on:
  push:
    tags:
      - 'arch-*'

name: Arch

env:
  GPG_KEY_ID: 56C464BAAC421453

jobs:
  build:
    name: Build Kernel
    runs-on: ubuntu-latest
    container: qzed/archlinux
    steps:
    - name: Checkout code
      uses: actions/checkout@v2

    - name: Install build dependencies
      run: |
        # Install makepkg deps
        pacman -Syu --noconfirm
        pacman -S --noconfirm sudo binutils fakeroot grep base-devel git sbsigntools libffi python

    - name: Setup secureboot certificate
      env:
        SB_KEY: ${{ secrets.SURFACE_SB_KEY }}
      run: |
        cd pkg

        # Install the surface secureboot certificate
        echo "$SB_KEY" | base64 -d > arch/kernel/MOK.key
        cp keys/surface.crt arch/kernel/MOK.crt

    - name: Build
      run: |
        cd pkg/arch/kernel

        # Fix permissions (can't makepkg as root)
        echo "nobody ALL=(ALL) NOPASSWD: /usr/bin/pacman" >> /etc/sudoers
        chown -R nobody .

        # Package compression settings (Matches latest Arch)
        export PKGEXT='.pkg.tar.zst'
        export COMPRESSZST=(zstd -c -T0 --ultra -20 -)
        export MAKEFLAGS="-j2"

        # Build
        su nobody --pty -p -s /bin/bash -c 'makepkg -f --syncdeps --skippgpcheck --noconfirm'

    - name: Prepare release
      run: |
        mkdir release
        mv pkg/arch/kernel/*.pkg.tar.zst release

    - name: Sign packages
      env:
        GPG_KEY: ${{ secrets.SURFACE_GPG_KEY }}
      run: |
        cd release

        # import GPG key
        echo "$GPG_KEY" | base64 -d | gpg --import --no-tty --batch --yes
        export GPG_TTY=$(tty)

        # sign packages
        ls *.pkg.tar.zst | xargs -L1 gpg --detach-sign --batch --no-tty -u $GPG_KEY_ID

    - name: Upload artifacts
      uses: actions/upload-artifact@v1
      with:
        name: arch-latest
        path: release

  release:
    name: Publish release
    needs: [build]
    runs-on: ubuntu-latest
    steps:
    - name: Download artifacts
      uses: actions/download-artifact@v1
      with:
        name: arch-latest

    - name: Upload assets
      uses: svenstaro/upload-release-action@v1-release
      with:
        repo_token: ${{ secrets.GITHUB_BOT_TOKEN }}
        file: ./*-latest/*
        tag: ${{ github.ref }}
        overwrite: true
        file_glob: true

  repo:
    name: Update package repository
    needs: [release]
    runs-on: ubuntu-latest
    container: qzed/archlinux
    steps:
    - name: Install dependencies
      run: |
        pacman -Syu --noconfirm
        pacman -S --noconfirm base-devel git

    - name: Download artifacts
      uses: actions/download-artifact@v1
      with:
        name: arch-latest

    - name: Update repository
      env:
        SURFACEBOT_TOKEN: ${{ secrets.GITHUB_BOT_TOKEN }}
        BRANCH_STAGING: u/staging
        GIT_REF: ${{ github.ref }}
      run: |
        repo="https://surfacebot:${SURFACEBOT_TOKEN}@github.com/linux-surface/repo.git"

        # clone package repository
        git clone -b "${BRANCH_STAGING}" "${repo}" repo

        # copy packages
        cp arch-latest/* repo/arch/
        cd repo/arch

        # parse git tag from ref
        GIT_TAG=$(echo $GIT_REF | sed 's|^refs/tags/||g')

        # convert packages into references
        for pkg in $(find . -name '*.pkg.tar.zst'); do
          echo "linux-surface:$GIT_TAG/$(basename $pkg)" > $pkg.blob
          rm $pkg
        done

        # set git identity
        git config --global user.email "surfacebot@users.noreply.github.com"
        git config --global user.name "surfacebot"

        # commit and push
        update_branch="${BRANCH_STAGING}-$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 32 | head -n 1)"
        git switch -c "${update_branch}"
        git add .
        git commit -m "Update Arch Linux kernel"
        git push --set-upstream origin "${update_branch}"