package capture

import (
	"testing"
)

// TestValidateBPFFilter verifies that a valid BPF expression returns nil error.
func TestValidateBPFFilter(t *testing.T) {
	if err := ValidateBPFFilter("port 53"); err != nil {
		t.Errorf("ValidateBPFFilter(\"port 53\") = %v; want nil", err)
	}
}

// TestValidateBPFFilterEmpty verifies that empty string returns nil (no filter).
func TestValidateBPFFilterEmpty(t *testing.T) {
	if err := ValidateBPFFilter(""); err != nil {
		t.Errorf("ValidateBPFFilter(\"\") = %v; want nil", err)
	}
}

// TestValidateBPFFilterWhitespace verifies that whitespace-only string returns nil.
func TestValidateBPFFilterWhitespace(t *testing.T) {
	if err := ValidateBPFFilter("   "); err != nil {
		t.Errorf("ValidateBPFFilter(\"   \") = %v; want nil", err)
	}
}

// TestValidateBPFFilterInvalid verifies that invalid BPF expression returns error.
func TestValidateBPFFilterInvalid(t *testing.T) {
	err := ValidateBPFFilter("invalid garbage xyz")
	if err == nil {
		t.Error("ValidateBPFFilter(\"invalid garbage xyz\") = nil; want non-nil error")
	}
}

// TestCompileSoftwareBPF verifies that a valid expression compiles to a non-nil VM.
func TestCompileSoftwareBPF(t *testing.T) {
	vm, err := CompileSoftwareBPF("tcp")
	if err != nil {
		t.Errorf("CompileSoftwareBPF(\"tcp\") error: %v", err)
	}
	if vm == nil {
		t.Error("CompileSoftwareBPF(\"tcp\") returned nil VM; want non-nil")
	}
}

// TestCompileSoftwareBPFInvalid verifies that invalid expression returns nil VM and non-nil error.
func TestCompileSoftwareBPFInvalid(t *testing.T) {
	vm, err := CompileSoftwareBPF("invalid garbage")
	if err == nil {
		t.Error("CompileSoftwareBPF(\"invalid garbage\") error = nil; want non-nil")
	}
	if vm != nil {
		t.Error("CompileSoftwareBPF(\"invalid garbage\") VM non-nil; want nil")
	}
}