package bm

import (
	"context"
	"errors"
	"net/http"
	"net/http/httptest"
	"testing"

	"git.golem15.com/golem15/summercms/modules/backpack"
	"git.golem15.com/golem15/summercms/modules/bouncer"
	"git.golem15.com/golem15/summercms/modules/compass"
	"git.golem15.com/golem15/summercms/modules/pact"
	"git.golem15.com/golem15/summercms/modules/party"
	"git.golem15.com/golem15/summercms/modules/wire"
	"gorm.io/gorm"
)

// fakePresentations stands in for golem15.presentations: its owner guard
// lets user 5 through and refuses everyone else.
type fakePresentations struct{}

func (fakePresentations) ID() string                   { return "golem15.presentations" }
func (fakePresentations) Requires() []string           { return nil }
func (fakePresentations) Register(*backpack.App) error { return nil }
func (fakePresentations) Boot(*backpack.App) error     { return nil }
func (fakePresentations) Middlewares() map[string]pact.Middleware {
	return map[string]pact.Middleware{
		"presentations.realtime-owner": func(next http.Handler) http.Handler {
			return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				if u, ok := bouncer.User(r.Context()); !ok || u.ID != 5 {
					w.Header().Set("Cache-Control", "no-cache, private")
					wire.WriteJSON(w, http.StatusForbidden, map[string]string{"error": "Forbidden"})
					return
				}
				next.ServeHTTP(w, r)
			})
		},
	}
}

// chatGroupMember is the injected group check: user 7 is in the chat
// group, user 13 makes the check fail.
func chatGroupMember(_ context.Context, _ *gorm.DB, userID uint, group string) (bool, error) {
	if userID == 13 {
		return false, errors.New("database down")
	}
	return group == "studenci" && userID == 7, nil
}

// accessPlugin builds jz.bm on an app with the given active plugin ids, a
// published (fake) database unless noDB, and golem15.presentations in the
// activated list when withOwnerGuard.
func accessPlugin(t *testing.T, ids []string, noDB, withOwnerGuard bool) *Plugin {
	t.Helper()
	cfg, err := compass.Open(compass.Options{Dir: t.TempDir(), Environ: []string{"SUMMER_ENV=testing"}})
	if err != nil {
		t.Fatal(err)
	}
	app := backpack.New(cfg)
	app.SetPlugins(ids)
	if !noDB {
		if err := app.Publish[*gorm.DB](&gorm.DB{}); err != nil {
			t.Fatal(err)
		}
	}
	activated := party.Activated{}
	if withOwnerGuard {
		activated = append(activated, fakePresentations{})
	}
	if err := app.Publish(activated); err != nil {
		t.Fatal(err)
	}
	return &Plugin{app: app, chatMember: chatGroupMember}
}

func TestRealtimeAccess(t *testing.T) {
	chatOnly := []string{"golem15.user", "golem15.chat", "jz.bm"}
	both := []string{"golem15.user", "golem15.chat", "jz.bm", "golem15.presentations"}
	presOnly := []string{"golem15.user", "jz.bm", "golem15.presentations"}
	for _, c := range []struct {
		name        string
		ids         []string
		noDB, guard bool
		userID      uint
		want        int
	}{
		{"no user", both, false, true, 0, http.StatusUnauthorized},
		{"chat member", chatOnly, false, false, 7, http.StatusOK},
		{"chat member with presentations", both, false, true, 7, http.StatusOK},
		{"non-member without presentations", chatOnly, false, false, 8, http.StatusForbidden},
		{"presentation owner", both, false, true, 5, http.StatusOK},
		{"presentation owner without chat", presOnly, false, true, 5, http.StatusOK},
		{"neither member nor owner", both, false, true, 8, http.StatusForbidden},
		{"presentations guard not found", both, false, false, 5, http.StatusForbidden},
		{"no database", both, true, true, 7, http.StatusServiceUnavailable},
		{"membership check fails", both, false, true, 13, http.StatusServiceUnavailable},
		{"no consumer", []string{"golem15.user", "jz.bm"}, false, false, 7, http.StatusForbidden},
	} {
		p := accessPlugin(t, c.ids, c.noDB, c.guard)
		mw, ok := p.Middlewares()[MiddlewareRealtimeAccess]
		if !ok {
			t.Fatalf("%s is not exported", MiddlewareRealtimeAccess)
		}
		h := mw(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) { w.WriteHeader(http.StatusOK) }))
		req := httptest.NewRequest(http.MethodGet, "/api/realtime/token", nil)
		if c.userID != 0 {
			req = req.WithContext(bouncer.WithUser(req.Context(), &bouncer.Principal{ID: c.userID}))
		}
		rec := httptest.NewRecorder()
		h.ServeHTTP(rec, req)
		if rec.Code != c.want {
			t.Errorf("%s: %d %s, want %d", c.name, rec.Code, rec.Body.String(), c.want)
			continue
		}
		if c.want != http.StatusOK {
			if got := rec.Header().Get("Cache-Control"); got != "no-cache, private" {
				t.Errorf("%s: Cache-Control %q, want no-cache, private", c.name, got)
			}
			if body := rec.Body.String(); body == "" || body[0] != '{' {
				t.Errorf("%s: body %q is not an error object", c.name, body)
			}
		}
	}
}