package adminapi_test

import (
	"bytes"
	"encoding/json"
	"io"
	"log/slog"
	"net/http"
	"net/http/httptest"
	"path/filepath"
	"testing"

	"github.com/dariuszjaniak/warp/server/internal/adminapi"
	"github.com/dariuszjaniak/warp/server/internal/federation"
	"github.com/dariuszjaniak/warp/server/internal/httputil"
	"github.com/dariuszjaniak/warp/server/internal/settings"
	"github.com/dariuszjaniak/warp/server/internal/storage"
	_ "github.com/dariuszjaniak/warp/server/internal/storage/drivers"
	"github.com/dariuszjaniak/warp/server/internal/userapi"
)

const testServerName = "warp.example"

// testServer is an admin API on a throwaway SQLite database.
type testServer struct {
	t        *testing.T
	handler  http.Handler
	users    *userapi.API
	settings *settings.Service
}

// newTestServer builds the component. defaults are the config-file values
// the settings service starts from, which is how a test pins a switch.
func newTestServer(t *testing.T, defaults settings.Defaults) *testServer {
	t.Helper()

	path := filepath.ToSlash(filepath.Join(t.TempDir(), "warp.db"))
	db, err := storage.Open(t.Context(), storage.Config{
		Driver:           storage.DriverSQLite,
		ConnectionString: "file:" + path,
	}, slog.New(slog.DiscardHandler))
	if err != nil {
		t.Fatalf("open storage: %v", err)
	}
	t.Cleanup(func() { _ = db.Close() })
	if err := db.Migrate(t.Context()); err != nil {
		t.Fatalf("migrate: %v", err)
	}

	users, err := userapi.New(userapi.Options{
		ServerName: testServerName,
		Store:      db.Users(),
		Logger:     slog.New(slog.DiscardHandler),
	})
	if err != nil {
		t.Fatalf("userapi.New: %v", err)
	}

	settingsService, err := settings.New(t.Context(), db.Settings(), defaults, slog.New(slog.DiscardHandler))
	if err != nil {
		t.Fatalf("settings.New: %v", err)
	}

	api, err := adminapi.New(adminapi.Options{
		ServerName: testServerName,
		Users:      users,
		Settings:   settingsService,
		Federation: federation.NewGate(settingsService.FederationEnabled,
			federation.NewPolicy([]string{"friend.example"}, []string{"spam.example"})),
		Database: db,
		Logger:   slog.New(slog.DiscardHandler),
	})
	if err != nil {
		t.Fatalf("adminapi.New: %v", err)
	}

	router := httputil.NewRouter(nil)
	api.RegisterRoutes(router)
	return &testServer{t: t, handler: router, users: users, settings: settingsService}
}

func (ts *testServer) do(method, path, token string, body any) *httptest.ResponseRecorder {
	ts.t.Helper()

	var reader io.Reader
	if body != nil {
		raw, err := json.Marshal(body)
		if err != nil {
			ts.t.Fatal(err)
		}
		reader = bytes.NewReader(raw)
	}
	req := httptest.NewRequest(method, path, reader)
	if token != "" {
		req.Header.Set("Authorization", "Bearer "+token)
	}
	rec := httptest.NewRecorder()
	ts.handler.ServeHTTP(rec, req)
	return rec
}

// admin creates an administrator and returns its access token.
func (ts *testServer) admin(localpart string) string {
	ts.t.Helper()
	return ts.account(localpart, true)
}

