/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/**
 * This file exists so that LaunchModernSettingsDialogDefaultApps can be called
 * without linking to libxul.
 */
#include "WindowsDefaultBrowser.h"

#include "city.h"
#include "mozilla/RefPtr.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/WindowsVersion.h"
#include "mozilla/WinHeaderOnlyUtils.h"

// This must be before any other includes that might include shlobj.h
#define INITGUID
#include <shlobj.h>

#include <lm.h>
#include <shellapi.h>
#include <shlwapi.h>
#include <uiautomation.h>
#include <wchar.h>
#include <windows.h>

#define APP_REG_NAME_BASE L"Firefox-"

static bool IsWindowsLogonConnected() {
  WCHAR userName[UNLEN + 1];
  DWORD size = std::size(userName);
  if (!GetUserNameW(userName, &size)) {
    return false;
  }

  LPUSER_INFO_24 info;
  if (NetUserGetInfo(nullptr, userName, 24, (LPBYTE*)&info) != NERR_Success) {
    return false;
  }
  bool connected = info->usri24_internet_identity;
  NetApiBufferFree(info);

  return connected;
}

static bool SettingsAppBelievesConnected() {
  const wchar_t* keyPath = L"SOFTWARE\\Microsoft\\Windows\\Shell\\Associations";
  const wchar_t* valueName = L"IsConnectedAtLogon";

  uint32_t value = 0;
  DWORD size = sizeof(uint32_t);
  LSTATUS ls = RegGetValueW(HKEY_CURRENT_USER, keyPath, valueName, RRF_RT_ANY,
                            nullptr, &value, &size);
  if (ls != ERROR_SUCCESS) {
    return false;
  }

  return !!value;
}

bool GetAppRegName(mozilla::UniquePtr<wchar_t[]>& aAppRegName) {
  mozilla::UniquePtr<wchar_t[]> appDirStr;
  bool success = mozilla::GetInstallDirectory(appDirStr);
  if (!success) {
    return success;
  }

  uint64_t hash = CityHash64(reinterpret_cast<char*>(appDirStr.get()),
                             wcslen(appDirStr.get()) * sizeof(wchar_t));

  const wchar_t* format = L"%s%I64X";
  int bufferSize = _scwprintf(format, APP_REG_NAME_BASE, hash);
  ++bufferSize;  // Extra byte for terminating null
  aAppRegName = mozilla::MakeUnique<wchar_t[]>(bufferSize);

  _snwprintf_s(aAppRegName.get(), bufferSize, _TRUNCATE, format,
               APP_REG_NAME_BASE, hash);

  return success;
}

bool LaunchControlPanelDefaultPrograms() {
  // Build the path control.exe path safely
  WCHAR controlEXEPath[MAX_PATH + 1] = {'\0'};
  if (!GetSystemDirectoryW(controlEXEPath, MAX_PATH)) {
    return false;
  }
  LPCWSTR controlEXE = L"control.exe";
  if (wcslen(controlEXEPath) + wcslen(controlEXE) >= MAX_PATH) {
    return false;
  }
  if (!PathAppendW(controlEXEPath, controlEXE)) {
    return false;
  }

  const wchar_t* paramFormat =
      L"control.exe /name Microsoft.DefaultPrograms "
      L"/page pageDefaultProgram\\pageAdvancedSettings?pszAppName=%s";
  mozilla::UniquePtr<wchar_t[]> appRegName;
  GetAppRegName(appRegName);
  int bufferSize = _scwprintf(paramFormat, appRegName.get());
  ++bufferSize;  // Extra byte for terminating null
  mozilla::UniquePtr<wchar_t[]> params =
      mozilla::MakeUnique<wchar_t[]>(bufferSize);
  _snwprintf_s(params.get(), bufferSize, _TRUNCATE, paramFormat,
               appRegName.get());

  STARTUPINFOW si = {sizeof(si), 0};
  si.dwFlags = STARTF_USESHOWWINDOW;
  si.wShowWindow = SW_SHOWDEFAULT;
  PROCESS_INFORMATION pi = {0};
  if (!CreateProcessW(controlEXEPath, params.get(), nullptr, nullptr, FALSE, 0,
                      nullptr, nullptr, &si, &pi)) {
    return false;
  }
  CloseHandle(pi.hProcess);
  CloseHandle(pi.hThread);

  return true;
}

static bool IsAppRegistered(HKEY rootKey, const wchar_t* appRegName) {
  const wchar_t* keyPath = L"Software\\RegisteredApplications";

