# The GitHub Actions docs (https://docs.github.com/en/actions/reference/workflow-syntax-for-github-actions#on)
# describe other options for 'on', 'pull_request' is a good default.
on: [pull_request]
env:
  # If you use private modules you'll need this env variable to use
  # the same ssh-agent socket value across all jobs & steps.
  SSH_AUTH_SOCK: /tmp/ssh_agent.sock
jobs:
  infracost:
    name: Infracost
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: write

    env:
      TF_ROOT: examples/terraform-project/code
      # If you're using Terraform Cloud/Enterprise and have variables or private modules stored
      # on there, specify the following to automatically retrieve the variables:
      #   INFRACOST_TERRAFORM_CLOUD_TOKEN: ${{ secrets.TFC_TOKEN }}
      #   INFRACOST_TERRAFORM_CLOUD_HOST: app.terraform.io # Change this if you're using Terraform Enterprise

    steps:
      # If you use private modules, add an environment variable or secret
      # called GIT_SSH_KEY with your private key, so Infracost can access
      # private repositories (similar to how Terraform/Terragrunt does).
      # - name: add GIT_SSH_KEY
      #   run: |
      #     ssh-agent -a $SSH_AUTH_SOCK
      #     mkdir -p ~/.ssh
      #     echo "${{ secrets.GIT_SSH_KEY }}" | tr -d '\r' | ssh-add -
      #     ssh-keyscan github.com >> ~/.ssh/known_hosts

      - name: Setup Infracost
        uses: infracost/actions/setup@v2
        # See https://github.com/infracost/actions/tree/master/setup for other inputs
        # If you can't use this action, see Docker images in https://infracost.io/cicd
        with:
          api-key: ${{ secrets.INFRACOST_API_KEY }}

      # Checkout the base branch of the pull request (e.g. main/master).
      - name: Checkout base branch
        uses: actions/checkout@v3
        with:
          ref: '${{ github.event.pull_request.base.ref }}'

      # Generate Infracost JSON file as the baseline.
      - name: Generate Infracost cost estimate baseline
        run: |
          infracost breakdown --path=${TF_ROOT} \
                              --format=json \
                              --out-file=/tmp/infracost-base.json

      # Checkout the current PR branch so we can create a diff.
      - name: Checkout PR branch
        uses: actions/checkout@v3

      # Generate an Infracost diff and save it to a JSON file.
      - name: Generate Infracost diff
        run: |
          infracost diff --path=${TF_ROOT} \
                          --format=json \
                          --compare-to=/tmp/infracost-base.json \
                          --out-file=/tmp/infracost.json

      # Posts a comment to the PR using the 'update' behavior.
      # This creates a single comment and updates it. The "quietest" option.
      # The other valid behaviors are:
      #   delete-and-new - Delete previous comments and create a new one.
      #   hide-and-new - Minimize previous comments and create a new one.
      #   new - Create a new cost estimate comment on every push.
      # See https://www.infracost.io/docs/features/cli_commands/#comment-on-pull-requests for other options.
      - name: Post Infracost comment
        run: |
            infracost comment github --path=/tmp/infracost.json \
                                     --repo=$GITHUB_REPOSITORY \
                                     --github-token=${{github.token}} \
                                     --pull-request=${{github.event.pull_request.number}} \
                                     --behavior=update