opencode-slash-command.yml

name: OpenCode Slash Command

on:
  issue_comment:
    types: [created]

permissions:
  contents: read
  pull-requests: write
  issues: write

jobs:
  run:
    name: OpenCode /oc command
    if: |
      github.event.issue.pull_request &&
      startsWith(github.event.comment.body, '/oc') &&
      github.event.comment.author_association == 'OWNER'
    runs-on: ubuntu-latest

    steps:
      - name: Generate app token
        uses: actions/create-github-app-token@v3
        id: app-token
        with:
          client-id: ${{ secrets.APP_ID }}
          private-key: ${{ secrets.APP_PRIVATE_KEY }}

      - name: Acknowledge command
        env:
          GH_TOKEN: ${{ steps.app-token.outputs.token }}
        run: |
          gh api \
            "repos/${{ github.repository }}/issues/comments/${{ github.event.comment.id }}/reactions" \
            -X POST \
            -f content='rocket'

      - name: Fetch PR metadata
        id: pr
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          PR: ${{ github.event.issue.number }}
        run: |
          set -euo pipefail
          mkdir -p .review

          # Full PR data as JSON for OpenCode context
          gh pr view "$PR" --json title,body,labels,baseRefName > .review/pr.json

          # PR diff for analysis
          gh pr diff "$PR" > .review/patch.diff

          # PR title for the OpenCode prompt
          PR_TITLE=$(gh pr view "$PR" --json title -q '.title')
          echo "title=$PR_TITLE" >> "$GITHUB_OUTPUT"

      # Checkout dev (the fixed base branch for renovate PRs). PR head code is
      # untrusted and must not be executed. We only need the repo's tooling and
      # workflow definitions; all PR content is accessed via the GitHub API.
      - name: Checkout trusted base (dev)
        uses: actions/checkout@v7
        with:
          ref: dev
          persist-credentials: false

      - name: Extract prompt
        id: prompt
        env:
          BODY: ${{ github.event.comment.body }}
        run: |
          # Strip the "/oc" command prefix, then one optional leading space.
          PROMPT="${BODY#/oc}"
          PROMPT="${PROMPT# }"
          {
            echo 'text<<OC_PROMPT_DELIM'
            printf '%s\n' "$PROMPT"
            echo 'OC_PROMPT_DELIM'
          } >> "$GITHUB_OUTPUT"

      - name: Guard against empty prompt
        if: steps.prompt.outputs.text == ''
        env:
          GH_TOKEN: ${{ steps.app-token.outputs.token }}
        run: |
          gh api \
            "repos/${{ github.repository }}/issues/${{ github.event.issue.number }}/comments" \
            -X POST \
            -f body='Usage: `/oc <task description>` — provide a task for OpenCode to perform on this PR.'
          echo "Empty /oc prompt; exiting." >&2
          exit 1

      - name: Install OpenCode CLI
        run: |
          set -euo pipefail
          curl -fsSL https://opencode.ai/install | bash
          echo "$HOME/.opencode/bin" >> "$GITHUB_PATH"

      - name: Assemble OpenCode prompt
        run: |
          cat > .review/oc-prompt.md << 'PROMPT_EOF'
          You are assisting with a task on the local-stack infrastructure repository.
          You have access to the `gh` CLI authenticated via GH_TOKEN to interact
          with GitHub (create issues, comment, review, etc.).

          PR context:
          - Repository: ${{ github.repository }}
          - PR number: ${{ github.event.issue.number }}
          - PR title: ${{ steps.pr.outputs.title }}
          - PR diff is available at .review/patch.diff
          - PR metadata is available at .review/pr.json

          Read the PR diff and metadata files to understand the changes before
          acting on the task below.

          ## Task
          PROMPT_EOF
          printf '%s\n' "${{ steps.prompt.outputs.text }}" >> .review/oc-prompt.md

      - name: Run OpenCode
        env:
          OPENCODE_API_KEY: ${{ secrets.OPENCODE_API_KEY }}
          GH_TOKEN: ${{ steps.app-token.outputs.token }}
        run: |
          opencode run \
            --title "OpenCode /oc command for PR #${{ github.event.issue.number }}" \
            --model opencode/deepseek-v4-flash \
            < .review/oc-prompt.md