package api

import "testing"

func TestFingerprintsSimilar(t *testing.T) {
	const ua = "Mozilla/5.0 (Macintosh; Intel Mac OS X 14_2) AppleWebKit/605"
	other := "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537"

	tests := []struct {
		name           string
		stored, current map[string]any
		want           bool
	}{
		{
			name:    "identical UA, different IPs counts as same device",
			stored:  map[string]any{"user_agent": ua, "accept_language": "en"},
			current: map[string]any{"user_agent": ua, "accept_language": "fr"},
			want:    true,
		},
		{
			name:    "different UA never matches",
			stored:  map[string]any{"user_agent": ua},
			current: map[string]any{"user_agent": other},
			want:    false,
		},
		{
			name:    "missing UA on current side is treated as mismatch",
			stored:  map[string]any{"user_agent": ua},
			current: map[string]any{},
			want:    false,
		},
		{
			name:    "missing UA on stored side is treated as mismatch",
			stored:  map[string]any{},
			current: map[string]any{"user_agent": ua},
			want:    false,
		},
		{
			name:    "both nil is mismatch (conservative default)",
			stored:  nil,
			current: nil,
			want:    false,
		},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			if got := fingerprintsSimilar(tc.stored, tc.current); got != tc.want {
				t.Errorf("fingerprintsSimilar = %v, want %v", got, tc.want)
			}
		})
	}
}