package gonexapp_test

import (
	"encoding/base64"
	"encoding/json"
	"io"
	"net/http"
	"net/http/httptest"
	"strings"
	"sync/atomic"
	"testing"
	"time"

	"gitea.neitzel.de/konrad/go-nc-exapp"
)

func authHeader(userID string) string {
	return base64.StdEncoding.EncodeToString([]byte(userID + ":secret"))
}

func okInner() http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
		w.WriteHeader(http.StatusOK)
		_, _ = io.WriteString(w, "ok")
	})
}

func TestAccessGateEmptyGroupsPassesThrough(t *testing.T) {
	gate := gonexapp.AccessGate{}
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)

	if rec.Code != http.StatusOK || rec.Body.String() != "ok" {
		t.Fatalf("got %d %q", rec.Code, rec.Body.String())
	}
}

func TestAccessGateSkipsLifecyclePaths(t *testing.T) {
	gate := gonexapp.AccessGate{Groups: []string{"dns-ops"}}
	h := gate.Wrap(okInner())

	for _, path := range []string{"/heartbeat", "/enabled", "/init"} {
		req := httptest.NewRequest(http.MethodGet, path, nil)
		rec := httptest.NewRecorder()
		h.ServeHTTP(rec, req)
		if rec.Code != http.StatusOK {
			t.Fatalf("%s: got %d", path, rec.Code)
		}
	}
}

func TestAccessGateExtraSkipPaths(t *testing.T) {
	gate := gonexapp.AccessGate{Groups: []string{"dns-ops"}, ExtraSkipPaths: []string{"/healthz"}}
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/healthz", nil)
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusOK {
		t.Fatalf("got %d", rec.Code)
	}
}

func TestAccessGateMissingUserUnauthorized(t *testing.T) {
	gate := gonexapp.AccessGate{Groups: []string{"dns-ops"}}
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusUnauthorized {
		t.Fatalf("got %d", rec.Code)
	}
}

func groupsOCSServer(t *testing.T, handler http.HandlerFunc) *httptest.Server {
	t.Helper()
	srv := httptest.NewServer(handler)
	t.Cleanup(srv.Close)
	return srv
}

func gateWithOCS(t *testing.T, groups []string, ttl time.Duration, srv *httptest.Server) gonexapp.AccessGate {
	t.Helper()
	cred := gonexapp.Credentials{
		BaseURL: srv.URL, AppID: "app", AppVersion: "0.1.0", AAVersion: "1.0.0", AppSecret: "s",
	}
	return gonexapp.AccessGate{
		Cred:     cred,
		Groups:   groups,
		CacheTTL: ttl,
		Client:   srv.Client(),
		OCS:      gonexapp.OCSClient{Cred: cred, Client: srv.Client()},
	}
}

func TestAccessGateAllowsAnyOfMember(t *testing.T) {
	var calls atomic.Int32
	srv := groupsOCSServer(t, func(w http.ResponseWriter, r *http.Request) {
		calls.Add(1)
		if r.Method != http.MethodGet || !strings.Contains(r.URL.Path, "/cloud/users/alice/groups") {
			http.Error(w, "bad path "+r.URL.Path, http.StatusBadRequest)
			return
		}
		_ = json.NewEncoder(w).Encode(map[string]any{
			"ocs": map[string]any{"data": map[string]any{"groups": []string{"other", "dns-ops"}}},
		})
	})
	gate := gateWithOCS(t, []string{"dns-ops", "dns-admins"}, 0, srv)
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	req.Header.Set("AUTHORIZATION-APP-API", authHeader("alice"))
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusOK || rec.Body.String() != "ok" {
		t.Fatalf("got %d %q", rec.Code, rec.Body.String())
	}
	if calls.Load() != 1 {
		t.Fatalf("ocs calls=%d", calls.Load())
	}
}

func TestAccessGateDeniesNonMemberWith403(t *testing.T) {
	srv := groupsOCSServer(t, func(w http.ResponseWriter, r *http.Request) {
		_ = json.NewEncoder(w).Encode(map[string]any{
			"ocs": map[string]any{"data": map[string]any{"groups": []string{"users"}}},
		})
	})
	gate := gateWithOCS(t, []string{"dns-ops"}, 0, srv)
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	req.Header.Set("AUTHORIZATION-APP-API", authHeader("alice"))
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusForbidden {
		t.Fatalf("got %d", rec.Code)
	}
	if strings.Contains(rec.Header().Get("Content-Type"), "text/html") {
		t.Fatalf("unexpected html content-type")
	}
}

