void OnCommand()

in Tools/msi/bundle/bootstrap/PythonBootstrapperApplication.cpp [262:436]
140 lines of code
38 McCabe index (conditional complexity)

    void OnCommand(CONTROL_ID id) {
        LPWSTR defaultDir = nullptr;
        LPWSTR targetDir = nullptr;
        LONGLONG elevated, crtInstalled, installAllUsers;
        BOOL checked, launcherChecked;
        WCHAR wzPath[MAX_PATH] = { };
        BROWSEINFOW browseInfo = { };
        PIDLIST_ABSOLUTE pidl = nullptr;
        DWORD pageId;
        HRESULT hr = S_OK;

        switch(id) {
        case ID_CLOSE_BUTTON:
            OnClickCloseButton();
            break;

        // Install commands
        case ID_INSTALL_SIMPLE_BUTTON: __fallthrough;
        case ID_INSTALL_UPGRADE_BUTTON: __fallthrough;
        case ID_INSTALL_BUTTON:
            SavePageSettings();

            hr = BalGetNumericVariable(L"InstallAllUsers", &installAllUsers);
            ExitOnFailure(hr, L"Failed to get install scope");

            hr = _engine->SetVariableNumeric(L"CompileAll", installAllUsers);
            ExitOnFailure(hr, L"Failed to update CompileAll");

            hr = EnsureTargetDir();
            ExitOnFailure(hr, L"Failed to set TargetDir");

            OnPlan(BOOTSTRAPPER_ACTION_INSTALL);
            break;

        case ID_CUSTOM1_BACK_BUTTON:
            SavePageSettings();
            if (_modifying) {
                GoToPage(PAGE_MODIFY);
            } else if (_upgrading) {
                GoToPage(PAGE_UPGRADE);
            } else {
                GoToPage(PAGE_INSTALL);
            }
            break;

        case ID_INSTALL_CUSTOM_BUTTON: __fallthrough;
        case ID_INSTALL_UPGRADE_CUSTOM_BUTTON: __fallthrough;
        case ID_CUSTOM2_BACK_BUTTON:
            SavePageSettings();
            GoToPage(PAGE_CUSTOM1);
            break;

        case ID_CUSTOM_NEXT_BUTTON:
            SavePageSettings();
            GoToPage(PAGE_CUSTOM2);
            break;

        case ID_CUSTOM_INSTALL_BUTTON:
            SavePageSettings();

            hr = EnsureTargetDir();
            ExitOnFailure(hr, L"Failed to set TargetDir");

            hr = BalGetStringVariable(L"TargetDir", &targetDir);
            if (SUCCEEDED(hr)) {
                // TODO: Check whether directory exists and contains another installation
                ReleaseStr(targetDir);
            }

            OnPlan(_command.action);
            break;

        case ID_INSTALL_LAUNCHER_ALL_USERS_CHECKBOX:
            checked = ThemeIsControlChecked(_theme, ID_INSTALL_LAUNCHER_ALL_USERS_CHECKBOX);
            _engine->SetVariableNumeric(L"InstallLauncherAllUsers", checked);

            ThemeControlElevates(_theme, ID_INSTALL_BUTTON, WillElevate());
            break;

        case ID_CUSTOM_INSTALL_LAUNCHER_ALL_USERS_CHECKBOX:
            checked = ThemeIsControlChecked(_theme, ID_CUSTOM_INSTALL_LAUNCHER_ALL_USERS_CHECKBOX);
            _engine->SetVariableNumeric(L"InstallLauncherAllUsers", checked);

            ThemeControlElevates(_theme, ID_CUSTOM_INSTALL_BUTTON, WillElevate());
            break;

        case ID_CUSTOM_INSTALL_ALL_USERS_CHECKBOX:
            checked = ThemeIsControlChecked(_theme, ID_CUSTOM_INSTALL_ALL_USERS_CHECKBOX);
            _engine->SetVariableNumeric(L"InstallAllUsers", checked);

            ThemeControlElevates(_theme, ID_CUSTOM_INSTALL_BUTTON, WillElevate());
            ThemeControlEnable(_theme, ID_CUSTOM_BROWSE_BUTTON_LABEL, !checked);
            if (checked) {
                _engine->SetVariableNumeric(L"CompileAll", 1);
                ThemeSendControlMessage(_theme, ID_CUSTOM_COMPILE_ALL_CHECKBOX, BM_SETCHECK, BST_CHECKED, 0);
            }
            ThemeGetTextControl(_theme, ID_TARGETDIR_EDITBOX, &targetDir);
            if (targetDir) {
                // Check the current value against the default to see
                // if we should switch it automatically.
                hr = BalGetStringVariable(
                    checked ? L"DefaultJustForMeTargetDir" : L"DefaultAllUsersTargetDir",
                    &defaultDir
                );
                
                if (SUCCEEDED(hr) && defaultDir) {
                    LPWSTR formatted = nullptr;
                    if (defaultDir[0] && SUCCEEDED(BalFormatString(defaultDir, &formatted))) {
                        if (wcscmp(formatted, targetDir) == 0) {
                            ReleaseStr(defaultDir);
                            defaultDir = nullptr;
                            ReleaseStr(formatted);
                            formatted = nullptr;
                            
                            hr = BalGetStringVariable(
                                checked ? L"DefaultAllUsersTargetDir" : L"DefaultJustForMeTargetDir",
                                &defaultDir
                            );
                            if (SUCCEEDED(hr) && defaultDir && defaultDir[0] && SUCCEEDED(BalFormatString(defaultDir, &formatted))) {
                                ThemeSetTextControl(_theme, ID_TARGETDIR_EDITBOX, formatted);
                                ReleaseStr(formatted);
                            }
                        } else {
                            ReleaseStr(formatted);
                        }
                    }
                    
                    ReleaseStr(defaultDir);
                }
            }
            break;

        case ID_CUSTOM_BROWSE_BUTTON:
            browseInfo.hwndOwner = _hWnd;
            browseInfo.pszDisplayName = wzPath;
            browseInfo.lpszTitle = _theme->sczCaption;
            browseInfo.ulFlags = BIF_RETURNONLYFSDIRS | BIF_USENEWUI;
            pidl = ::SHBrowseForFolderW(&browseInfo);
            if (pidl && ::SHGetPathFromIDListW(pidl, wzPath)) {
                ThemeSetTextControl(_theme, ID_TARGETDIR_EDITBOX, wzPath);
            }

            if (pidl) {
                ::CoTaskMemFree(pidl);
            }
            break;

        // Modify commands
        case ID_MODIFY_BUTTON:
            // Some variables cannot be modified
            _engine->SetVariableString(L"InstallAllUsersState", L"disable");
            _engine->SetVariableString(L"InstallLauncherAllUsersState", L"disable");
            _engine->SetVariableString(L"TargetDirState", L"disable");
            _engine->SetVariableString(L"CustomBrowseButtonState", L"disable");
            _modifying = TRUE;
            GoToPage(PAGE_CUSTOM1);
            break;

        case ID_REPAIR_BUTTON:
            OnPlan(BOOTSTRAPPER_ACTION_REPAIR);
            break;

        case ID_UNINSTALL_BUTTON:
            OnPlan(BOOTSTRAPPER_ACTION_UNINSTALL);
            break;

        case ID_SUCCESS_MAX_PATH_BUTTON:
            EnableMaxPathSupport();
            ThemeControlEnable(_theme, ID_SUCCESS_MAX_PATH_BUTTON, FALSE);
            break;
        }

    LExit:
        return;
    }