name: Build & Push Docker Images

on:
  push:
    branches: ["main", "master"]
    tags: ["v*.*.*"]
  pull_request:
    branches: ["main", "master"]

env:
  BACKEND_IMAGE: imap-client-backend
  FRONTEND_IMAGE: imap-client-frontend
  # Uses local Gitea registry: <gitea-host>/<namespace>/<image>:tag

jobs:
  build:
    runs-on: docker
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Derive repository context
        id: repo
        shell: bash
        run: |
          set -e
          RAW_REPO="${GITHUB_REPOSITORY:-${GITEA_REPOSITORY:-}}"
          if [ -z "$RAW_REPO" ]; then
            echo "RAW_REPO not set (expected GITHUB_REPOSITORY or GITEA_REPOSITORY)"; exit 1
          fi
          OWNER="${RAW_REPO%%/*}"
            REPO="${RAW_REPO#*/}"
          if [ -z "$OWNER" ] || [ "$OWNER" = "$RAW_REPO" ]; then
            echo "Failed to parse owner from '$RAW_REPO'"; exit 1
          fi
          REG_HOST="${GITEA_SERVER_URL:-${GITHUB_SERVER_URL:-}}"
          if [ -z "$REG_HOST" ]; then
            echo "GITEA_SERVER_URL/GITHUB_SERVER_URL not set"; exit 1
          fi
          REG_HOST="${REG_HOST#http://}"
          REG_HOST="${REG_HOST#https://}"
          REG_HOST="${REG_HOST%%/*}"
          echo "owner=$OWNER" >> $GITHUB_OUTPUT
          echo "repo=$REPO" >> $GITHUB_OUTPUT
          echo "host=$REG_HOST" >> $GITHUB_OUTPUT
          echo "Derived -> host=$REG_HOST owner=$OWNER repo=$REPO"

      - name: Prepare tags
        id: meta
        run: |
          SHA_TAG=sha-${GITHUB_SHA::7}
          echo "sha_tag=$SHA_TAG" >> $GITHUB_OUTPUT
          if [[ "$GITHUB_REF" == refs/heads/main || "$GITHUB_REF" == refs/heads/master ]]; then
            echo "latest_tag=latest" >> $GITHUB_OUTPUT
          fi
          if [[ "$GITHUB_REF" == refs/tags/v* ]]; then
            VERSION_TAG=${GITHUB_REF#refs/tags/}
            echo "version_tag=$VERSION_TAG" >> $GITHUB_OUTPUT
          fi

      - name: Show build plan
        run: |
          echo "Registry host: ${{ steps.repo.outputs.host }}"
          echo "Namespace (owner): ${{ steps.repo.outputs.owner }}"
          echo "Backend image: ${{ steps.repo.outputs.host }}/${{ steps.repo.outputs.owner }}/${BACKEND_IMAGE}"
          echo "Frontend image: ${{ steps.repo.outputs.host }}/${{ steps.repo.outputs.owner }}/${FRONTEND_IMAGE}"

      - name: Login to local Gitea registry
        run: |
          if [ -z "${{ secrets.CR_USERNAME }}" ] || [ -z "${{ secrets.CR_PASSWORD }}" ]; then
            echo "CR_USERNAME / CR_PASSWORD secrets missing"; exit 1
          fi
          echo "${{ secrets.CR_PASSWORD }}" | docker login "${{ steps.repo.outputs.host }}" -u "${{ secrets.CR_USERNAME }}" --password-stdin

      - name: Build backend
        run: |
          BASE="${{ steps.repo.outputs.host }}/${{ steps.repo.outputs.owner }}/${BACKEND_IMAGE}"
          docker build -t ${BASE}:${{ steps.meta.outputs.sha_tag }} ./backend
          if [ -n "${{ steps.meta.outputs.latest_tag }}" ]; then docker tag ${BASE}:${{ steps.meta.outputs.sha_tag }} ${BASE}:latest; fi
          if [ -n "${{ steps.meta.outputs.version_tag }}" ]; then docker tag ${BASE}:${{ steps.meta.outputs.sha_tag }} ${BASE}:${{ steps.meta.outputs.version_tag }}; fi

      - name: Build frontend
        run: |
          BASE="${{ steps.repo.outputs.host }}/${{ steps.repo.outputs.owner }}/${FRONTEND_IMAGE}"
          docker build -t ${BASE}:${{ steps.meta.outputs.sha_tag }} ./frontend
          if [ -n "${{ steps.meta.outputs.latest_tag }}" ]; then docker tag ${BASE}:${{ steps.meta.outputs.sha_tag }} ${BASE}:latest; fi
          if [ -n "${{ steps.meta.outputs.version_tag }}" ]; then docker tag ${BASE}:${{ steps.meta.outputs.sha_tag }} ${BASE}:${{ steps.meta.outputs.version_tag }}; fi

      - name: Push images
        if: github.event_name != 'pull_request'
        run: |
          for IMG in ${BACKEND_IMAGE} ${FRONTEND_IMAGE}; do
            BASE="${{ steps.repo.outputs.host }}/${{ steps.repo.outputs.owner }}/${IMG}"
            docker push ${BASE}:${{ steps.meta.outputs.sha_tag }}
            if [ -n "${{ steps.meta.outputs.latest_tag }}" ]; then docker push ${BASE}:latest; fi
            if [ -n "${{ steps.meta.outputs.version_tag }}" ]; then docker push ${BASE}:${{ steps.meta.outputs.version_tag }}; fi
          done