package httpx_test

import (
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"git.yuntuo.hk/k2safe/go-omni/httpx"
)

func TestClientIPResolverUsesSocketPeerByDefault(t *testing.T) {
	resolver, err := httpx.NewClientIPResolver()
	if err != nil {
		t.Fatal(err)
	}
	request := newClientIPRequest("192.0.2.10:443", "198.51.100.7")
	if got := resolver.ClientIP(request); got != "192.0.2.10" {
		t.Fatalf("untrusted forwarding header changed client IP: %q", got)
	}
}

func TestClientIPResolverWalksTrustedForwardingChain(t *testing.T) {
	resolver, err := httpx.NewClientIPResolver("10.0.0.0/8")
	if err != nil {
		t.Fatal(err)
	}
	request := newClientIPRequest("10.0.0.5:443", "198.51.100.7, 10.0.0.4")
	if got := resolver.ClientIP(request); got != "198.51.100.7" {
		t.Fatalf("expected original client IP, got %q", got)
	}

	request = newClientIPRequest("10.0.0.5:443", "198.51.100.7, 203.0.113.9, 10.0.0.4")
	if got := resolver.ClientIP(request); got != "203.0.113.9" {
		t.Fatalf("expected first untrusted hop, got %q", got)
	}
}

func TestClientIPResolverRejectsMalformedForwardingData(t *testing.T) {
	resolver, err := httpx.NewClientIPResolver("127.0.0.1")
	if err != nil {
		t.Fatal(err)
	}
	request := newClientIPRequest("127.0.0.1:443", "198.51.100.7, not-an-ip")
	if got := resolver.ClientIP(request); got != "127.0.0.1" {
		t.Fatalf("malformed forwarding header should fall back to peer, got %q", got)
	}
}

func TestNewClientIPResolverRejectsHostnames(t *testing.T) {
	if _, err := httpx.NewClientIPResolver("proxy.example.com"); err == nil || !strings.Contains(err.Error(), "invalid trusted proxy") {
		t.Fatalf("expected hostname validation error, got %v", err)
	}
}

func TestContextClientIPUsesResolverFromRequestContext(t *testing.T) {
	resolver, err := httpx.NewClientIPResolver("127.0.0.1")
	if err != nil {
		t.Fatal(err)
	}
	request := newClientIPRequest("127.0.0.1:443", "198.51.100.7")
	request = request.WithContext(httpx.WithClientIPResolver(request.Context(), resolver))
	ctx := httpx.NewContext(request, httptest.NewRecorder(), nil)
	if got := ctx.ClientIP(); got != "198.51.100.7" {
		t.Fatalf("expected context client IP, got %q", got)
	}
}

func newClientIPRequest(remote, forwarded string) *http.Request {
	request := httptest.NewRequest(http.MethodGet, "http://example.test/", nil)
	request.RemoteAddr = remote
	if forwarded != "" {
		request.Header.Set("X-Forwarded-For", forwarded)
	}
	return request
}