name: Docker Build Smart Logic

on:
  push:
    branches:
      - main
    tags:
      - 'v*'
  workflow_dispatch:


env:
  REGISTRY_HOST: git.pi-farm.de
  IMAGE_BASE: ${{ gitea.repository }}

jobs:
  build:
    name: Build amd64 & arm64
    runs-on: buildx-multiarch

    steps:
      - name: Checkout repository
        uses: http://git.pi-farm.de/pi-farm/checkout@v4
        with:
          fetch-depth: 0
          fetch-tags: true

      - name: Dynamic Template Fix
        id: template_fix
        run: |
          if grep -q "{{.RepoName}}" README.md 2>/dev/null; then
            echo "Ersetze Platzhalter in README, docker-compose und LICENSE..."
            
            REPO_NAME=$(echo "${{ gitea.repository }}" | cut -d'/' -f2)
            OWNER_NAME=$(echo "${{ gitea.repository }}" | cut -d'/' -f1)
            BRANCH_NAME="${{ gitea.ref_name }}"
            
            sed -i "s|{{.RepoName}}|${REPO_NAME}|g" README.md docker-compose.yml LICENSE 2>/dev/null || true
            sed -i "s|{{.OwnerName}}|${OWNER_NAME}|g" README.md docker-compose.yml LICENSE 2>/dev/null || true
            sed -i "s|{{.BranchName}}|${BRANCH_NAME}|g" README.md docker-compose.yml LICENSE 2>/dev/null || true

            git config user.name "Gitea Bot"
            git config user.email "bot@gitea.local"
            git add README.md docker-compose.yml LICENSE
            
            if git diff --staged --quiet; then
              echo "Keine Änderungen zum Committen."
            else
              git commit -m "docs: fix template placeholders [skip ci]"
              git push origin HEAD:${{ gitea.ref_name }}
            fi
          else
            echo "Platzhalter bereits ersetzt."
          fi

      - name: Detect version context
        run: |
          echo "REF=${{ gitea.ref }}" 
          echo "REF_NAME=${{ gitea.ref_name }}"
          echo "REF_TYPE=${{ gitea.ref_type }}"

          if [ "${{ gitea.ref_type }}" = "tag" ]; then
            VERSION="${{ gitea.ref_name }}"
            CLEAN_VERSION="${VERSION#v}"
            IS_TAG=true
          else
            VERSION="edge"
            CLEAN_VERSION="edge"
            IS_TAG=false
          fi

          echo "VERSION=$VERSION" >> $GITEA_ENV
          echo "CLEAN_VERSION=$CLEAN_VERSION" >> $GITEA_ENV
          echo "IS_TAG=$IS_TAG" >> $GITEA_ENV

      - name: Set dynamic variables and check Dockerfiles
        id: check_files
        run: |
          if [ -s "Dockerfile" ]; then
            echo "Dockerfile gefunden und nicht leer. Build wird vorbereitet."
            echo "should_build=true" >> $GITEA_OUTPUT
          else
            echo "Dockerfile ist leer oder fehlt. Build wird übersprungen."
            echo "should_build=false" >> $GITEA_OUTPUT
            exit 0
          fi

          AMD64_FILE="Dockerfile"
          if [ -s "Dockerfile.aarch64" ]; then
            echo "Spezielles Dockerfile.aarch64 erkannt."
            ARM64_FILE="Dockerfile.aarch64"
          else
            ARM64_FILE="Dockerfile"
          fi

          echo "IMAGE_NAME=${{ env.REGISTRY_HOST }}/${{ env.IMAGE_BASE }}" >> $GITEA_ENV
          echo "CACHE_IMAGE_NAME=${{ env.REGISTRY_HOST }}/${{ env.IMAGE_BASE }}-cache" >> $GITEA_ENV
          echo "AMD64_DOCKERFILE=$AMD64_FILE" >> $GITEA_ENV
          echo "ARM64_DOCKERFILE=$ARM64_FILE" >> $GITEA_ENV
          echo "BUILD_DATE=$(date -u +%Y-%m-%dT%H:%M:%SZ)" >> $GITEA_ENV

      - name: Login to registry
        if: steps.check_files.outputs.should_build == 'true'
        run: |
          echo "${{ secrets.REGISTRY_PASSWORD }}" | docker login \
            ${{ env.REGISTRY_HOST }} -u ${{ secrets.REGISTRY_USER }} --password-stdin

      - name: Setup buildx
        if: steps.check_files.outputs.should_build == 'true'
        run: |
          docker buildx rm multiarch || true
          docker buildx create --name multiarch --driver docker-container --use
          docker buildx inspect --bootstrap

      - name: Compute Docker tags
        run: |
          TAGS="${IMAGE_NAME}:${VERSION}"

          if [[ "$IS_TAG" == "true" ]]; then
            MAJOR=$(echo $CLEAN_VERSION | cut -d. -f1)
            MINOR=$(echo $CLEAN_VERSION | cut -d. -f1,2)

            TAGS="$TAGS,${IMAGE_NAME}:${MINOR}"
            TAGS="$TAGS,${IMAGE_NAME}:${MAJOR}"
            TAGS="$TAGS,${IMAGE_NAME}:latest"
          else
            TAGS="$TAGS,${IMAGE_NAME}:main"
          fi

          echo "DOCKER_TAGS=$TAGS" >> $GITEA_ENV

      - name: Build & push multiarch
        if: steps.check_files.outputs.should_build == 'true'
        run: |
          IFS=',' read -ra TAGARRAY <<< "$DOCKER_TAGS"
          TAG_ARGS=""
          for tag in "${TAGARRAY[@]}"; do
            TAG_ARGS="$TAG_ARGS -t $tag"
          done

          docker buildx build \
            --platform linux/amd64,linux/arm64 \
            -f ${AMD64_DOCKERFILE} \
            --build-arg BUILD_DATE=${BUILD_DATE} \
            --build-arg VERSION=${VERSION} \
            $TAG_ARGS \
            --push .