name: Publish to Docker Hub

on:
  push:
    branches:
      - main
    tags:
      - "v*"
    paths-ignore:
      - ".github/workflows/**"
  # Use 'released' instead of 'published' so editing/re-publishing old releases
  # does NOT re-trigger this workflow. 'released' fires only on the initial
  # release publication (and pre-release → release transition).
  release:
    types: [released]
  workflow_dispatch:
    inputs:
      version:
        description: "Version tag to build (e.g. 3.8.4)"
        required: true
        type: string
      promote_latest:
        description: "Also tag :latest (only if this is the highest semver)"
        required: false
        type: boolean
        default: false

permissions:
  contents: read
  packages: write

jobs:
  prepare:
    name: Resolve Docker release metadata
    runs-on: ubuntu-latest
    outputs:
      version: ${{ steps.version.outputs.version }}
      promote_latest: ${{ steps.version.outputs.promote_latest }}
      skip: ${{ steps.version.outputs.skip }}
    env:
      IMAGE_NAME: diegosouzapw/omniroute
    steps:
      - name: Checkout
        uses: actions/checkout@v6
        with:
          ref: ${{ github.event_name == 'workflow_dispatch' && format('refs/tags/v{0}', inputs.version) || '' }}
          # Need full tag history for semver comparison when deciding :latest.
          fetch-depth: 0

      - name: Resolve version, latest-promotion, and skip flag
        id: version
        env:
          EVENT_NAME: ${{ github.event_name }}
          REF_NAME: ${{ github.ref_name }}
          REF_TYPE: ${{ github.ref_type }}
          INPUT_VERSION: ${{ inputs.version }}
          PROMOTE_INPUT: ${{ inputs.promote_latest }}
        run: |
          set -euo pipefail

          # 1) Resolve version string from the trigger (all inputs come via env).
          case "$EVENT_NAME" in
            workflow_dispatch)
              VERSION="${INPUT_VERSION#v}"
              ;;
            push)
              if [ "$REF_TYPE" = "tag" ]; then
                VERSION="${REF_NAME#v}"
              else
                # Push to main → build & tag as `main` only. Never touch :latest.
                VERSION="main"
              fi
              ;;
            release)
              VERSION="${REF_NAME#v}"
              ;;
            *)
              VERSION="${REF_NAME#v}"
              ;;
          esac
          # Sanity-check: only allow [A-Za-z0-9._-] in VERSION (defense in depth).
          if ! printf '%s' "$VERSION" | grep -qE '^[A-Za-z0-9._-]+$'; then
            echo "Refusing to use unsafe VERSION value: $VERSION" >&2
            exit 1
          fi
          echo "version=$VERSION" >> "$GITHUB_OUTPUT"

          # 2) Decide whether to promote :latest.
          PROMOTE="false"
          if [ "$VERSION" = "main" ]; then
            PROMOTE="false"
          elif printf '%s' "$VERSION" | grep -qE -- '-(rc|alpha|beta|pre|next)'; then
            echo "Pre-release identifier detected — skipping :latest."
            PROMOTE="false"
          elif [ "$EVENT_NAME" = "workflow_dispatch" ]; then
            PROMOTE="${PROMOTE_INPUT:-false}"
          else
            git fetch --tags --quiet || true
            HIGHEST=$(git tag -l 'v[0-9]*' | sed 's/^v//' | grep -vE -- '-(rc|alpha|beta|pre|next)' | sort -V | tail -1 || echo "")
            if [ -n "$HIGHEST" ] && [ "$VERSION" = "$HIGHEST" ]; then
              PROMOTE="true"
            else
              echo "Version $VERSION is not the highest semver tag (highest=${HIGHEST:-<none>}). Not promoting :latest."
            fi
          fi
          echo "promote_latest=$PROMOTE" >> "$GITHUB_OUTPUT"

          # 3) Skip if this exact version is already published in Docker Hub.
          #    `main` is always rebuilt (mutable floating tag).
          SKIP="false"
          if [ "$VERSION" != "main" ]; then
            if docker manifest inspect "diegosouzapw/omniroute:${VERSION}" >/dev/null 2>&1; then
              echo "Image diegosouzapw/omniroute:${VERSION} already exists on Docker Hub — skipping rebuild."
              SKIP="true"
            fi
          fi
          echo "skip=$SKIP" >> "$GITHUB_OUTPUT"

          echo "Publishing diegosouzapw/omniroute:$VERSION (promote_latest=$PROMOTE, skip=$SKIP)"

  build:
    name: Build Docker (${{ matrix.platform }})
    needs: prepare
    if: needs.prepare.outputs.skip != 'true'
    runs-on: ${{ matrix.runner }}
    strategy:
      fail-fast: false
      matrix:
        include:
          - platform: linux/amd64
            runner: ubuntu-24.04
            arch: amd64
          - platform: linux/arm64
            runner: ubuntu-24.04-arm
            arch: arm64
    env:
      IMAGE_NAME: diegosouzapw/omniroute
      GHCR_IMAGE_NAME: ghcr.io/diegosouzapw/omniroute
    steps:
      - name: Checkout
        uses: actions/checkout@v6
        with:
          ref: ${{ github.event_name == 'workflow_dispatch' && format('refs/tags/v{0}', inputs.version) || '' }}
          fetch-depth: 0

