package mock

import (
	"context"
	"path/filepath"
	"testing"
	"time"

	"tera-clone/services/tera-api/internal/domain"
	"tera-clone/services/tera-api/internal/externalauth"
)

type dualExternalAuthenticator struct{}

func (dualExternalAuthenticator) Authenticate(_ context.Context, method string, server externalauth.Server, username, password string, _ time.Duration) (bool, error) {
	return (method == "radius" || method == "tacacs") && server.Secret == method+"-test-secret" && username == "remote-user" && password == "remote-password", nil
}

func newExternalSecretTestStore(t *testing.T) (*Store, StoreOptions) {
	t.Helper()
	directory := t.TempDir()
	options := StoreOptions{
		ConfigPath: filepath.Join(directory, "config.json"), SecretPath: filepath.Join(directory, "secrets.json"),
		ExternalAuthenticator: dualExternalAuthenticator{},
	}
	store, err := NewStoreWithOptions(fixedClock, options)
	if err != nil {
		t.Fatal(err)
	}
	enabled, fallback, method, role := true, true, "radius", "port_operator"
	_, err = store.UpdateExternalAuth(context.Background(), domain.ExternalAuthUpdate{
		Enabled: &enabled, PrimaryMethod: &method, LocalFallback: &fallback, DefaultRole: &role,
		RadiusServers: []domain.ExternalAuthServer{{ServerID: "radius-primary", Host: "radius.local", Port: 1645, Secret: "radius-test-secret", Enabled: true}},
		TACACSServers: []domain.ExternalAuthServer{{ServerID: "tacacs-primary", Host: "tacacs.local", Port: 49, Secret: "tacacs-test-secret", Enabled: true}},
	})
	if err != nil {
		t.Fatal(err)
	}
	if _, err := store.SaveAndApplyConfig(context.Background()); err != nil {
		t.Fatal(err)
	}
	return store, options
}

func assertExternalTestSecrets(t *testing.T, store *Store, radius, tacacs string) {
	t.Helper()
	for method, expected := range map[string]string{"radius": radius, "tacacs": tacacs} {
		for _, phase := range []string{"running", "persistent"} {
			key := externalAuthSecretKey(phase, method, method+"-primary")
			value, exists := store.secrets.Get(key)
			if expected == "" {
				if exists {
					t.Errorf("cleared key %s was resurrected", key)
				}
			} else if !exists || string(value) != expected {
				t.Errorf("key %s was not preserved", key)
			}
		}
	}
}

func TestExternalAuthPolicyOnlyUpdatesPreserveBothSecrets(t *testing.T) {
	for _, workflow := range []string{"apply-save", "save-apply", "save-and-apply"} {
		t.Run(workflow, func(t *testing.T) {
			store, options := newExternalSecretTestStore(t)
			for _, method := range []string{"tacacs", "radius", "tacacs", "radius"} {
				if _, err := store.UpdateExternalAuth(context.Background(), domain.ExternalAuthUpdate{PrimaryMethod: &method}); err != nil {
					t.Fatal(err)
				}
				role := "administrator"
				if _, err := store.UpdateExternalAuth(context.Background(), domain.ExternalAuthUpdate{DefaultRole: &role}); err != nil {
					t.Fatal(err)
				}
				var err error
				switch workflow {
				case "apply-save":
					_, err = store.ApplyConfig(context.Background())
					if err == nil {
						_, err = store.SaveConfig(context.Background())
					}
				case "save-apply":
					_, err = store.SaveConfig(context.Background())
					if err == nil {
						_, err = store.ApplyConfig(context.Background())
					}
				case "save-and-apply":
					_, err = store.SaveAndApplyConfig(context.Background())
				}
				if err != nil {
					t.Fatal(err)
				}
				assertExternalTestSecrets(t, store, "radius-test-secret", "tacacs-test-secret")
				// Also verify persisted state after reopening the store.
				store, err = NewStoreWithOptions(fixedClock, options)
				if err != nil {
					t.Fatal(err)
				}
				assertExternalTestSecrets(t, store, "radius-test-secret", "tacacs-test-secret")
				session, err := store.Login(context.Background(), domain.AuthLoginRequest{Username: "remote-user", Password: "remote-password"})
				if err != nil || session.Actor != "external-remote-user" || session.Role != role {
					t.Fatalf("external %s login failed after policy update: %v", method, err)
				}
			}
		})
	}
}

