package dial_test

import (
	"context"
	"errors"
	"net/http"
	"net/http/httptest"
	"net/netip"
	"net/url"
	"strings"
	"sync/atomic"
	"testing"

	"git.wntrmute.dev/kyle/sift/internal/search/dial"
)

var errDNS = errors.New("dns down")

func TestLoopbackAllowsConfiguredPort(t *testing.T) {
	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(200)
		_, _ = w.Write([]byte("ok"))
	}))
	defer ts.Close()
	c, err := dial.New(ts.URL, dial.Options{Loopback: true, Timeout: 0})
	if err != nil {
		t.Fatal(err)
	}
	resp, err := c.HTTP.Get(ts.URL + "/")
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()
	if resp.StatusCode != 200 {
		t.Fatalf("status %d", resp.StatusCode)
	}
}

func TestLoopbackRefusesOtherPort(t *testing.T) {
	c, err := dial.New("http://127.0.0.1:8888", dial.Options{
		Loopback: true,
		Lookup: func(_ context.Context, _ string) ([]netip.Addr, error) {
			return []netip.Addr{netip.MustParseAddr("127.0.0.1")}, nil
		},
	})
	if err != nil {
		t.Fatal(err)
	}
	resp, err := c.HTTP.Get("http://127.0.0.1:11434/")
	if err == nil {
		resp.Body.Close()
		t.Fatal("dialed other loopback port")
	}
	if !strings.Contains(err.Error(), "refused") && !strings.Contains(err.Error(), "search dial") {
		t.Fatalf("err %v", err)
	}
}

func TestPublicPoisonedPrivateRefused(t *testing.T) {
	c, err := dial.New("https://api.tavily.com/search", dial.Options{
		Loopback: false,
		Lookup: func(_ context.Context, host string) ([]netip.Addr, error) {
			return []netip.Addr{netip.MustParseAddr("127.0.0.1")}, nil
		},
	})
	if err != nil {
		t.Fatal(err)
	}
	if c.Ready() {
		t.Fatal("poisoned A record pinned")
	}
}

func TestPublicPrivateRFC1918Refused(t *testing.T) {
	c, err := dial.New("https://api.search.brave.com/res/v1/llm/context", dial.Options{
		Lookup: func(_ context.Context, _ string) ([]netip.Addr, error) {
			return []netip.Addr{netip.MustParseAddr("10.0.0.5")}, nil
		},
	})
	if err != nil {
		t.Fatal(err)
	}
	if c.Ready() {
		t.Fatal("private A pinned")
	}
}

func TestTLSSystemRoots(t *testing.T) {
	c, err := dial.New("https://api.tavily.com/search", dial.Options{
		Lookup: func(_ context.Context, _ string) ([]netip.Addr, error) {
			return []netip.Addr{netip.MustParseAddr("1.1.1.1")}, nil
		},
	})
	if err != nil {
		t.Fatal(err)
	}
	cfg := c.TLSConfig()
	if cfg == nil {
		t.Fatal("nil tls")
	}
	if cfg.InsecureSkipVerify {
		t.Fatal("InsecureSkipVerify")
	}
	if cfg.RootCAs != nil {
		t.Fatal("want system roots (nil RootCAs)")
	}
}

func TestNoUserinfo(t *testing.T) {
	_, err := dial.New("http://u:p@127.0.0.1:8888", dial.Options{Loopback: true})
	if err == nil {
		t.Fatal("userinfo allowed")
	}
}

func TestParseRejectsNonHTTP(t *testing.T) {
	_, err := dial.New("ftp://example.com/", dial.Options{})
	if err == nil {
		t.Fatal("ftp allowed")
	}
	_ = url.URL{}
}

func TestResolveRetriesAfterDNSDown(t *testing.T) {
	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(200)
	}))
	defer ts.Close()
	u, _ := url.Parse(ts.URL)
	ip := netip.MustParseAddr(u.Hostname())
	var n atomic.Int32
	c, err := dial.New(ts.URL, dial.Options{
		Loopback: true,
		Lookup: func(_ context.Context, host string) ([]netip.Addr, error) {
			if n.Add(1) == 1 {
				return nil, errDNS
			}
			return []netip.Addr{ip}, nil
		},
	})
	if err != nil {
		t.Fatal(err)
	}
	if c.Ready() {
		t.Fatal("first lookup should fail")
	}
	if err := c.Ensure(context.Background()); err != nil {
		t.Fatal(err)
	}
	if !c.Ready() {
		t.Fatal("retry")
	}
	resp, err := c.HTTP.Get(ts.URL + "/")
	if err != nil {
		t.Fatal(err)
	}
	resp.Body.Close()
}