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      - name: Login to Docker Hub
        uses: docker/login-action@v4
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

      - name: Login to GitHub Container Registry
        uses: docker/login-action@v4
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push platform image by digest
        id: build
        uses: docker/build-push-action@v7
        with:
          context: .
          target: runner-base
          platforms: ${{ matrix.platform }}
          outputs: type=image,push-by-digest=true,name-canonical=true,push=true
          tags: |
            ${{ env.IMAGE_NAME }}
            ${{ env.GHCR_IMAGE_NAME }}
          cache-from: type=gha,scope=docker-${{ matrix.arch }}
          cache-to: type=gha,scope=docker-${{ matrix.arch }},mode=max
          no-cache: false
        env:
          DOCKER_BUILDKIT_INLINE_CACHE: 1

      - name: Export digest
        env:
          DIGEST: ${{ steps.build.outputs.digest }}
        run: |
          set -euo pipefail
          mkdir -p /tmp/digests
          digest="${DIGEST#sha256:}"
          touch "/tmp/digests/${digest}"

      - name: Upload digest
        uses: actions/upload-artifact@v7
        with:
          name: digests-${{ matrix.arch }}
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    name: Publish multi-arch manifests
    needs:
      - prepare
      - build
    if: needs.prepare.outputs.skip != 'true'
    runs-on: ubuntu-latest
    env:
      IMAGE_NAME: diegosouzapw/omniroute
      GHCR_IMAGE_NAME: ghcr.io/diegosouzapw/omniroute
      VERSION: ${{ needs.prepare.outputs.version }}
      PROMOTE_LATEST: ${{ needs.prepare.outputs.promote_latest }}
    steps:
      - name: Checkout
        uses: actions/checkout@v6
        with:
          ref: ${{ github.event_name == 'workflow_dispatch' && format('refs/tags/v{0}', inputs.version) || '' }}
          fetch-depth: 0

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      - name: Login to Docker Hub
        uses: docker/login-action@v4
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}

      - name: Login to GitHub Container Registry
        uses: docker/login-action@v4
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Download digests
        uses: actions/download-artifact@v8
        with:
          pattern: digests-*
          path: /tmp/digests
          merge-multiple: true

      - name: Create Docker Hub manifest
        run: |
          set -euo pipefail

          tags=(-t "${IMAGE_NAME}:${VERSION}")
          if [ "$PROMOTE_LATEST" = "true" ]; then
            tags+=(-t "${IMAGE_NAME}:latest")
          fi

          refs=()
          while IFS= read -r digest_file; do
            refs+=("${IMAGE_NAME}@sha256:$(basename "$digest_file")")
          done < <(find /tmp/digests -type f | sort)

          if [ "${#refs[@]}" -eq 0 ]; then
            echo "No image digests were downloaded." >&2
            exit 1
          fi

          docker buildx imagetools create "${tags[@]}" "${refs[@]}"

      - name: Create GHCR manifest
        run: |
          set -euo pipefail

          tags=(-t "${GHCR_IMAGE_NAME}:${VERSION}")
          if [ "$PROMOTE_LATEST" = "true" ]; then
            tags+=(-t "${GHCR_IMAGE_NAME}:latest")
          fi

          refs=()
          while IFS= read -r digest_file; do
            refs+=("${GHCR_IMAGE_NAME}@sha256:$(basename "$digest_file")")
          done < <(find /tmp/digests -type f | sort)

          if [ "${#refs[@]}" -eq 0 ]; then
            echo "No image digests were downloaded." >&2
            exit 1
          fi

          docker buildx imagetools create "${tags[@]}" "${refs[@]}"

      - name: Inspect image
        if: needs.prepare.outputs.version != 'main'
        run: |
          docker buildx imagetools inspect "${IMAGE_NAME}:${VERSION}"

      - name: Update Docker Hub description
        # Only refresh README/description when we actually promote :latest
        # (avoids overwriting from main pushes or back-fill builds).
        if: needs.prepare.outputs.promote_latest == 'true'
        uses: peter-evans/dockerhub-description@v5
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}
          repository: diegosouzapw/omniroute
          short-description: "OmniRoute — Unified AI proxy. Route any LLM through one endpoint."
          readme-filepath: ./README.md