name: 'Setup SSH for GitHub'
description: 'Configure SSH for private repository access'
inputs:
  ssh-private-key:
    description: 'SSH private key for repository access'
    required: false
    default: ''
runs:
  using: composite
  steps:
    - name: Generate placeholder SSH private key if SSH auth for private repos is not needed
      id: generate_key
      shell: bash
      run: |
        if [[ -z "${{ inputs.ssh-private-key }}" ]]; then
          ssh-keygen -t ed25519 -C "github-actions" -N "" -f ~/.ssh/id_ed25519
          echo "SSH_PRIVATE_KEY<<EOF" >> $GITHUB_OUTPUT
          cat ~/.ssh/id_ed25519 >> $GITHUB_OUTPUT
          echo "EOF" >> $GITHUB_OUTPUT
        else
          echo "SSH_PRIVATE_KEY<<EOF" >> $GITHUB_OUTPUT
          echo "${{ inputs.ssh-private-key }}" >> $GITHUB_OUTPUT
          echo "EOF" >> $GITHUB_OUTPUT
        fi

    - name: Add private GitHub key to SSH agent
      uses: webfactory/ssh-agent@v0.9.0
      with:
        ssh-private-key: ${{ steps.generate_key.outputs.SSH_PRIVATE_KEY }}