name: Build and Push Teamspeak Images on Base Image Update

on:
  push:
    branches:
      - main
    paths-ignore:
      - '**/CHANGES.md'
      - '**/build-info.json'
  schedule:
    - cron: '30 */6 * * *'  # Every 6 hours

env:
  IMAGE_REGISTRY: gitea.fithwum.tech
  IMAGE_ORG: fithwum
  IMAGE_REPO_TS: teamspeak-server
  IMAGE_REPO_DEBIAN: debian-base
  IMAGE_TAG_DEBIAN: bookworm
  ALPINE_IMAGE: alpine:latest
  CACHE_DIR: .cache

jobs:
  check-base-images-and-build:
    runs-on: docker-build

    steps:
      - name: Checkout code
        uses: actions/checkout@v3

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Log in to Gitea Registry
        run: echo "${{ secrets.DOCKER_PASSWORD }}" | docker login ${{ env.IMAGE_REGISTRY }} -u "${{ secrets.DOCKER_USERNAME }}" --password-stdin

      - name: Get alpine:latest digest
        id: alpine_digest
        run: |
          docker pull docker.io/library/alpine:latest
          DIGEST=$(docker inspect --format='{{index .RepoDigests 0}}' alpine:latest || echo "unknown")
          echo "digest=$DIGEST" >> $GITHUB_OUTPUT

      - name: Get debian-base:bookworm digest
        id: debian_digest
        run: |
          IMAGE="${{ env.IMAGE_REGISTRY }}/${{ env.IMAGE_ORG }}/${{ env.IMAGE_REPO_DEBIAN }}:${{ env.IMAGE_TAG_DEBIAN }}"
          docker pull "$IMAGE"
          DIGEST=$(docker inspect --format='{{index .RepoDigests 0}}' "$IMAGE" || echo "unknown")
          echo "digest=$DIGEST" >> $GITHUB_OUTPUT

      - name: Compare digests and update .cache
        id: compare_digests
        run: |
          mkdir -p $CACHE_DIR

          check_digest() {
            local name=$1
            local new_digest=$2
            local file="$CACHE_DIR/$name.digest"

            echo "[INFO] Checking $name..."
            if [[ -f $file ]]; then
              old_digest=$(cat "$file")
            else
              old_digest=""
            fi

            if [[ "$old_digest" == "$new_digest" ]]; then
              echo "$name_changed=false" >> $GITHUB_OUTPUT
              echo "[INFO] $name unchanged."
            else
              echo "$new_digest" > "$file"
              echo "$name_changed=true" >> $GITHUB_OUTPUT
              echo "[INFO] $name changed."
            fi
          }

          check_digest "alpine" "${{ steps.alpine_digest.outputs.digest }}"
          check_digest "debian-base" "${{ steps.debian_digest.outputs.digest }}"

          git config user.name "${{ secrets.GIT_USERNAME }}"
          git config user.email "${{ secrets.GIT_EMAIL }}"
          git add $CACHE_DIR
          git commit -m "Update base image digests" || echo "[INFO] No cache changes to commit"
          git push || true

      - name: Build and Push Alpine Image
        if: steps.compare_digests.outputs.alpine_changed == 'true'
        run: |
          IMAGE="${{ env.IMAGE_REGISTRY }}/${{ env.IMAGE_ORG }}/${{ env.IMAGE_REPO_TS }}:alpine"
          echo "[INFO] Building $IMAGE"
          docker buildx build --platform linux/amd64 --push -t "$IMAGE" ./alpine

      - name: Build and Push Debian Image
        if: steps.compare_digests.outputs.debian-base_changed == 'true'
        run: |
          IMAGE="${{ env.IMAGE_REGISTRY }}/${{ env.IMAGE_ORG }}/${{ env.IMAGE_REPO_TS }}:debian"
          echo "[INFO] Building $IMAGE"
          docker buildx build --platform linux/amd64 --push -t "$IMAGE" ./debian

      - name: Build and Push Basic Image (depends on debian)
        if: steps.compare_digests.outputs.debian-base_changed == 'true'
        run: |
          IMAGE="${{ env.IMAGE_REGISTRY }}/${{ env.IMAGE_ORG }}/${{ env.IMAGE_REPO_TS }}:basic"
          echo "[INFO] Building $IMAGE"
          docker buildx build --platform linux/amd64 --push -t "$IMAGE" ./basic

  generate-changelogs:
    needs: check-base-images-and-build
    runs-on: docker-build

    steps:
      - name: Checkout source
        uses: actions/checkout@v3

      - name: Clone Teamspeak repo
        run: |
          git clone https://${{ secrets.GIT_USERNAME }}:${{ secrets.GIT_TOKEN }}@gitea.fithwum.tech/fithwum/teamspeak-server.git upload-repo