func TestExternalAuthSingleProviderUpdatePreservesOtherSecret(t *testing.T) {
	for _, method := range []string{"radius", "tacacs"} {
		t.Run(method, func(t *testing.T) {
			store, _ := newExternalSecretTestStore(t)
			servers := []domain.ExternalAuthServer{{ServerID: method + "-primary", Host: method + ".local", Port: 49, Enabled: true}}
			update := domain.ExternalAuthUpdate{}
			if method == "radius" {
				servers[0].Port = 1645
				update.RadiusServers = servers
			} else {
				update.TACACSServers = servers
			}
			if _, err := store.UpdateExternalAuth(context.Background(), update); err != nil {
				t.Fatal(err)
			}
			if _, err := store.SaveAndApplyConfig(context.Background()); err != nil {
				t.Fatal(err)
			}
			assertExternalTestSecrets(t, store, "radius-test-secret", "tacacs-test-secret")
		})
	}
}

func TestExternalAuthExplicitClearSurvivesPolicyUpdate(t *testing.T) {
	store, _ := newExternalSecretTestStore(t)
	_, err := store.UpdateExternalAuth(context.Background(), domain.ExternalAuthUpdate{
		TACACSServers: []domain.ExternalAuthServer{{ServerID: "tacacs-primary", Host: "tacacs.local", Port: 49, Enabled: false, ClearSecret: true}},
	})
	if err != nil {
		t.Fatal(err)
	}
	role := "administrator"
	if _, err := store.UpdateExternalAuth(context.Background(), domain.ExternalAuthUpdate{DefaultRole: &role}); err != nil {
		t.Fatal(err)
	}
	if _, err := store.SaveAndApplyConfig(context.Background()); err != nil {
		t.Fatal(err)
	}
	assertExternalTestSecrets(t, store, "radius-test-secret", "")
}

func TestExternalAuthMissingSourceCannotEraseStoredSecret(t *testing.T) {
	store, _ := newExternalSecretTestStore(t)
	// Simulate a pending transaction written by the old implementation, which
	// omitted unchanged secrets from the pending namespace.
	store.pendingExternalAuth = cloneExternalAuthPointer(store.runningExternalAuth)
	store.pendingExternalAuth.PrimaryMethod = "tacacs"
	if _, err := store.ApplyConfig(context.Background()); err == nil {
		t.Fatal("applying missing source secrets should fail instead of deleting destination secrets")
	}
	assertExternalTestSecrets(t, store, "radius-test-secret", "tacacs-test-secret")
}

func TestExternalAuthReportsMissingProtectedSecretAndRejectsPolicyOnlyUpdate(t *testing.T) {
	store, _ := newExternalSecretTestStore(t)
	for _, phase := range []string{"running", "persistent"} {
		if err := store.secrets.Delete(externalAuthSecretKey(phase, "radius", "radius-primary")); err != nil {
			t.Fatal(err)
		}
	}
	settings, err := store.ExternalAuth(context.Background())
	if err != nil {
		t.Fatal(err)
	}
	if settings.RadiusServers[0].SecretStored || !settings.TACACSServers[0].SecretStored {
		t.Fatal("secret availability must reflect the protected store, not stale configuration markers")
	}
	role := "administrator"
	if _, err := store.UpdateExternalAuth(context.Background(), domain.ExternalAuthUpdate{DefaultRole: &role}); err == nil {
		t.Fatal("a policy-only update with a missing protected secret must fail")
	}
	assertExternalTestSecrets(t, store, "", "tacacs-test-secret")
}