name: Build and Push

on:
  push:
    branches: [main]
    # Don't rebuild on doc-only or CI-config-only changes
    paths-ignore:
      - 'README.md'
      - '.gitea/**'
      - 'deploy/**'
  workflow_dispatch:

env:
  REGISTRY: registry.c5ai.ch
  IMAGE: pieced/pieced-portal

jobs:
  build:
    # 'self-hosted' matches the label our act_runner registers with.
    # 'ubuntu-latest' would work too because we configure both labels in the
    # runner config, but self-hosted makes intent explicit.
    runs-on: ubuntu-latest

    env:
      DOCKER_HOST: tcp://172.17.0.1:2375

    outputs:
      version: ${{ steps.version.outputs.version }}

    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Determine next patch version
        id: version
        # Reads tags from the registry's OCI Distribution v2 API, filters to
        # strict semver (skips 'latest', 'dev', '<sha>-dirty', etc.), picks the
        # highest with version-sort, and bumps the patch component. If nothing
        # numeric exists yet (fresh registry), starts at 0.1.0.
        env:
          REG_USER: ${{ secrets.REGISTRY_USERNAME }}
          REG_PASS: ${{ secrets.REGISTRY_PASSWORD }}
        run: |
          set -euo pipefail
          tags_json=$(curl -sf -u "$REG_USER:$REG_PASS" \
            "https://${REGISTRY}/v2/${IMAGE}/tags/list")
          highest=$(echo "$tags_json" \
            | jq -r '.tags // [] | .[]' \
            | grep -E '^[0-9]+\.[0-9]+\.[0-9]+$' \
            | sort -V \
            | tail -n1 || true)
          if [ -z "$highest" ]; then
            next="0.1.0"
            echo "No semver tags found — starting at $next"
          else
            major=$(echo "$highest" | cut -d. -f1)
            minor=$(echo "$highest" | cut -d. -f2)
            patch=$(echo "$highest" | cut -d. -f3)
            next="${major}.${minor}.$((patch + 1))"
            echo "Highest existing: $highest → next: $next"
          fi
          echo "version=${next}" >> "$GITHUB_OUTPUT"

      - name: Build and push image
        env:
          REG_USER: ${{ secrets.REGISTRY_USERNAME }}
          REG_PASS: ${{ secrets.REGISTRY_PASSWORD }}
          VERSION: ${{ steps.version.outputs.version }}
        run: |
          set -euo pipefail
          mkdir -p /root/.docker
          AUTH=$(printf '%s:%s' "$REG_USER" "$REG_PASS" | base64 -w 0)
          cat > /root/.docker/config.json <<EOF
          {
            "auths": {
              "registry.c5ai.ch": {
                "auth": "${AUTH}"
              },
              "https://registry.c5ai.ch": {
                "auth": "${AUTH}"
              },
              "https://registry.c5ai.ch/v1/": {
                "auth": "${AUTH}"
              }
            }
          }
          EOF

          docker build --pull \
            -t "${REGISTRY}/${IMAGE}:${VERSION}" \
            -t "${REGISTRY}/${IMAGE}:latest" .
          docker push "${REGISTRY}/${IMAGE}:${VERSION}"
          docker push "${REGISTRY}/${IMAGE}:latest"

      - name: Tag git commit with version
        env:
          VERSION: ${{ steps.version.outputs.version }}
        run: |
          set -euo pipefail
          git config user.name "pieced-ci"
          git config user.email "ci@pieced.ch"
          git tag -a "v${VERSION}" -m "Release ${VERSION}"
          # Use CI_TOKEN explicitly so we can push a tag (the workflow's
          # default token may or may not have push scope depending on Gitea
          # actions config — explicit token avoids ambiguity).
          git push \
            "https://oauth2:${{ secrets.CI_TOKEN }}@git.c5ai.ch/pieced/pieced-portal.git" \
            "v${VERSION}"

      - name: Summary
        env:
          VERSION: ${{ steps.version.outputs.version }}
        run: |
          {
            echo "## Build complete: ${VERSION}"
            echo
            echo "**Image:** \`${REGISTRY}/${IMAGE}:${VERSION}\`"
            echo
            echo "Run the **Deploy to GitOps** workflow to roll this version out."
          } >> "$GITHUB_STEP_SUMMARY"