name: UDP Destination Regression

on:
  push:
    branches: ['main', 'fix/udp-wildcard-source', 'pr/udp-wildcard-source']
  pull_request:
    paths:
      - 'go-gost/**'
      - '.github/workflows/udp-destination.yml'
  workflow_dispatch:

permissions:
  contents: read

concurrency:
  group: udp-destination-${{ github.ref }}
  cancel-in-progress: true

jobs:
  linux:
    runs-on: ubuntu-24.04
    timeout-minutes: 20
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-go@v5
        with:
          go-version-file: 'go-gost/go.mod'
          cache-dependency-path: |
            go-gost/go.sum
            go-gost/x/go.sum

      - name: Test agent module
        working-directory: go-gost
        run: go test ./...

      - name: Test protocol module
        working-directory: go-gost/x
        run: go test ./...

      - name: Check UDP races
        working-directory: go-gost/x
        run: go test -race ./internal/net/udp ./listener/udp

      - name: Vet UDP implementation
        working-directory: go-gost/x
        run: go vet ./internal/net/udp ./listener/udp

      - name: Build destination regression executable
        working-directory: go-gost/x
        run: |
          go test -c -race -o "$RUNNER_TEMP/udp-destination.test" ./listener/udp
          go test -c -race -o "$RUNNER_TEMP/udp-packet.test" ./internal/net/udp

      - name: Test multiple destinations in isolated network namespace
        run: |
          sudo unshare --net -- sh -eu -c '
            sysctl -qw net.ipv6.conf.all.disable_ipv6=0
            ip link set lo up
            ip addr add 198.18.0.1/32 dev lo
            ip addr add 169.254.1.2/32 dev lo
            ip -6 addr add fd00:1::1/128 dev lo nodad
            ip -6 addr add fd00:2::1/128 dev lo nodad
            ip -6 addr add fd00:3::1/128 dev lo nodad
            for suffix in "" 2; do
              ip link add "mc-tx$suffix" type veth peer name "mc-rx$suffix"
              ip link set "mc-tx$suffix" addrgenmode none up
              ip link set "mc-rx$suffix" addrgenmode none up
              ip -6 addr add fe80::1/64 dev "mc-tx$suffix" nodad
              ip -6 addr add fe80::2/64 dev "mc-rx$suffix" nodad
            done
            ip addr add 198.18.1.1/24 dev mc-tx
            ip addr add 198.18.2.1/24 dev mc-tx2
            export FLUX_TEST_IPV6_ADDRS=fd00:1::1,fd00:2::1,fd00:3::1
            export FLUX_TEST_IPV4_LINK_LOCAL=169.254.1.2
            export FLUX_TEST_MULTICAST_RX=mc-rx FLUX_TEST_MULTICAST_TX=mc-tx
            export FLUX_TEST_MULTICAST_RX2=mc-rx2 FLUX_TEST_MULTICAST_TX2=mc-tx2
            "$1" -test.v -test.timeout=60s -test.count=5
            exec "$2" -test.v -test.timeout=60s -test.count=5
          ' sh "$RUNNER_TEMP/udp-destination.test" "$RUNNER_TEMP/udp-packet.test"

      - name: Build Linux agent
        working-directory: go-gost
        env:
          CGO_ENABLED: '0'
          GOOS: linux
          GOARCH: amd64
        run: go build -trimpath -o "$RUNNER_TEMP/flux-agent" .