# Unified container build workflow
# Triggers on pushes to main that modify containers/*, or via manual dispatch.
# Detects which containers changed and routes to the correct runner:
#   - Dockerfile containers build on k8s (indri) via Dagger
#   - Nix containers build on nix-container-builder (ringtail) via nix-build + skopeo
name: Build Container

on:
  push:
    branches: [main]
    paths: ['containers/**']
  workflow_dispatch:
    inputs:
      container:
        description: 'Container name (directory under containers/)'
        required: true
        type: string
      ref:
        description: 'Commit SHA to build (defaults to current HEAD)'
        required: false
        type: string

jobs:
  detect:
    runs-on: k8s
    outputs:
      dockerfile: ${{ steps.classify.outputs.dockerfile }}
      nix: ${{ steps.classify.outputs.nix }}
    steps:
      - name: Checkout
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          ref: ${{ inputs.ref || github.sha }}
          fetch-depth: 2

      - name: Detect and classify changed containers
        id: classify
        run: |
          if [ "${{ github.event_name }}" = "workflow_dispatch" ]; then
            CHANGED='["${{ inputs.container }}"]'
          else
            CHANGED=$(git diff --name-only HEAD~1 HEAD -- containers/ \
              | cut -d/ -f2 | sort -u \
              | jq -R -s -c 'split("\n") | map(select(length > 0))')
          fi

          echo "Changed containers: $CHANGED"

          # Classify each container by build type (a container can appear in both)
          DOCKERFILE='[]'
          NIX='[]'
          for name in $(echo "$CHANGED" | jq -r '.[]'); do
            has_any=false
            if [ -f "containers/$name/Dockerfile" ]; then
              DOCKERFILE=$(echo "$DOCKERFILE" | jq -c --arg n "$name" '. + [$n]')
              has_any=true
            fi
            if [ -f "containers/$name/default.nix" ]; then
              NIX=$(echo "$NIX" | jq -c --arg n "$name" '. + [$n]')
              has_any=true
            fi
            if [ "$has_any" = "false" ]; then
              echo "Warning: $name has neither Dockerfile nor default.nix — skipping"
            fi
          done

          echo "dockerfile=$DOCKERFILE" >> "$GITHUB_OUTPUT"
          echo "nix=$NIX" >> "$GITHUB_OUTPUT"
          echo "Dockerfile builds: $DOCKERFILE"
          echo "Nix builds: $NIX"

  build-dockerfile:
    needs: detect
    if: needs.detect.outputs.dockerfile != '[]'
    runs-on: k8s
    strategy:
      matrix:
        container: ${{ fromJson(needs.detect.outputs.dockerfile) }}
    steps:
      - name: Checkout
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          ref: ${{ inputs.ref || github.sha }}

      - name: Extract version and SHA
        id: meta
        run: |
          VERSION=$(grep -m1 '^ARG CONTAINER_APP_VERSION=' \
            "containers/${{ matrix.container }}/Dockerfile" \
            | sed 's/^ARG CONTAINER_APP_VERSION=//')

          if [ -z "$VERSION" ]; then
            echo "Error: No CONTAINER_APP_VERSION found in Dockerfile"
            exit 1
          fi

          REF="${{ inputs.ref }}"
          if [ -z "$REF" ]; then
            REF="${GITHUB_SHA}"
          fi
          SHORT_SHA=$(echo "$REF" | head -c 7)

          # Ensure version starts with 'v'
          case "$VERSION" in
            v*) ;;
            *) VERSION="v${VERSION}" ;;
          esac

          echo "version=$VERSION" >> "$GITHUB_OUTPUT"
          echo "sha=$SHORT_SHA" >> "$GITHUB_OUTPUT"
          echo "Version: $VERSION, SHA: $SHORT_SHA"

      - name: Publish
        env:
          ZOT_CI_API_KEY: ${{ secrets.ZOT_CI_API_KEY }}
        run: |
          dagger call publish \
            --src=. \
            --container-name=${{ matrix.container }} \
            --version=${{ steps.meta.outputs.version }} \
            --commit-sha=${{ steps.meta.outputs.sha }} \
            --registry-password=env:ZOT_CI_API_KEY

  build-nix:
    needs: detect
    if: needs.detect.outputs.nix != '[]'
    runs-on: nix-container-builder
    strategy:
      matrix:
        container: ${{ fromJson(needs.detect.outputs.nix) }}
    steps:
      - name: Checkout
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          ref: ${{ inputs.ref || github.sha }}

      - name: Extract version and SHA
        id: meta
        run: |
          CONTAINER="${{ matrix.container }}"
          NIX_FILE="containers/$CONTAINER/default.nix"

          # Extract version = "..." from the nix file
          VERSION=$(grep -m1 '^\s*version\s*=\s*"' "$NIX_FILE" \
            | sed 's/.*"\(.*\)".*/\1/' || true)

          if [ -z "$VERSION" ]; then
            echo "Error: No version declaration found in $NIX_FILE"
            exit 1
          fi

          REF="${{ inputs.ref }}"
          if [ -z "$REF" ]; then
            REF="${GITHUB_SHA}"
          fi
          SHORT_SHA=$(echo "$REF" | head -c 7)

          # Ensure version starts with 'v'
          case "$VERSION" in
            v*) ;;
            *) VERSION="v${VERSION}" ;;
          esac

          echo "version=$VERSION" >> "$GITHUB_OUTPUT"
          echo "sha=$SHORT_SHA" >> "$GITHUB_OUTPUT"
          echo "Version: $VERSION, SHA: $SHORT_SHA"

      - name: Resolve nixpkgs
        id: nixpkgs
        run: |
          NIXPKGS_PATH=$(nix flake metadata nixpkgs --json | jq -r '.path')
          echo "Resolved nixpkgs: $NIXPKGS_PATH"
          echo "path=$NIXPKGS_PATH" >> "$GITHUB_OUTPUT"

      - name: Build with nix
        env:
          NIX_PATH: "nixpkgs=${{ steps.nixpkgs.outputs.path }}"
        run: |
          echo "Building containers/${{ matrix.container }}/default.nix"
          echo "NIX_PATH=$NIX_PATH"
          nix-build "containers/${{ matrix.container }}/default.nix" -o result
          echo "Build complete: $(readlink result)"

      - name: Push to registry
        env:
          ZOT_CI_API_KEY: ${{ secrets.ZOT_CI_API_KEY }}
        run: |
          CONTAINER="${{ matrix.container }}"
          VERSION="${{ steps.meta.outputs.version }}"
          SHORT_SHA="${{ steps.meta.outputs.sha }}"
          IMAGE="registry.ops.eblu.me/blumeops/$CONTAINER:${VERSION}-${SHORT_SHA}-nix"

          echo "Pushing to $IMAGE"
          skopeo copy \
            --dest-creds="zot-ci:$ZOT_CI_API_KEY" \
            "docker-archive:result" \
            "docker://$IMAGE"
          echo "Push complete: $IMAGE"