package main

import (
	"crypto/sha256"
	"net/http"
	"net/http/httptest"
	"net/url"
	"testing"
)

func TestProxyForwardsResponseAndStripsClientIPHeaders(t *testing.T) {
	upstream := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if got := r.Header.Get("X-Forwarded-For"); got != "" {
			t.Fatalf("forwarded client IP header leaked: %q", got)
		}
		w.Header().Set("Subscription-Userinfo", "upload=1; download=2; total=3")
		w.Header().Add("Set-Cookie", "a=b")
		w.WriteHeader(http.StatusAccepted)
		_, _ = w.Write([]byte("raw-subscription"))
	}))
	defer upstream.Close()

	p := &proxy{
		tokenHash: sha256ForTest("secret"),
		client:    upstream.Client(),
	}

	req := httptest.NewRequest(http.MethodGet, "/secret?url="+url.QueryEscape(upstream.URL+"/sub?token=abc"), nil)
	req.Header.Set("X-Forwarded-For", "1.2.3.4")
	rec := httptest.NewRecorder()

	p.ServeHTTP(rec, req)

	if rec.Code != http.StatusAccepted {
		t.Fatalf("status = %d", rec.Code)
	}
	if got := rec.Body.String(); got != "raw-subscription" {
		t.Fatalf("body = %q", got)
	}
	if got := rec.Header().Get("Subscription-Userinfo"); got == "" {
		t.Fatal("missing upstream response header")
	}
	if got := rec.Header().Values("Set-Cookie"); len(got) != 1 || got[0] != "a=b" {
		t.Fatalf("set-cookie = %#v", got)
	}
}

func TestRejectsBadToken(t *testing.T) {
	p := &proxy{tokenHash: sha256ForTest("secret")}
	req := httptest.NewRequest(http.MethodGet, "/bad?url=https://example.com", nil)
	rec := httptest.NewRecorder()

	p.ServeHTTP(rec, req)

	if rec.Code != http.StatusNotFound {
		t.Fatalf("status = %d", rec.Code)
	}
}

func sha256ForTest(s string) [32]byte {
	return sha256.Sum256([]byte(s))
}