// user creates an ordinary account and returns its access token.
func (ts *testServer) user(localpart string) string {
	ts.t.Helper()
	return ts.account(localpart, false)
}

func (ts *testServer) account(localpart string, admin bool) string {
	ts.t.Helper()
	if _, err := ts.users.CreateAccount(ts.t.Context(), userapi.NewAccountRequest{
		Localpart: localpart,
		Password:  "sUp3rs3kr1t",
		Admin:     admin,
	}); err != nil {
		ts.t.Fatalf("CreateAccount: %v", err)
	}
	session, err := ts.users.CreateSession(ts.t.Context(), userapi.SessionRequest{Localpart: localpart})
	if err != nil {
		ts.t.Fatalf("CreateSession: %v", err)
	}
	return session.AccessToken
}

func jsonBody(t *testing.T, rec *httptest.ResponseRecorder) map[string]any {
	t.Helper()
	var out map[string]any
	if err := json.Unmarshal(rec.Body.Bytes(), &out); err != nil {
		t.Fatalf("response is not JSON (%s): %v", rec.Body.String(), err)
	}
	return out
}

func expectStatus(t *testing.T, rec *httptest.ResponseRecorder, want int) {
	t.Helper()
	if rec.Code != want {
		t.Fatalf("status = %d, want %d (body: %s)", rec.Code, want, rec.Body.String())
	}
}

func expectError(t *testing.T, rec *httptest.ResponseRecorder, status int, errcode string) {
	t.Helper()
	expectStatus(t, rec, status)
	if got := jsonBody(t, rec)["errcode"]; got != errcode {
		t.Errorf("errcode = %v, want %s (body: %s)", got, errcode, rec.Body.String())
	}
}

const (
	federationPath   = adminapi.Prefix + "/federation"
	registrationPath = adminapi.Prefix + "/registration"
	usersPath        = adminapi.Prefix + "/users"
	statsPath        = adminapi.Prefix + "/stats"
)

var toggleable = settings.Defaults{
	FederationAllowRuntimeToggle:   true,
	RegistrationAllowRuntimeToggle: true,
}

// TestAdminAuth is the gate everything else here depends on.
func TestAdminAuth(t *testing.T) {
	ts := newTestServer(t, toggleable)
	admin := ts.admin("root")
	ordinary := ts.user("alice")

	for name, tc := range map[string]struct {
		token  string
		status int
		code   string
	}{
		"no token":      {"", http.StatusUnauthorized, "M_MISSING_TOKEN"},
		"unknown token": {"not-a-token", http.StatusUnauthorized, "M_UNKNOWN_TOKEN"},
		"ordinary user": {ordinary, http.StatusForbidden, "M_FORBIDDEN"},
	} {
		t.Run(name, func(t *testing.T) {
			expectError(t, ts.do(http.MethodGet, statsPath, tc.token, nil), tc.status, tc.code)
		})
	}

	expectStatus(t, ts.do(http.MethodGet, statsPath, admin, nil), http.StatusOK)
}

// TestAdminTokenNotAcceptedInQueryString: an admin token in a URL ends up in
// every access log between here and the browser.
func TestAdminTokenNotAcceptedInQueryString(t *testing.T) {
	ts := newTestServer(t, toggleable)
	admin := ts.admin("root")

	expectError(t, ts.do(http.MethodGet, statsPath+"?access_token="+admin, "", nil),
		http.StatusUnauthorized, "M_MISSING_TOKEN")
}

// TestFederationSwitch is the admin half of PLAN.md section 3: the switch
// flips at runtime and the gate follows.
func TestFederationSwitch(t *testing.T) {
	ts := newTestServer(t, toggleable)
	admin := ts.admin("root")

	rec := ts.do(http.MethodGet, federationPath, admin, nil)
	expectStatus(t, rec, http.StatusOK)
	body := jsonBody(t, rec)
	if body["enabled"] != false {
		t.Errorf("federation should start disabled, got %v", body["enabled"])
	}
	if body["toggleable"] != true {
		t.Errorf("toggleable = %v, want true", body["toggleable"])
	}
	// The dashboard needs to show which servers a running Warp will talk
	// to, even though editing the lists is Phase 9.
	if allowlist, _ := body["allowlist"].([]any); len(allowlist) != 1 || allowlist[0] != "friend.example" {
		t.Errorf("allowlist = %v", body["allowlist"])
	}
	if denylist, _ := body["denylist"].([]any); len(denylist) != 1 || denylist[0] != "spam.example" {
		t.Errorf("denylist = %v", body["denylist"])
	}

