package stdio

import (
	"os"
	"os/exec"
	"testing"
)

// 1171/AC4: before Serve, a bundle's bus functions still refuse exactly as on main (stdio.go:391-398,
// unchanged for bundles). Run in a fresh process: once any other test in this package has called Serve,
// current stays set for the rest of the test binary, so "before Serve" can only be checked honestly in a
// process of its own (the self-exec pattern Go's own testing package uses for os.Exit).
func TestBusFunctionsRefuseBeforeServeInAFreshProcess(t *testing.T) {
	const marker = "MESH_SDK_TEST_FRESH_PROCESS"
	if os.Getenv(marker) == "1" {
		if err := Emit("x", map[string]any{}); err == nil ||
			err.Error() != "emit before Serve: a bundle emits through the runtime that launched it" {
			t.Fatalf("Emit before Serve: %v", err)
		}
		if _, err := Ask("m.t", nil); err == nil ||
			err.Error() != "before Serve: a bundle reaches the bus through the runtime that launched it" {
			t.Fatalf("Ask before Serve: %v", err)
		}
		if err := Subscribe("x", func(Envelope) error { return nil }); err == nil ||
			err.Error() != "before Serve: a bundle reaches the bus through the runtime that launched it" {
			t.Fatalf("Subscribe before Serve: %v", err)
		}
		return
	}
	cmd := exec.Command(os.Args[0], "-test.run=^TestBusFunctionsRefuseBeforeServeInAFreshProcess$", "-test.v")
	cmd.Env = append(os.Environ(), marker+"=1")
	out, err := cmd.CombinedOutput()
	if err != nil {
		t.Fatalf("a fresh process did not refuse every bus function before Serve: %v\n%s", err, out)
	}
}