package ratelimit_test

import (
	"testing"

	"git.eeqj.de/sneak/neoirc/internal/ratelimit"
)

func TestNewCreatesLimiter(t *testing.T) {
	t.Parallel()

	limiter := ratelimit.New(1.0, 5)
	defer limiter.Stop()

	if limiter == nil {
		t.Fatal("expected non-nil limiter")
	}
}

func TestAllowWithinBurst(t *testing.T) {
	t.Parallel()

	limiter := ratelimit.New(1.0, 3)
	defer limiter.Stop()

	for i := range 3 {
		if !limiter.Allow("192.168.1.1") {
			t.Fatalf(
				"request %d should be allowed within burst",
				i+1,
			)
		}
	}
}

func TestAllowExceedsBurst(t *testing.T) {
	t.Parallel()

	// Rate of 0 means no token replenishment, only burst.
	limiter := ratelimit.New(0, 3)
	defer limiter.Stop()

	for range 3 {
		limiter.Allow("10.0.0.1")
	}

	if limiter.Allow("10.0.0.1") {
		t.Fatal("fourth request should be denied after burst exhausted")
	}
}

func TestAllowSeparateKeys(t *testing.T) {
	t.Parallel()

	// Rate of 0, burst of 1 — only one request per key.
	limiter := ratelimit.New(0, 1)
	defer limiter.Stop()

	if !limiter.Allow("10.0.0.1") {
		t.Fatal("first request for key A should be allowed")
	}

	if !limiter.Allow("10.0.0.2") {
		t.Fatal("first request for key B should be allowed")
	}

	if limiter.Allow("10.0.0.1") {
		t.Fatal("second request for key A should be denied")
	}

	if limiter.Allow("10.0.0.2") {
		t.Fatal("second request for key B should be denied")
	}
}

func TestLenTracksKeys(t *testing.T) {
	t.Parallel()

	limiter := ratelimit.New(1.0, 5)
	defer limiter.Stop()

	if limiter.Len() != 0 {
		t.Fatalf("expected 0 entries, got %d", limiter.Len())
	}

	limiter.Allow("10.0.0.1")
	limiter.Allow("10.0.0.2")

	if limiter.Len() != 2 {
		t.Fatalf("expected 2 entries, got %d", limiter.Len())
	}

	// Same key again should not increase count.
	limiter.Allow("10.0.0.1")

	if limiter.Len() != 2 {
		t.Fatalf("expected 2 entries, got %d", limiter.Len())
	}
}

func TestStopDoesNotPanic(t *testing.T) {
	t.Parallel()

	limiter := ratelimit.New(1.0, 5)
	limiter.Stop()
}