func TestAccessGateDeniesNonMemberWithHTML(t *testing.T) {
	srv := groupsOCSServer(t, func(w http.ResponseWriter, r *http.Request) {
		_ = json.NewEncoder(w).Encode(map[string]any{
			"ocs": map[string]any{"data": map[string]any{"groups": []string{"users"}}},
		})
	})
	gate := gateWithOCS(t, []string{"dns-ops"}, 0, srv)
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("AUTHORIZATION-APP-API", authHeader("alice"))
	req.Header.Set("Accept", "text/html,application/xhtml+xml")
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusOK {
		t.Fatalf("got %d", rec.Code)
	}
	if !strings.Contains(rec.Header().Get("Content-Type"), "text/html") {
		t.Fatalf("content-type=%q", rec.Header().Get("Content-Type"))
	}
	if !strings.Contains(rec.Body.String(), "Access denied") {
		t.Fatalf("body=%q", rec.Body.String())
	}
	csp := rec.Header().Get("Content-Security-Policy")
	if !strings.Contains(csp, "frame-ancestors 'self'") {
		t.Fatalf("csp=%q", csp)
	}
}

func TestAccessGateSkipsTopMenuScriptPrefix(t *testing.T) {
	gate := gonexapp.AccessGate{Groups: []string{"dns-ops"}}
	h := gate.Wrap(okInner())

	for _, path := range []string{"/js/checkdns-main.js", "/js/app.js", "/js"} {
		req := httptest.NewRequest(http.MethodGet, path, nil)
		rec := httptest.NewRecorder()
		h.ServeHTTP(rec, req)
		if rec.Code != http.StatusOK || rec.Body.String() != "ok" {
			t.Fatalf("%s: got %d %q", path, rec.Code, rec.Body.String())
		}
	}

	req := httptest.NewRequest(http.MethodGet, "/json", nil)
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusUnauthorized {
		t.Fatalf("/json should stay gated, got %d", rec.Code)
	}
}

func TestAccessGateLookupFailureServiceUnavailable(t *testing.T) {
	srv := groupsOCSServer(t, func(w http.ResponseWriter, r *http.Request) {
		http.Error(w, "boom", http.StatusInternalServerError)
	})
	gate := gateWithOCS(t, []string{"dns-ops"}, 0, srv)
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	req.Header.Set("AUTHORIZATION-APP-API", authHeader("alice"))
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusServiceUnavailable {
		t.Fatalf("got %d", rec.Code)
	}
}

func TestAccessGateCachesPositiveMembership(t *testing.T) {
	var calls atomic.Int32
	srv := groupsOCSServer(t, func(w http.ResponseWriter, r *http.Request) {
		calls.Add(1)
		_ = json.NewEncoder(w).Encode(map[string]any{
			"ocs": map[string]any{"data": map[string]any{"groups": []string{"dns-ops"}}},
		})
	})
	now := time.Unix(1_700_000_000, 0)
	gate := gateWithOCS(t, []string{"dns-ops"}, time.Minute, srv)
	gate.Now = func() time.Time { return now }
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	req.Header.Set("AUTHORIZATION-APP-API", authHeader("alice"))
	for i := range 2 {
		rec := httptest.NewRecorder()
		h.ServeHTTP(rec, req)
		if rec.Code != http.StatusOK {
			t.Fatalf("pass %d: got %d", i, rec.Code)
		}
	}
	if calls.Load() != 1 {
		t.Fatalf("ocs calls=%d want 1", calls.Load())
	}
}

func TestAccessGateCacheKeyedByGroupSet(t *testing.T) {
	var calls atomic.Int32
	srv := groupsOCSServer(t, func(w http.ResponseWriter, r *http.Request) {
		calls.Add(1)
		_ = json.NewEncoder(w).Encode(map[string]any{
			"ocs": map[string]any{"data": map[string]any{"groups": []string{"dns-ops"}}},
		})
	})
	cred := gonexapp.Credentials{
		BaseURL: srv.URL, AppID: "app", AppVersion: "0.1.0", AAVersion: "1.0.0", AppSecret: "s",
	}
	gate := &gonexapp.AccessGate{
		Cred: cred, Groups: []string{"dns-ops"}, CacheTTL: time.Minute,
		Client: srv.Client(), OCS: gonexapp.OCSClient{Cred: cred, Client: srv.Client()},
	}
	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	req.Header.Set("AUTHORIZATION-APP-API", authHeader("alice"))
	if gate.Check(req) != gonexapp.CheckAllowed {
		t.Fatal("first allow")
	}
	gate.Groups = []string{"other-group"}
	if gate.Check(req) != gonexapp.CheckDenied {
		t.Fatalf("after group-set change want denied, calls=%d", calls.Load())
	}
	if calls.Load() != 2 {
		t.Fatalf("ocs calls=%d want 2 (cache must not reuse prior group-set)", calls.Load())
	}
}

func TestAccessGateDoesNotCacheDenial(t *testing.T) {
	var calls atomic.Int32
	srv := groupsOCSServer(t, func(w http.ResponseWriter, r *http.Request) {
		n := calls.Add(1)
		groups := []string{"users"}
		if n >= 2 {
			groups = []string{"dns-ops"}
		}
		_ = json.NewEncoder(w).Encode(map[string]any{
			"ocs": map[string]any{"data": map[string]any{"groups": groups}},
		})
	})
	gate := gateWithOCS(t, []string{"dns-ops"}, time.Minute, srv)
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	req.Header.Set("AUTHORIZATION-APP-API", authHeader("alice"))

