package auth

import (
	"errors"
	"testing"
	"time"
)

func TestPingHostUsesICMPWhenAvailable(t *testing.T) {
	originalPing := runICMPPing
	originalDial := dialTCP
	t.Cleanup(func() {
		runICMPPing = originalPing
		dialTCP = originalDial
	})

	runICMPPing = func(hostIP string) error {
		if hostIP != "10.0.0.1" {
			t.Fatalf("host = %q", hostIP)
		}
		return nil
	}
	dialTCP = func(address string, timeout time.Duration) error {
		t.Fatal("tcp should not be used when icmp succeeds")
		return nil
	}

	result := PingHost("10.0.0.1")
	if !result.OK {
		t.Fatalf("expected ok, got %#v", result)
	}
	if result.Method != PingMethodICMP {
		t.Fatalf("method = %q", result.Method)
	}
}

func TestPingHostFallsBackToTCPWhenICMPFails(t *testing.T) {
	originalPing := runICMPPing
	originalDial := dialTCP
	t.Cleanup(func() {
		runICMPPing = originalPing
		dialTCP = originalDial
	})

	runICMPPing = func(hostIP string) error {
		return errors.New("ping unavailable: executable file not found")
	}
	dialTCP = func(address string, timeout time.Duration) error {
		if address != "10.0.0.2:22" {
			t.Fatalf("address = %q", address)
		}
		return nil
	}

	result := PingHost("10.0.0.2")
	if !result.OK {
		t.Fatalf("expected ok, got %#v", result)
	}
	if result.Method != PingMethodTCP {
		t.Fatalf("method = %q", result.Method)
	}
}

func TestPingHostFailsWhenBothFail(t *testing.T) {
	originalPing := runICMPPing
	originalDial := dialTCP
	t.Cleanup(func() {
		runICMPPing = originalPing
		dialTCP = originalDial
	})

	runICMPPing = func(hostIP string) error {
		return errors.New("100% packet loss")
	}
	dialTCP = func(address string, timeout time.Duration) error {
		return errors.New("connection refused")
	}

	result := PingHost("10.0.0.3")
	if result.OK {
		t.Fatal("expected failure")
	}
	if result.Error == nil {
		t.Fatal("expected error")
	}
	if result.Method != PingMethodTCP {
		t.Fatalf("method = %q", result.Method)
	}
}

func TestPingHostRequiresHostIP(t *testing.T) {
	result := PingHost("  ")
	if result.OK || result.Error == nil {
		t.Fatalf("expected failure, got %#v", result)
	}
}