PATH" 2>/dev/null && mv -f "$TMP_ARCHIVE" "$ARCHIVE"; then
          echo "Cache saved"
        else
          rm -f "$TMP_ARCHIVE"
          echo "Cache save failed"
        fi

        # Trim the shared cache store and stale workspaces (best-effort)
        bash "${{ github.action_path }}/prune.sh" || true