      - name: Generate per-version changelogs
        run: |
          cd upload-repo
          for version in alpine basic debian; do
            echo "[INFO] Updating changelog for $version"

            changelog="$version/CHANGES.md"
            mkdir -p "$(dirname "$changelog")"
            touch "$changelog"

            infofile="$version/build-info.json"
            last_commit=""
            if [ -f "$infofile" ]; then
              last_commit=$(jq -r '.commit' "$infofile")
            fi

            echo -e "\n## $(date -u +'%Y-%m-%dT%H:%M:%SZ')" >> "$changelog"
            if [ -n "$last_commit" ]; then
              git log "${last_commit}..HEAD" --pretty=format:"- %s (%an)" | head -n 10 >> "$changelog"
            else
              git log -n 10 --pretty=format:"- %s (%an)" >> "$changelog"
            fi
          done

      - name: Commit and push changelogs if changed
        run: |
          cd upload-repo
          git config user.name "${{ secrets.GIT_USERNAME }}"
          git config user.email "${{ secrets.GIT_EMAIL }}"

          if git status --porcelain | grep .; then
            git add */CHANGES.md
            git commit -m "Update changelogs on $(date -u +'%Y-%m-%dT%H:%M:%SZ')" --no-verify
            git push
          else
            echo "[INFO] No changelog changes to commit."
          fi

  generate-build-info:
    needs: generate-changelogs
    runs-on: docker-build

    steps:
      - name: Checkout source
        uses: actions/checkout@v3

      - name: Clone Teamspeak repo
        run: |
          git clone https://${{ secrets.GIT_USERNAME }}:${{ secrets.GIT_TOKEN }}@gitea.fithwum.tech/fithwum/teamspeak-server.git upload-repo

      - name: Generate build-info.json per version
        run: |
          human_size() {
            local b=$1
            local d=''
            local s=0
            local S=(B KB MB GB TB)
            while ((b >= 1024 && s < ${#S[@]}-1)); do
              d=$((b % 1024))
              b=$((b / 1024))
              s=$((s + 1))
            done
            printf "%s%s\n" "$b" "${S[$s]}"
          }

          cd upload-repo
          for version in alpine basic debian; do
            echo "[INFO] Generating build-info.json for $version"
            mkdir -p "$version"
            infofile="$version/build-info.json"

            image="${{ env.IMAGE_REGISTRY }}/${{ env.IMAGE_ORG }}/${{ env.IMAGE_REPO_TS }}:$version"

            digest=$(docker inspect --format='{{if .RepoDigests}}{{index .RepoDigests 0}}{{else}}unknown{{end}}' "$image" 2>/dev/null || echo "unknown")
            size_bytes=$(docker image inspect "$image" --format='{{.Size}}' 2>/dev/null || echo "0")

            size_bytes=${size_bytes//[^0-9]/}
            if [[ -z "$size_bytes" ]]; then size_bytes=0; fi

            size_human=$(human_size "$size_bytes")

            jq -n \
              --arg version "$version" \
              --arg commit "$(git rev-parse HEAD)" \
              --arg build_time "$(date -u +'%Y-%m-%dT%H:%M:%SZ')" \
              --arg image_tag "$image" \
              --arg digest "$digest" \
              --arg image_size "$size_human" \
              --argjson image_size_bytes "$size_bytes" \
              '{
                version: $version,
                commit: $commit,
                build_time: $build_time,
                image_tag: $image_tag,
                digest: $digest,
                image_size: $image_size,
                image_size_bytes: $image_size_bytes
              }' > "$infofile"
          done

      - name: Commit and push build-info if changed
        run: |
          cd upload-repo
          git config user.name "${{ secrets.GIT_USERNAME }}"
          git config user.email "${{ secrets.GIT_EMAIL }}"

          if git status --porcelain | grep .; then
            git add */build-info.json
            git commit -m "Update build-info on $(date -u +'%Y-%m-%dT%H:%M:%SZ')"
            git push

            # Tag the commit for each version
            for version in alpine basic debian; do
              TAG="build-$version"
              git tag -d "$TAG" 2>/dev/null || true
              git tag "$TAG"
              git push origin "$TAG" --force
            done
          else
            echo "[INFO] No build-info changes to commit."
          fi