	rec = ts.do(http.MethodPut, federationPath, admin, map[string]any{"enabled": true})
	expectStatus(t, rec, http.StatusOK)
	if jsonBody(t, rec)["enabled"] != true {
		t.Errorf("the PUT should report the new state, got %s", rec.Body.String())
	}
	if !ts.settings.FederationEnabled() {
		t.Error("the settings service did not pick the change up")
	}

	rec = ts.do(http.MethodPut, federationPath, admin, map[string]any{"enabled": false})
	expectStatus(t, rec, http.StatusOK)
	if ts.settings.FederationEnabled() {
		t.Error("switching back off did not take effect")
	}
}

func TestRegistrationSwitch(t *testing.T) {
	ts := newTestServer(t, toggleable)
	admin := ts.admin("root")

	rec := ts.do(http.MethodPut, registrationPath, admin, map[string]any{"enabled": true})
	expectStatus(t, rec, http.StatusOK)
	if !ts.settings.RegistrationEnabled() {
		t.Error("registration was not enabled")
	}

	rec = ts.do(http.MethodGet, registrationPath, admin, nil)
	expectStatus(t, rec, http.StatusOK)
	if jsonBody(t, rec)["enabled"] != true {
		t.Errorf("GET = %s", rec.Body.String())
	}
}

// TestSwitchPinnedByConfig covers settings.ErrNotToggleable: the request was
// fine, the server's own configuration is what refuses it, so it is a
// conflict rather than a bad request.
func TestSwitchPinnedByConfig(t *testing.T) {
	ts := newTestServer(t, settings.Defaults{})
	admin := ts.admin("root")

	for _, path := range []string{federationPath, registrationPath} {
		rec := ts.do(http.MethodPut, path, admin, map[string]any{"enabled": true})
		expectError(t, rec, http.StatusConflict, "M_FORBIDDEN")
		if msg, _ := jsonBody(t, rec)["error"].(string); msg == "" {
			t.Error("the refusal must say which setting is pinned")
		}

		// And the GET says so in advance, so the panel can grey the
		// switch out instead of offering something that will bounce.
		rec = ts.do(http.MethodGet, path, admin, nil)
		expectStatus(t, rec, http.StatusOK)
		if jsonBody(t, rec)["toggleable"] != false {
			t.Errorf("GET %s reports toggleable, but it is pinned", path)
		}
	}
}

func TestSwitchRequiresTheEnabledField(t *testing.T) {
	ts := newTestServer(t, toggleable)
	admin := ts.admin("root")

	expectError(t, ts.do(http.MethodPut, federationPath, admin, map[string]any{}),
		http.StatusBadRequest, "M_MISSING_PARAM")
}

func TestListUsers(t *testing.T) {
	ts := newTestServer(t, toggleable)
	admin := ts.admin("root")
	ts.user("alice")
	ts.user("bob")

	rec := ts.do(http.MethodGet, usersPath, admin, nil)
	expectStatus(t, rec, http.StatusOK)

	body := jsonBody(t, rec)
	if total, _ := body["total"].(float64); total != 3 {
		t.Errorf("total = %v, want 3", body["total"])
	}
	users, _ := body["users"].([]any)
	if len(users) != 3 {
		t.Fatalf("got %d users, want 3", len(users))
	}
	first, _ := users[0].(map[string]any)
	if first["user_id"] != "@alice:warp.example" {
		t.Errorf("users are not ordered by localpart: %s", rec.Body.String())
	}
	if first["admin"] != false {
		t.Errorf("alice should not be an admin: %v", first)
	}

