name: Find latest OS image
description: Finds the latest OS image of a given type.

inputs:
  imageType:
    description: "Type of image to find. Can be one of [debug, release] or a custom prefix (branch name)."
    required: true

outputs:
  image:
    description: "The latest image of the given type."
    value: ${{ steps.find-latest-image.outputs.image }}

runs:
  using: "composite"
  steps:
    - name: Login to AWS
      uses: aws-actions/configure-aws-credentials@67fbcbb121271f7775d2e7715933280b06314838 # v1.7.0
      with:
        role-to-assume: arn:aws:iam::795746500882:role/GithubConstellationImageFinder
        aws-region: eu-central-1

    - name: Set search prefix
      id: set-search-prefix
      shell: bash
      env:
        image_type: ${{ inputs.imageType }}
      run: |
        if [[ "${image_type}" == "debug" ]]; then
          echo "prefix=debug-v" >> "${GITHUB_OUTPUT}"
        elif [[ "${image_type}" == "release" ]]; then
          echo "prefix=v" >> "${GITHUB_OUTPUT}"
        else
          echo "prefix=${image_type}" >> "${GITHUB_OUTPUT}"
        fi

    - name: Find latest image
      id: find-latest-image
      shell: bash
      env:
        bucket: cdn-constellation-backend
        prefix: constellation/v1/images/${{ steps.set-search-prefix.outputs.prefix }}
      run: |
        newest_debug_image_path=$(aws s3api list-objects-v2 \
          --output text \
          --bucket "${bucket}" \
          --prefix "${prefix}" \
          --query "reverse(sort_by(Contents, &LastModified))[0].Key")
        image=$(basename "${newest_debug_image_path}" .json)
        echo "image=${image}" >> "${GITHUB_OUTPUT}"