name: ci

on:
  push:
    branches: [main]
  pull_request:
  workflow_dispatch:
    inputs:
      dry-run-release:
        description: "Compute release version, do not tag or release"
        type: boolean
        default: false

permissions:
  contents: write
  pull-requests: read

# Cancel any in-flight CI runs for the same branch when a new push lands.
concurrency:
  group: ci-${{ github.ref }}
  cancel-in-progress: true

jobs:
  vet:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: actions/setup-go@v6
        with:
          go-version: '1.22.x'
          check-latest: true
      - uses: actions/cache@v5
        with:
          path: |
            ~/go/pkg/mod
            ~/.cache/go-build
          key: ${{ runner.os }}-go-1.22-${{ hashFiles('**/go.sum') }}
      - run: go vet ./...

  staticcheck:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: actions/setup-go@v6
        with:
          go-version: '1.22.x'
          check-latest: true
      - uses: actions/cache@v5
        with:
          path: |
            ~/go/pkg/mod
            ~/.cache/go-build
          key: ${{ runner.os }}-go-1.22-${{ hashFiles('**/go.sum') }}
      - run: go install honnef.co/go/tools/cmd/staticcheck@v0.7.0
      - run: staticcheck ./...

  govulncheck:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: actions/setup-go@v6
        with:
          go-version: '1.22.x'
          check-latest: true
      - uses: actions/cache@v5
        with:
          path: |
            ~/go/pkg/mod
            ~/.cache/go-build
          key: ${{ runner.os }}-go-1.22-${{ hashFiles('**/go.sum') }}
      - run: go install golang.org/x/vuln/cmd/govulncheck@latest
      - run: govulncheck ./...

  gosec:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: actions/setup-go@v6
        with:
          go-version: '1.22.x'
          check-latest: true
      - uses: actions/cache@v5
        with:
          path: |
            ~/go/pkg/mod
            ~/.cache/go-build
          key: ${{ runner.os }}-go-1.22-${{ hashFiles('**/go.sum') }}
      - run: go install github.com/securego/gosec/v2/cmd/gosec@latest
      - run: gosec -quiet ./...

  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: actions/setup-go@v6
        with:
          go-version: '1.22.x'
          check-latest: true
      - uses: actions/cache@v5
        with:
          path: |
            ~/go/pkg/mod
            ~/.cache/go-build
          key: ${{ runner.os }}-go-1.22-${{ hashFiles('**/go.sum') }}
      - run: go test -race -coverprofile=coverage.out ./...
      - uses: actions/upload-artifact@v7
        with:
          name: coverage
          path: coverage.out

  golangci-lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: actions/setup-go@v6
        with:
          go-version: '1.22.x'
          check-latest: true
      - uses: golangci/golangci-lint-action@v6
        with:
          version: v2.9.0

  # Aggregate gate — depends on every check above. Used as a single required
  # status check in branch protection AND as a dependency for the release job.
  ci-success:
    runs-on: ubuntu-latest
    needs: [vet, staticcheck, govulncheck, gosec, test, golangci-lint]
    if: always()
    steps:
      - name: All checks passed
        if: ${{ !contains(needs.*.result, 'failure') && !contains(needs.*.result, 'cancelled') }}
        run: echo "ci-success"
      - name: At least one check failed
        if: ${{ contains(needs.*.result, 'failure') || contains(needs.*.result, 'cancelled') }}
        run: |
          echo "Failed/cancelled jobs:"
          echo '${{ toJSON(needs) }}'
          exit 1

  # Auto-release fires on every clean push to main (and on manual
  # workflow_dispatch for testing). Computes next SemVer from commit history
  # via lukaszraczylo/semver-generator and creates a GitHub release.
  # oss-telemetry is a pure library, so there are no binaries to publish —
  # consumers `go get github.com/lukaszraczylo/oss-telemetry@<tag>`.
  release:
    needs: ci-success
    if: |
      (github.event_name == 'push' && github.ref == 'refs/heads/main') ||
      github.event_name == 'workflow_dispatch'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
        with:
          fetch-depth: 0   # full history so semver-generator sees all tags + commits

      - uses: actions/setup-go@v6
        with:
          go-version: '1.22.x'
          check-latest: true

      # Action interface from
      # https://github.com/lukaszraczylo/semver-generator/blob/main/action.yml
      #   Inputs:  repository_local: true   (use already-cloned repo)
      #            existing: true           (respect existing tags as base)
      #   Output:  semantic_version         (bare version string, no "v" prefix)
      - name: Compute next SemVer
        id: semver
        uses: lukaszraczylo/semver-generator@v1
        with:
          repository_local: true
          existing: true
          config_file: .semver.yaml

      - name: Check if tag already exists
        id: tag_check
        run: |
          TAG="v${{ steps.semver.outputs.semantic_version }}"
          if git rev-parse "$TAG" >/dev/null 2>&1; then
            echo "exists=true" >> "$GITHUB_OUTPUT"
            echo "Tag $TAG already exists; nothing to release."
          else
            echo "exists=false" >> "$GITHUB_OUTPUT"
            echo "tag=$TAG" >> "$GITHUB_OUTPUT"
          fi

      - name: Dry-run summary
        if: github.event_name == 'workflow_dispatch' && inputs.dry-run-release == true
        run: |
          echo "Would release: v${{ steps.semver.outputs.semantic_version }}"
          echo "Skipping tag + release (dry-run)."

      - name: Tag release
        if: |
          steps.tag_check.outputs.exists == 'false' &&
          (github.event_name != 'workflow_dispatch' || inputs.dry-run-release == false)
        env:
          TAG: ${{ steps.tag_check.outputs.tag }}
        run: |
          git config user.name  "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
          git tag -a "$TAG" -m "Release $TAG"
          git push origin "$TAG"

      - name: Create GitHub Release
        if: |
          steps.tag_check.outputs.exists == 'false' &&
          (github.event_name != 'workflow_dispatch' || inputs.dry-run-release == false)
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          TAG: ${{ steps.tag_check.outputs.tag }}
        run: |
          gh release create "$TAG" \
            --title "$TAG" \
            --generate-notes \
            --verify-tag