	// Paging reports the full total so the panel can show how many pages
	// there are.
	rec = ts.do(http.MethodGet, usersPath+"?limit=1&offset=1", admin, nil)
	expectStatus(t, rec, http.StatusOK)
	body = jsonBody(t, rec)
	users, _ = body["users"].([]any)
	if len(users) != 1 || users[0].(map[string]any)["user_id"] != "@bob:warp.example" {
		t.Errorf("paged listing = %s", rec.Body.String())
	}
	if total, _ := body["total"].(float64); total != 3 {
		t.Errorf("paged total = %v, want 3", body["total"])
	}

	rec = ts.do(http.MethodGet, usersPath+"?search=ali", admin, nil)
	expectStatus(t, rec, http.StatusOK)
	if total, _ := jsonBody(t, rec)["total"].(float64); total != 1 {
		t.Errorf("search found %v users, want 1", jsonBody(t, rec)["total"])
	}

	expectError(t, ts.do(http.MethodGet, usersPath+"?limit=lots", admin, nil),
		http.StatusBadRequest, "M_INVALID_PARAM")
	expectError(t, ts.do(http.MethodGet, usersPath+"?offset=-1", admin, nil),
		http.StatusBadRequest, "M_INVALID_PARAM")
}

// TestCreateUser covers the way an operator adds an account to a server with
// registration switched off — which is the normal state of a private Warp.
func TestCreateUser(t *testing.T) {
	ts := newTestServer(t, toggleable)
	admin := ts.admin("root")

	if ts.settings.RegistrationEnabled() {
		t.Fatal("this test needs registration to be off")
	}

	rec := ts.do(http.MethodPost, usersPath, admin, map[string]any{
		"username":     "Alice",
		"password":     "sUp3rs3kr1t",
		"display_name": "Alice",
		"admin":        true,
	})
	expectStatus(t, rec, http.StatusCreated)

	body := jsonBody(t, rec)
	if body["user_id"] != "@alice:warp.example" {
		t.Errorf("user_id = %v; the localpart should be normalised", body["user_id"])
	}
	if body["admin"] != true {
		t.Errorf("admin = %v, want true", body["admin"])
	}

	// The new account can really log in, which is the only thing that
	// makes creating it useful.
	if err := ts.users.CheckPassword(t.Context(), "alice", "sUp3rs3kr1t"); err != nil {
		t.Errorf("the created account cannot log in: %v", err)
	}

	expectError(t, ts.do(http.MethodPost, usersPath, admin, map[string]any{
		"username": "alice", "password": "sUp3rs3kr1t",
	}), http.StatusBadRequest, "M_USER_IN_USE")

	expectError(t, ts.do(http.MethodPost, usersPath, admin, map[string]any{
		"username": "not valid", "password": "sUp3rs3kr1t",
	}), http.StatusBadRequest, "M_INVALID_USERNAME")

	expectError(t, ts.do(http.MethodPost, usersPath, admin, map[string]any{"username": "bob"}),
		http.StatusBadRequest, "M_MISSING_PARAM")
	expectError(t, ts.do(http.MethodPost, usersPath, admin, map[string]any{"password": "x"}),
		http.StatusBadRequest, "M_MISSING_PARAM")
}

func TestStats(t *testing.T) {
	ts := newTestServer(t, toggleable)
	admin := ts.admin("root")
	ts.user("alice")

	rec := ts.do(http.MethodGet, statsPath, admin, nil)
	expectStatus(t, rec, http.StatusOK)

	body := jsonBody(t, rec)
	if body["server_name"] != testServerName {
		t.Errorf("server_name = %v", body["server_name"])
	}
	if body["database"] != storage.DriverSQLite {
		t.Errorf("database = %v, want sqlite", body["database"])
	}
	if users, _ := body["users"].(float64); users != 2 {
		t.Errorf("users = %v, want 2", body["users"])
	}
	if admins, _ := body["admins"].(float64); admins != 1 {
		t.Errorf("admins = %v, want 1", body["admins"])
	}
	// Each account above got one session, so the device count follows.
	if devices, _ := body["devices"].(float64); devices != 2 {
		t.Errorf("devices = %v, want 2", body["devices"])
	}
	if body["federation_enabled"] != false || body["registration_enabled"] != false {
		t.Errorf("switch state = %s", rec.Body.String())
	}
}