package gateway

import (
	"bufio"
	"bytes"
	"debug/buildinfo"
	"debug/elf"
	"os"
	"os/exec"
	"path/filepath"
	"regexp"
	"strings"
	"testing"
)

func TestCIActionReferencesAreImmutable(t *testing.T) {
	workflow, err := os.Open(filepath.Join("..", ".gitea", "workflows", "verify.yml"))
	if err != nil {
		t.Fatal(err)
	}
	defer workflow.Close()
	immutable := regexp.MustCompile(`@[0-9a-f]{40}(?:\s+#.*)?$`)
	scanner := bufio.NewScanner(workflow)
	for scanner.Scan() {
		line := strings.TrimSpace(scanner.Text())
		if strings.HasPrefix(line, "- uses:") && !immutable.MatchString(line) {
			t.Errorf("mutable CI action reference: %s", line)
		}
	}
	if err := scanner.Err(); err != nil {
		t.Fatal(err)
	}
}

func TestGatewayLinuxArtifactsAreReproduciblePureGoELF(t *testing.T) {
	first, second := t.TempDir(), t.TempDir()
	for _, output := range []string{first, second} {
		command := exec.Command("make", "-C", "..", "gateway-linux", "DIST_DIR="+output)
		command.Env = append(os.Environ(), "GOCACHE="+filepath.Join(t.TempDir(), "go-cache"))
		if result, err := command.CombinedOutput(); err != nil {
			t.Fatalf("gateway-linux: %v\n%s", err, result)
		}
	}

	for _, architecture := range []struct {
		name    string
		machine elf.Machine
	}{
		{name: "amd64", machine: elf.EM_X86_64},
		{name: "arm64", machine: elf.EM_AARCH64},
	} {
		firstPath := filepath.Join(first, "verse-gateway-linux-"+architecture.name)
		secondPath := filepath.Join(second, "verse-gateway-linux-"+architecture.name)
		firstBytes, err := os.ReadFile(firstPath)
		if err != nil {
			t.Fatal(err)
		}
		secondBytes, err := os.ReadFile(secondPath)
		if err != nil {
			t.Fatal(err)
		}
		if !bytes.Equal(firstBytes, secondBytes) {
			t.Fatalf("linux/%s gateway build is not byte reproducible", architecture.name)
		}
		executable, err := elf.Open(firstPath)
		if err != nil {
			t.Fatalf("linux/%s ELF: %v", architecture.name, err)
		}
		if executable.FileHeader.Machine != architecture.machine {
			_ = executable.Close()
			t.Fatalf("linux/%s machine = %s", architecture.name, executable.FileHeader.Machine)
		}
		if err := executable.Close(); err != nil {
			t.Fatal(err)
		}
		info, err := buildinfo.ReadFile(firstPath)
		if err != nil {
			t.Fatalf("linux/%s Go build info: %v", architecture.name, err)
		}
		settings := make(map[string]string, len(info.Settings))
		for _, setting := range info.Settings {
			settings[setting.Key] = setting.Value
		}
		if settings["GOOS"] != "linux" || settings["GOARCH"] != architecture.name || settings["CGO_ENABLED"] != "0" {
			t.Fatalf("linux/%s build settings = %#v", architecture.name, settings)
		}
	}
}