package dispatcher

import (
	"testing"
)

func TestClassify(t *testing.T) {
	tests := []struct {
		name string
		data []byte
		want Protocol
	}{
		{"empty", nil, ProtoUnknown},
		{"empty slice", []byte{}, ProtoUnknown},
		{"GET request", []byte("GET / HTTP/1.1\r\n"), ProtoHTTP1},
		{"POST request", []byte("POST /api HTTP/1.1\r\n"), ProtoHTTP1},
		{"PUT request", []byte("PUT /resource HTTP/1.1\r\n"), ProtoHTTP1},
		{"DELETE request", []byte("DELETE /item HTTP/1.1\r\n"), ProtoHTTP1},
		{"HEAD request", []byte("HEAD / HTTP/1.1\r\n"), ProtoHTTP1},
		{"OPTIONS request", []byte("OPTIONS * HTTP/1.1\r\n"), ProtoHTTP1},
		{"PATCH request", []byte("PATCH /data HTTP/1.1\r\n"), ProtoHTTP1},
		{"CONNECT request", []byte("CONNECT host:443 HTTP/1.1\r\n"), ProtoHTTP1},
		{"TRACE request", []byte("TRACE / HTTP/1.1\r\n"), ProtoHTTP1},
		{"HTTP/2 preface", []byte("PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n"), ProtoHTTP2},
		{"HTTP/2 with frames", append([]byte("PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n"), []byte{0, 0, 0, 4, 0, 0, 0, 0, 0}...), ProtoHTTP2},
		{"partial H2 preface", []byte("PRI * HTTP"), ProtoHTTP2},
		{"garbage", []byte{0x15, 0x03, 0x01, 0x00}, ProtoUnknown},
		{"TLS record", []byte{0x16, 0x03, 0x01, 0x00, 0x80}, ProtoUnknown},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := Classify(tt.data)
			if got != tt.want {
				t.Errorf("Classify(%q) = %v, want %v", tt.data[:min(len(tt.data), 30)], got, tt.want)
			}
		})
	}
}

func TestClassify_PartialH2Preface(t *testing.T) {
	// A fragment that is a prefix of the H2 magic but shorter
	fragment := []byte("PRI * HTTP/2.0\r\n\r\nS")
	got := Classify(fragment)
	if got != ProtoHTTP2 {
		t.Errorf("Classify(partial H2 preface) = %v, want ProtoHTTP2", got)
	}
}

func TestMinInt(t *testing.T) {
	tests := []struct {
		a, b, want int
	}{
		{1, 2, 1},
		{5, 3, 3},
		{0, 0, 0},
		{-1, 1, -1},
	}
	for _, tt := range tests {
		got := minInt(tt.a, tt.b)
		if got != tt.want {
			t.Errorf("minInt(%d, %d) = %d, want %d", tt.a, tt.b, got, tt.want)
		}
	}
}