  DWORD size = sizeof(uint32_t);
  LSTATUS ls = RegGetValueW(rootKey, keyPath, appRegName, RRF_RT_ANY, nullptr,
                            nullptr, &size);
  return ls == ERROR_SUCCESS;
}

static bool LaunchMsSettingsProtocol() {
  mozilla::UniquePtr<wchar_t[]> params = nullptr;
  if (mozilla::HasPackageIdentity()) {
    mozilla::UniquePtr<wchar_t[]> packageFamilyName =
        mozilla::GetPackageFamilyName();
    if (packageFamilyName) {
      const wchar_t* paramFormat =
          L"ms-settings:defaultapps?registeredAUMID=%s!App";
      int bufferSize = _scwprintf(paramFormat, packageFamilyName.get());
      ++bufferSize;  // Extra byte for terminating null
      params = mozilla::MakeUnique<wchar_t[]>(bufferSize);
      _snwprintf_s(params.get(), bufferSize, _TRUNCATE, paramFormat,
                   packageFamilyName.get());
    }
  }
  if (!params) {
    mozilla::UniquePtr<wchar_t[]> appRegName;
    GetAppRegName(appRegName);
    const wchar_t* paramFormat =
        IsAppRegistered(HKEY_CURRENT_USER, appRegName.get()) ||
                !IsAppRegistered(HKEY_LOCAL_MACHINE, appRegName.get())
            ? L"ms-settings:defaultapps?registeredAppUser=%s"
            : L"ms-settings:defaultapps?registeredAppMachine=%s";
    int bufferSize = _scwprintf(paramFormat, appRegName.get());
    ++bufferSize;  // Extra byte for terminating null
    params = mozilla::MakeUnique<wchar_t[]>(bufferSize);
    _snwprintf_s(params.get(), bufferSize, _TRUNCATE, paramFormat,
                 appRegName.get());
  }

  SHELLEXECUTEINFOW seinfo = {sizeof(seinfo)};
  seinfo.lpFile = params.get();
  seinfo.nShow = SW_SHOWNORMAL;
  return ShellExecuteExW(&seinfo);
}

bool LaunchModernSettingsDialogDefaultApps() {
  if (mozilla::IsWin11OrLater()) {
    return LaunchMsSettingsProtocol();
  }

  if (!mozilla::IsWindows10BuildOrLater(14965) && !IsWindowsLogonConnected() &&
      SettingsAppBelievesConnected()) {
    // Use the classic Control Panel to work around a bug of older
    // builds of Windows 10.
    return LaunchControlPanelDefaultPrograms();
  }

  IApplicationActivationManager* pActivator;
  HRESULT hr = CoCreateInstance(
      CLSID_ApplicationActivationManager, nullptr, CLSCTX_INPROC,
      IID_IApplicationActivationManager, (void**)&pActivator);

  if (SUCCEEDED(hr)) {
    DWORD pid;
    hr = pActivator->ActivateApplication(
        L"windows.immersivecontrolpanel_cw5n1h2txyewy"
        L"!microsoft.windows.immersivecontrolpanel",
        L"page=SettingsPageAppsDefaults", AO_NONE, &pid);
    if (SUCCEEDED(hr)) {
      // Do not check error because we could at least open
      // the "Default apps" setting.
      pActivator->ActivateApplication(
          L"windows.immersivecontrolpanel_cw5n1h2txyewy"
          L"!microsoft.windows.immersivecontrolpanel",
          L"page=SettingsPageAppsDefaults"
          L"&target=SystemSettings_DefaultApps_Browser",
          AO_NONE, &pid);
    }
    pActivator->Release();
    return SUCCEEDED(hr);
  }
  return true;
}

static already_AddRefed<IUIAutomationElement> TryFindElementByAutomationId(
    HWND aWindow, LPCWSTR aId) {
  RefPtr<IUIAutomation> automation;
  HRESULT hr{CoCreateInstance(CLSID_CUIAutomation, nullptr,
                              CLSCTX_INPROC_SERVER, IID_IUIAutomation,
                              getter_AddRefs(automation))};
  if (FAILED(hr)) {
    return nullptr;
  }

  RefPtr<IUIAutomationElement> window;
  hr = automation->ElementFromHandle(aWindow, getter_AddRefs(window));
  if (FAILED(hr)) {
    return nullptr;
  }

