name: 'Setup NoMount'
description: 'Integrate NoMount VFS hooks (pinned SHA or latest dev) and enable CONFIG_NOMOUNT'

inputs:
  commit:
    description: 'Full immutable NoMount commit SHA (empty = latest dev branch tip)'
    required: false
    default: ''
  kernel_version:
    description: 'Kernel major/minor version (for example, 5.10 or 6.6)'
    required: false
    default: ''

outputs:
  commit:
    description: 'NoMount commit SHA actually integrated'
    value: ${{ steps.integrate.outputs.commit }}

runs:
  using: composite
  steps:
    - name: Integrate NoMount
      id: integrate
      shell: bash
      working-directory: ${{ github.workspace }}/kernel
      env:
        KERNEL_VERSION: ${{ inputs.kernel_version }}
      run: |
        set -euo pipefail

        KERNEL_DIR="${{ github.workspace }}/kernel/common"
        test -d "$KERNEL_DIR/fs" || {
          echo "Kernel source directory does not exist: $KERNEL_DIR" >&2
          exit 1
        }

        requested_commit="${{ inputs.commit }}"

        if [ -z "$requested_commit" ]; then
          # Float mode: latest dev branch tip, captured at run time
          echo "NoMount: no commit pinned, using latest dev branch tip"
          (
            cd "$KERNEL_DIR"
            curl -fsSL --retry 5 --retry-delay 5 --retry-all-errors \
              https://raw.githubusercontent.com/maxsteeel/nomount/refs/heads/dev/kernel/setup.sh | bash -s dev
          )
          actual_commit="$(git -C "$KERNEL_DIR/NoMount" rev-parse HEAD)"
        else
          # Pin mode: fetch the setup script at the exact SHA and verify it landed
          if ! [[ "$requested_commit" =~ ^[0-9a-f]{40}$ ]]; then
            echo "NoMount commit must be a full 40-character SHA." >&2
            exit 2
          fi
          setup_script="${RUNNER_TEMP}/nomount-setup-${requested_commit}.sh"
          curl --fail --location --silent --show-error --retry 5 --retry-delay 5 --retry-all-errors \
            "https://raw.githubusercontent.com/maxsteeel/nomount/${requested_commit}/kernel/setup.sh" \
            --output "$setup_script"
          test -s "$setup_script"
          chmod 0755 "$setup_script"
          (
            cd "$KERNEL_DIR"
            "$setup_script" "$requested_commit"
          )
          actual_commit="$(git -C "$KERNEL_DIR/NoMount" rev-parse HEAD)"
          if [ "$actual_commit" != "$requested_commit" ]; then
            echo "NoMount commit mismatch: expected $requested_commit, got $actual_commit." >&2
            exit 1
          fi
        fi

        if [ ! -L "$KERNEL_DIR/fs/nomount" ]; then
          echo "NoMount integration failed: fs/nomount symlink missing" >&2
          exit 1
        fi

        echo "commit=$actual_commit" >> "$GITHUB_OUTPUT"
        echo "NOMOUNT_COMMIT=$actual_commit" >> "$GITHUB_ENV"
        echo "NoMount integrated (kernel $KERNEL_VERSION, commit $actual_commit)"

    - name: Enable NoMount in kernel defconfig
      uses: ./.github/actions/set-kernel-config
      with:
        config_list: |
          CONFIG_NOMOUNT=y