name: Build & push image

# Builds the Gadfly reviewer container and pushes it to the Gitea container
# registry. Mirrors mort-ci.yml's build-and-push (BuildKit secrets for private
# module access + the LAN --add-host so the builder can reach the registry).
#
#   push to main      -> :latest + :sha-<short>
#   push tag v*       -> :<tag> + :latest
#   other branch push -> :branch-<safe> + :sha-<short>
#   pull_request       -> build only (no push), as a sanity check
#
# Required repo secrets:
#   REGISTRY_USER / REGISTRY_PASSWORD  Gitea creds with registry push + read
#                                      access to the private majordomo module.
# Optional:
#   DISCORD_WEBHOOK_URL  build notifications (unset => silent).

on:
  push:
    branches: [main]
    tags: ["v*"]
    # Docs/example-only changes don't change the image — skip the rebuild.
    # (Path filters are not applied to tag pushes, so `v*` releases always build.)
    paths-ignore:
      - "**.md"
      - "examples/**"
      - "LICENSE"
      - ".gitignore"
      - ".dockerignore"
  pull_request:
    types: [opened, synchronize, reopened]
    paths-ignore:
      - "**.md"
      - "examples/**"
      - "LICENSE"
      - ".gitignore"
      - ".dockerignore"
  workflow_dispatch: {}

concurrency:
  group: gadfly-image-${{ github.ref }}
  cancel-in-progress: true

env:
  IMAGE_NAME: gitea.stevedudenhoeffer.com/steve/gadfly

jobs:
  build-and-push:
    runs-on: ubuntu-latest
    timeout-minutes: 20
    steps:
      - uses: actions/checkout@v4

      - name: Set up Docker Buildx
        run: docker buildx create --use --name gadfly-builder --driver docker-container 2>/dev/null || docker buildx use gadfly-builder

      - name: Log in to the registry
        if: github.event_name != 'pull_request'
        env:
          REGISTRY_USER: ${{ secrets.REGISTRY_USER }}
          REGISTRY_PASSWORD: ${{ secrets.REGISTRY_PASSWORD }}
        run: echo "${REGISTRY_PASSWORD}" | docker login gitea.stevedudenhoeffer.com -u "${REGISTRY_USER}" --password-stdin

      - name: Compute tags
        id: meta
        run: |
          SHA_SHORT=$(echo "${GITHUB_SHA}" | cut -c1-7)
          PUSH=true
          if [ "${{ github.event_name }}" = "pull_request" ]; then
            # Build-only sanity check; nothing published.
            TAGS="${IMAGE_NAME}:pr-${{ github.event.pull_request.number }}"
            PUSH=false
          elif [ "${{ github.ref_type }}" = "tag" ]; then
            TAGS="${IMAGE_NAME}:${GITHUB_REF_NAME},${IMAGE_NAME}:latest"
          elif [ "${GITHUB_REF_NAME}" = "main" ]; then
            TAGS="${IMAGE_NAME}:latest,${IMAGE_NAME}:sha-${SHA_SHORT}"
          else
            BRANCH_SAFE=$(echo "${GITHUB_REF_NAME}" | sed 's/[^a-zA-Z0-9._-]/-/g; s/--*/-/g; s/^-//; s/-$//')
            TAGS="${IMAGE_NAME}:branch-${BRANCH_SAFE},${IMAGE_NAME}:sha-${SHA_SHORT}"
          fi
          echo "tags=${TAGS}" >> "$GITHUB_OUTPUT"
          echo "push=${PUSH}" >> "$GITHUB_OUTPUT"
          echo "Tags: ${TAGS} (push=${PUSH})"

      - name: Notify Discord (started)
        if: github.event_name != 'pull_request'
        env:
          WEBHOOK_URL: ${{ secrets.DISCORD_WEBHOOK_URL }}
        run: |
          [ -z "$WEBHOOK_URL" ] && exit 0
          MSG="🪰 Gadfly image build #${{ github.run_number }} started on \`${{ github.ref_name }}\` (${{ github.sha }})."
          curl -sS -H 'Content-Type: application/json' -d "{\"content\": \"$MSG\"}" "$WEBHOOK_URL" || true

      - name: Build and push
        env:
          REGISTRY_USER: ${{ secrets.REGISTRY_USER }}
          REGISTRY_PASSWORD: ${{ secrets.REGISTRY_PASSWORD }}
        run: |
          TAG_FLAGS=""
          IFS=',' read -ra TAG_ARRAY <<< "${{ steps.meta.outputs.tags }}"
          for tag in "${TAG_ARRAY[@]}"; do TAG_FLAGS="$TAG_FLAGS --tag $tag"; done

          PUSH_FLAG="--push"
          [ "${{ steps.meta.outputs.push }}" = "false" ] && PUSH_FLAG="--output=type=cacheonly"

          docker buildx build \
            $PUSH_FLAG \
            --platform linux/amd64 \
            $TAG_FLAGS \
            --add-host gitea.stevedudenhoeffer.com:192.168.0.134 \
            --secret id=REGISTRY_USER,env=REGISTRY_USER \
            --secret id=REGISTRY_PASSWORD,env=REGISTRY_PASSWORD \
            --file ./Dockerfile \
            .

      - name: Notify Discord (result)
        if: always() && github.event_name != 'pull_request'
        env:
          WEBHOOK_URL: ${{ secrets.DISCORD_WEBHOOK_URL }}
        run: |
          [ -z "$WEBHOOK_URL" ] && exit 0
          if [ "${{ job.status }}" = "success" ]; then
            MSG="✅ Gadfly image build #${{ github.run_number }} succeeded. Tags: \`${{ steps.meta.outputs.tags }}\`."
          else
            MSG="❌ Gadfly image build #${{ github.run_number }} failed. Check Actions logs."
          fi
          curl -sS -H 'Content-Type: application/json' -d "{\"content\": \"$MSG\"}" "$WEBHOOK_URL" || true