  VARIANT value{};
  value.vt = VT_BSTR;
  value.bstrVal = SysAllocString(aId);
  RefPtr<IUIAutomationCondition> propertyCondition;
  hr = automation->CreatePropertyCondition(UIA_AutomationIdPropertyId, value,
                                           getter_AddRefs(propertyCondition));
  SysFreeString(value.bstrVal);
  if (FAILED(hr)) {
    return nullptr;
  }

  RefPtr<IUIAutomationElement> element;
  hr = window->FindFirst(TreeScope_Descendants, propertyCondition,
                         getter_AddRefs(element));
  if (SUCCEEDED(hr) && element) {
    return element.forget();
  }

  return nullptr;
}

static bool PathHasFilename(LPCWSTR aPath, LPCWSTR aFilename) {
  LPCWSTR fileName{::wcsrchr(aPath, L'\\')};
  fileName = fileName ? fileName + 1 : aPath;
  return ::_wcsicmp(fileName, aFilename) == 0;
}

static bool IsSystemSettingsProcessByPid(DWORD aPid) {
  nsAutoHandle process{
      ::OpenProcess(PROCESS_QUERY_LIMITED_INFORMATION, FALSE, aPid)};
  if (!process) {
    return false;
  }

  DWORD bufferLength{MAX_PATH};
  auto buffer{mozilla::MakeUnique<wchar_t[]>(bufferLength)};
  if (::QueryFullProcessImageNameW(process, 0, buffer.get(), &bufferLength)) {
    LPCWSTR kProcessName{L"SystemSettings.exe"};
    return PathHasFilename(buffer.get(), kProcessName);
  }
  return false;
}

static bool IsSystemSettingsProcessByHandle(HWND aHwnd) {
  DWORD pid{0};
  ::GetWindowThreadProcessId(aHwnd, &pid);
  return IsSystemSettingsProcessByPid(pid);
}

static BOOL CALLBACK FindSystemSettingsChildProc(HWND aHwnd, LPARAM aLParam) {
  if (IsSystemSettingsProcessByHandle(aHwnd)) {
    *reinterpret_cast<bool*>(aLParam) = true;
    return FALSE;
  }
  return TRUE;
}

static bool IsApplicationFrameWindow(HWND aHwnd) {
  WCHAR className[MAX_PATH]{};
  ::GetClassNameW(aHwnd, className, std::size(className));
  LPCWSTR kClassName{L"ApplicationFrameWindow"};
  return (wcscmp(className, kClassName) == 0);
}

static BOOL CALLBACK FindSystemSettingsProc(HWND aHwnd, LPARAM aLParam) {
  // SystemSettings is hosted inside ApplicationFrameHost, so we first find
  // the ApplicationFrameWindow and then check if SystemSettings is direct child
  if (IsApplicationFrameWindow(aHwnd)) {
    bool hasChild{false};
    ::EnumChildWindows(aHwnd, FindSystemSettingsChildProc,
                       reinterpret_cast<LPARAM>(&hasChild));
    if (hasChild) {
      *reinterpret_cast<HWND*>(aLParam) = aHwnd;
      return FALSE;
    }
  }
  return TRUE;
}

static HWND FindSystemSettingsWindow() {
  HWND hwnd{nullptr};
  ::EnumWindows(FindSystemSettingsProc, reinterpret_cast<LPARAM>(&hwnd));
  return hwnd;
}

static UIWindowElement FindSetDefaultBrowserButtonByAutomationId(LPCWSTR aId) {
  if (HWND window{FindSystemSettingsWindow()}) {
    if (UIElement element{TryFindElementByAutomationId(window, aId)}) {
      return {window, element};
    }
  }
  return {};
}

static LPCWSTR GetSetDefaultBrowserButtonAutomationId() {
  // clang-format off
  LPCWSTR kWin11AutomationId{L"SystemSettings_DefaultApps_DefaultBrowserWithPinToStartAndTaskbarAction_Button"};
  LPCWSTR kWin10AutomationId{L"SystemSettings_DefaultApps_Browser_Button"};
  // clang-format on
  return mozilla::IsWin11OrLater() ? kWin11AutomationId : kWin10AutomationId;
}

[[nodiscard]] UIWindowElement FindSetDefaultBrowserButton() {
  LPCWSTR id{GetSetDefaultBrowserButtonAutomationId()};
  return FindSetDefaultBrowserButtonByAutomationId(id);
}