name: Release

# Single pipeline: lint + test + build, then (only on push to main and
# only if every gate passed) tag the release from the VERSION file.
# A tag is therefore never created unless the build and tests are green.
#
# Why no actions/checkout + actions/setup-go:
#   act_runner re-clones every third-party JS action from github.com per
#   job. setup-go is large and that clone routinely hangs / times out on
#   the homelab runner. We avoid the failure mode entirely by doing the
#   checkout with plain git and downloading Go directly from go.dev.
#   /usr/local/go persists across jobs in the host-executor runner
#   container, so subsequent runs are no-ops.
#
# Tagging token:
#   Pushing a tag needs write access. Gitea injects a per-job
#   `github.token`; this workflow uses it, so the repository's
#   Settings → Actions → General → "Workflow permissions" must allow
#   read/write. If your instance restricts the auto token, set a PAT
#   secret named RELEASE_TAG_PAT (repo write) and it is used instead.

on:
  push:
    branches: [main]
  pull_request:
  workflow_dispatch:

env:
  GO_VERSION: "1.26.3"
  ERRCHECK_VERSION: "v1.20.0"
  STATICCHECK_VERSION: "v0.7.0"

jobs:
  release:
    runs-on: self-hosted
    defaults:
      run:
        shell: sh
    env:
      # Gitea auto-generates a per-job read-scoped token for git fetch;
      # RELEASE_TAG_PAT (if set) is preferred for the tag push.
      GITHUB_TOKEN: ${{ github.token }}
      RELEASE_TAG_PAT: ${{ secrets.RELEASE_TAG_PAT }}
    steps:
      - name: Install Go and toolchain
        run: |
          set -eu
          missing=""
          command -v curl >/dev/null 2>&1 || missing="$missing curl"
          command -v gcc  >/dev/null 2>&1 || missing="$missing build-base"
          command -v git  >/dev/null 2>&1 || missing="$missing git"
          if [ -n "$missing" ]; then
            apk add --no-cache $missing
          fi
          want="go${GO_VERSION}"
          have="$(/usr/local/go/bin/go env GOVERSION 2>/dev/null || echo none)"
          if [ "$have" != "$want" ]; then
            echo "installing Go ${GO_VERSION} (had: ${have})"
            curl -fsSL "https://go.dev/dl/go${GO_VERSION}.linux-amd64.tar.gz" -o /tmp/go.tgz
            rm -rf /usr/local/go
            tar -C /usr/local -xzf /tmp/go.tgz
            rm -f /tmp/go.tgz
          else
            echo "Go ${GO_VERSION} already installed"
          fi
          echo "/usr/local/go/bin" >> "$GITHUB_PATH"
          echo "$HOME/go/bin" >> "$GITHUB_PATH"
          echo "CGO_ENABLED=1" >> "$GITHUB_ENV"

      - name: Checkout
        run: |
          set -eu
          cd "$GITHUB_WORKSPACE"
          rm -rf ./* ./.[!.]* 2>/dev/null || true
          git init -q
          git remote add origin "${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}.git"
          auth=$(printf '%s' "x-access-token:${GITHUB_TOKEN}" | base64 -w0)
          git -c "http.extraheader=Authorization: Basic ${auth}" \
              fetch --depth=1 origin "${GITHUB_SHA}"
          git checkout -q FETCH_HEAD

      - name: Install linters (errcheck, staticcheck)
        run: |
          set -eu
          if ! command -v errcheck >/dev/null 2>&1; then
            echo "installing errcheck ${ERRCHECK_VERSION}"
            go install "github.com/kisielk/errcheck@${ERRCHECK_VERSION}"
          else
            echo "errcheck already installed"
          fi
          if ! command -v staticcheck >/dev/null 2>&1; then
            echo "installing staticcheck ${STATICCHECK_VERSION}"
            go install "honnef.co/go/tools/cmd/staticcheck@${STATICCHECK_VERSION}"
          else
            echo "staticcheck already installed: $(staticcheck -version)"
          fi

      - name: gofmt
        run: |
          set -eu
          diff=$(gofmt -l $(find . -name '*.go' -not -path './vendor/*'))
          if [ -n "$diff" ]; then
            echo "gofmt would reformat:"
            echo "$diff"
            exit 1
          fi

      - name: go vet
        run: go vet ./...

      - name: errcheck
        run: errcheck ./...

      - name: staticcheck
        run: staticcheck ./...

      - name: go test -race
        run: go test ./... -race

      - name: go build
        run: go build ./...

      # ── Release: only on push to main, and only after every gate above
      #    passed (steps run sequentially and fail-fast). ──────────────
      - name: Tag release from VERSION
        if: ${{ github.event_name == 'push' && github.ref == 'refs/heads/main' }}
        run: |
          set -eu
          cd "$GITHUB_WORKSPACE"

          token="${RELEASE_TAG_PAT:-$GITHUB_TOKEN}"
          if [ -z "$token" ]; then
            echo "no token available to push tags" >&2
            exit 1
          fi
          auth=$(printf '%s' "x-access-token:${token}" | base64 -w0)

          # Fetch existing tags so we can check the target tag.
          git -c "http.extraheader=Authorization: Basic ${auth}" \
              fetch --quiet --tags origin || true

          version="$(tr -d ' \t\r\n' < VERSION)"
          if [ -z "$version" ]; then
            echo "VERSION file is empty" >&2
            exit 1
          fi
          tag="v${version}"

          if git rev-parse -q --verify "refs/tags/${tag}" >/dev/null; then
            echo "Tag ${tag} already exists — nothing to release."
            exit 0
          fi
          if git -c "http.extraheader=Authorization: Basic ${auth}" \
                 ls-remote --tags origin "refs/tags/${tag}" | grep -q "${tag}"; then
            echo "Tag ${tag} already exists on the remote — nothing to release."
            exit 0
          fi

          echo "Creating tag ${tag} at ${GITHUB_SHA}"
          git config user.name  "sherlock-release"
          git config user.email "release@sherlock.local"
          git tag -a "${tag}" -m "Release ${tag}"
          git -c "http.extraheader=Authorization: Basic ${auth}" \
              push origin "refs/tags/${tag}"
          echo "Pushed ${tag}."