name: Add Dashboard Deprecation Comment

on:
  pull_request_target:
    types: [opened, synchronize]

# All API calls (pulls.listFiles + issues.{list,create,update}Comment) are performed with
# the App token minted below, so the workflow's GITHUB_TOKEN does not need any scopes.
permissions: {}

jobs:
  dashboard-deprecation-comment:
    name: Dashboard deprecation comment
    runs-on: ubuntu-latest
    # Release-bump PRs (bump-X.Y.Z -> beta, beta -> release) inevitably
    # roll up everything merged into dev since the last cut, which can
    # include dashboard changes that have already been reviewed once.
    # The bot's purpose is to warn new contributors before they invest
    # time -- that only applies to PRs entering dev.
    if: github.event.pull_request.base.ref == 'dev'
    steps:
      - name: Generate a token
        id: generate-token
        uses: actions/create-github-app-token@bcd2ba49218906704ab6c1aa796996da409d3eb1 # v3.2.0
        with:
          client-id: ${{ vars.ESPHOME_GITHUB_APP_CLIENT_ID }}
          private-key: ${{ secrets.ESPHOME_GITHUB_APP_PRIVATE_KEY }}
          # pulls.listFiles + issues.{list,create,update}Comment on PRs. For PR resources
          # the issues.*Comment APIs require the pull-requests scope, not issues.
          permission-pull-requests: write

      - name: Add dashboard deprecation comment
        uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
        with:
          github-token: ${{ steps.generate-token.outputs.token }}
          script: |
            const commentMarker = "<!-- This comment was generated automatically by the dashboard-deprecation-comment workflow. -->";

            const commentBody = `Thanks for opening this PR!

            Heads up: the legacy ESPHome dashboard (\`esphome/dashboard/\` and \`tests/dashboard/\`) is **deprecated** and is being replaced by [ESPHome Device Builder](https://github.com/esphome/device-builder). We are not adding new features to the legacy dashboard and it will eventually be removed from this repository.

            What this means for your PR:

            - **New features / enhancements**: please port the change to [esphome/device-builder](https://github.com/esphome/device-builder) instead. We are unlikely to review or merge new dashboard features here.
            - **Bug fixes**: small fixes may still be considered, but please check first whether the same issue exists in Device Builder, where the fix will have a longer life.
            - **Security issues**: please do not file a public PR. Report privately via [GitHub security advisories](https://github.com/esphome/esphome/security/advisories/new) so we can coordinate a fix.

            We appreciate the contribution and apologize for the friction; flagging this early so your time isn't spent on a change that may not land.

            ---
            (Added by the PR bot)

            ${commentMarker}`;

            async function getDashboardChanges(github, owner, repo, prNumber) {
                const changedFiles = await github.paginate(
                    github.rest.pulls.listFiles,
                    {
                        owner: owner,
                        repo: repo,
                        pull_number: prNumber,
                        per_page: 100,
                    }
                );

                return changedFiles.filter(file =>
                    file.filename.startsWith('esphome/dashboard/') ||
                    file.filename.startsWith('tests/dashboard/')
                );
            }

            async function findBotComment(github, owner, repo, prNumber) {
                const comments = await github.paginate(
                    github.rest.issues.listComments,
                    {
                        owner: owner,
                        repo: repo,
                        issue_number: prNumber,
                        per_page: 100,
                    }
                );

                return comments.find(comment =>
                    comment.body.includes(commentMarker) && comment.user.type === "Bot"
                );
            }

            const prNumber = context.payload.pull_request.number;
            const { owner, repo } = context.repo;

            const dashboardChanges = await getDashboardChanges(github, owner, repo, prNumber);
            const existingComment = await findBotComment(github, owner, repo, prNumber);

            if (dashboardChanges.length === 0) {
                // PR doesn't (or no longer) touches the legacy dashboard. If we previously
                // commented (e.g. files were removed in a later push), leave the comment in
                // place for history rather than thrash on edit/delete.
                return;
            }

            if (existingComment) {
                if (existingComment.body === commentBody) {
                    return;
                }
                await github.rest.issues.updateComment({
                    owner: owner,
                    repo: repo,
                    comment_id: existingComment.id,
                    body: commentBody,
                });
            } else {
                await github.rest.issues.createComment({
                    owner: owner,
                    repo: repo,
                    issue_number: prNumber,
                    body: commentBody,
                });
            }