name: 'Cache APT Packages'
description: 'Install APT based packages and cache them for future runs.'
author: awalsh128
branding:
  icon: 'hard-drive'  
  color: 'green'

inputs:
  packages:
    description: 'Space delimited list of packages to install.'
    required: true
    default: ''
  version:
    description: 'Version will create a new cache and install packages.'
    required: false
    default: ''  
  refresh:
    description: 'Option to refresh / upgrade the packages in the same cache.'
    required: false
    default: 'false'

outputs:
  cache-hit:
    description: 'A boolean value to indicate a cache was found for the packages requested.'
    # This compound expression is needed because lhs can be empty.
    # Need to output true and false instead of true and nothing.
    value: ${{ steps.load-cache.outputs.cache-hit || false }}
  package-version-list:
    description: 'The packages and versions that are installed as a comma delimited list with colon delimit on the package version (i.e. <package>:<version,<package>:<version>).'
    value: ${{ steps.post-cache.outputs.package-version-list }}

runs:
  using: "composite"
  steps:
    - id: pre-cache
      run: |
        ${{ github.action_path }}/pre_cache_action.sh \
          ~/cache-apt-pkgs \
          "${{ inputs.version }}" \
          ${{ inputs.packages }}
        echo "CACHE_KEY=$(cat ~/cache-apt-pkgs/cache_key.md5)" >> $GITHUB_ENV
      shell: bash

    - id: load-cache
      uses: actions/cache@v2
      with:
        path: ~/cache-apt-pkgs
        key: cache-apt-pkgs_${{ env.CACHE_KEY }}

    - id: post-cache
      run: |      
        ${{ github.action_path }}/post_cache_action.sh \
          ~/cache-apt-pkgs \
          / \
          "${{ steps.load-cache.outputs.cache-hit }}" \
          ${{ inputs.packages }}
        echo "::set-output name=package-version-list::$(cat ~/cache-apt-pkgs/manifest.log)"
      shell: bash