	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusForbidden {
		t.Fatalf("first: got %d", rec.Code)
	}

	rec = httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusOK {
		t.Fatalf("second: got %d", rec.Code)
	}
	if calls.Load() != 2 {
		t.Fatalf("ocs calls=%d want 2", calls.Load())
	}
}

func TestAccessGateZeroTTLDisablesCache(t *testing.T) {
	var calls atomic.Int32
	srv := groupsOCSServer(t, func(w http.ResponseWriter, r *http.Request) {
		calls.Add(1)
		_ = json.NewEncoder(w).Encode(map[string]any{
			"ocs": map[string]any{"data": map[string]any{"groups": []string{"dns-ops"}}},
		})
	})
	gate := gateWithOCS(t, []string{"dns-ops"}, 0, srv)
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	req.Header.Set("AUTHORIZATION-APP-API", authHeader("alice"))
	for i := range 2 {
		rec := httptest.NewRecorder()
		h.ServeHTTP(rec, req)
		if rec.Code != http.StatusOK {
			t.Fatalf("pass %d: got %d", i, rec.Code)
		}
	}
	if calls.Load() != 2 {
		t.Fatalf("ocs calls=%d want 2", calls.Load())
	}
}

func TestAccessGateDoesNotCacheLookupErrors(t *testing.T) {
	var calls atomic.Int32
	srv := groupsOCSServer(t, func(w http.ResponseWriter, r *http.Request) {
		n := calls.Add(1)
		if n == 1 {
			http.Error(w, "boom", http.StatusInternalServerError)
			return
		}
		_ = json.NewEncoder(w).Encode(map[string]any{
			"ocs": map[string]any{"data": map[string]any{"groups": []string{"dns-ops"}}},
		})
	})
	gate := gateWithOCS(t, []string{"dns-ops"}, time.Minute, srv)
	h := gate.Wrap(okInner())

	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	req.Header.Set("AUTHORIZATION-APP-API", authHeader("alice"))

	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusServiceUnavailable {
		t.Fatalf("first: got %d", rec.Code)
	}

	rec = httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusOK {
		t.Fatalf("second: got %d", rec.Code)
	}
}

func TestParseRequiredGroups(t *testing.T) {
	got := gonexapp.ParseRequiredGroups(" dns-ops, dns-admins ,, ")
	if len(got) != 2 || got[0] != "dns-ops" || got[1] != "dns-admins" {
		t.Fatalf("got %#v", got)
	}
	if len(gonexapp.ParseRequiredGroups("")) != 0 {
		t.Fatalf("empty should be empty")
	}
}

func TestResolveRequiredGroups(t *testing.T) {
	def := []string{"checkdns"}
	if got := gonexapp.ResolveRequiredGroups("", false, def); len(got) != 1 || got[0] != "checkdns" {
		t.Fatalf("unset: %#v", got)
	}
	if got := gonexapp.ResolveRequiredGroups("", true, def); len(got) != 0 {
		t.Fatalf("set empty: %#v", got)
	}
	if got := gonexapp.ResolveRequiredGroups("ops", true, def); len(got) != 1 || got[0] != "ops" {
		t.Fatalf("set: %#v", got)
	}
}

func TestParseCacheSeconds(t *testing.T) {
	if d := gonexapp.ParseCacheSeconds("", 60); d != 60*time.Second {
		t.Fatalf("default unset: %v", d)
	}
	if d := gonexapp.ParseCacheSeconds("0", 60); d != 0 {
		t.Fatalf("zero: %v", d)
	}
	if d := gonexapp.ParseCacheSeconds("30", 60); d != 30*time.Second {
		t.Fatalf("thirty: %v", d)
	}
	if d := gonexapp.ParseCacheSeconds("nope", 60); d != 60*time.Second {
		t.Fatalf("invalid: %v", d)
	}
}

func TestAccessGateCheckStandalone(t *testing.T) {
	srv := groupsOCSServer(t, func(w http.ResponseWriter, r *http.Request) {
		_ = json.NewEncoder(w).Encode(map[string]any{
			"ocs": map[string]any{"data": map[string]any{"groups": []string{"dns-ops"}}},
		})
	})
	gate := gateWithOCS(t, []string{"dns-ops"}, 0, srv)
	ptr := &gonexapp.AccessGate{
		Cred: gate.Cred, Groups: gate.Groups, CacheTTL: gate.CacheTTL, Client: gate.Client, OCS: gate.OCS,
	}
	req := httptest.NewRequest(http.MethodGet, "/api/zones", nil)
	req.Header.Set("AUTHORIZATION-APP-API", authHeader("alice"))
	if got := ptr.Check(req); got != gonexapp.CheckAllowed {
		t.Fatalf("got %v", got)
	}
}