AppStartPage.cpp

// Copyright (C) Microsoft Corporation. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "stdafx.h"

#include <pathcch.h>
#include <psapi.h>

#include "AppStartPage.h"
#include "AppWindow.h"
#include "CheckFailure.h"

using namespace Microsoft::WRL;

namespace AppStartPage
{

bool AreFileUrisEqual(std::wstring leftUri, std::wstring rightUri)
{
    // Have to to lower due to current bug
    std::transform(leftUri.begin(), leftUri.end(),
            leftUri.begin(), ::tolower);
    std::transform(rightUri.begin(), rightUri.end(),
            rightUri.begin(), ::tolower);

    return leftUri == rightUri;
}

std::wstring ResolvePathAndTrimFile(std::wstring path)
{
    wchar_t resultPath[MAX_PATH];
    PathCchCanonicalize(resultPath, ARRAYSIZE(resultPath), path.c_str());
    PathCchRemoveFileSpec(resultPath, ARRAYSIZE(resultPath));
    return resultPath;
}

std::wstring GetSdkBuild()
{
    auto options = Microsoft::WRL::Make<CoreWebView2EnvironmentOptions>();
    wil::unique_cotaskmem_string targetVersion;
    CHECK_FAILURE(options->get_TargetCompatibleBrowserVersion(&targetVersion));

    // The full version string A.B.C.D
    const wchar_t* targetVersionMajorAndRest = targetVersion.get();
    // Should now be .B.C.D
    const wchar_t* targetVersionMinorAndRest = wcschr(targetVersionMajorAndRest, L'.');
    CHECK_FAILURE((targetVersionMinorAndRest != nullptr && *targetVersionMinorAndRest == L'.') ? S_OK : E_UNEXPECTED);

    // Should now be .C.D
    const wchar_t* targetVersionBuildAndRest = wcschr(targetVersionMinorAndRest + 1, L'.');
    CHECK_FAILURE((targetVersionBuildAndRest != nullptr && *targetVersionBuildAndRest == L'.') ? S_OK : E_UNEXPECTED);

    // Return + 1 to skip the first . so just C.D
    return targetVersionBuildAndRest + 1;
}

std::wstring GetRuntimeVersion(AppWindow* appWindow)
{
    wil::com_ptr<ICoreWebView2Environment> environment = appWindow->GetWebViewEnvironment();
    wil::unique_cotaskmem_string runtimeVersion;
    CHECK_FAILURE(environment->get_BrowserVersionString(&runtimeVersion));

    return runtimeVersion.get();
}

std::wstring GetAppPath()
{
    wchar_t appPath[MAX_PATH];
    GetModuleFileName(nullptr, appPath, ARRAYSIZE(appPath));
    return ResolvePathAndTrimFile(appPath);
}

std::wstring GetRuntimePath(AppWindow* appWindow)
{
    wil::com_ptr<ICoreWebView2> webview = appWindow->GetWebView();
    UINT32 browserProcessId = 0;
    wchar_t runtimePath[MAX_PATH];
    CHECK_FAILURE(webview->get_BrowserProcessId(&browserProcessId));

    HANDLE processHandle = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ, FALSE, browserProcessId);
    CHECK_FAILURE(processHandle == nullptr ? E_FAIL : S_OK);
    GetModuleFileNameEx(processHandle, nullptr, runtimePath, ARRAYSIZE(runtimePath));
    CloseHandle(processHandle);

    return ResolvePathAndTrimFile(runtimePath);
}

// Returns the actual user data folder in use by the current WebView2
// environment. Empty if the environment doesn't support querying it
// (ICoreWebView2Environment7 unavailable).
std::wstring GetUserDataFolder(AppWindow* appWindow)
{
    wil::com_ptr<ICoreWebView2Environment> environment = appWindow->GetWebViewEnvironment();
    auto environment7 = environment.try_query<ICoreWebView2Environment7>();
    if (!environment7)
        return L"";

    wil::unique_cotaskmem_string userDataFolder;
    if (FAILED(environment7->get_UserDataFolder(&userDataFolder)) || !userDataFolder)
        return L"";
    return userDataFolder.get();
}

// Classifies a user data folder as shared when it lives under the shared
// cluster root, mirroring the detection the browser itself uses.
std::wstring GetUserDataFolderKind(const std::wstring& userDataFolder)
{
    if (userDataFolder.empty())
        return L"Unknown";

    std::wstring lowerUserDataFolder = userDataFolder;
    std::transform(
        lowerUserDataFolder.begin(), lowerUserDataFolder.end(), lowerUserDataFolder.begin(),
        ::towlower);
    return lowerUserDataFolder.find(L"\\microsoft\\webview2clusters\\") != std::wstring::npos
               ? L"Shared (cluster)"
               : L"Non-shared";
}

// Percent-encodes the characters that would otherwise be read as query string
// syntax. The folder carries a user-chosen name that may contain '&' or '=',
// either of which would split the value and blank the field.
std::wstring EscapeForQuery(const std::wstring& value)
{
    static constexpr wchar_t kHexDigits[] = L"0123456789ABCDEF";
    std::wstring escaped;
    escaped.reserve(value.size());
    for (const wchar_t c : value)
    {
        if (c == L'&' || c == L'=' || c == L'%' || c == L'#' || c == L'?' || c == L'+')
        {
            escaped.push_back(L'%');
            escaped.push_back(kHexDigits[(c >> 4) & 0xF]);
            escaped.push_back(kHexDigits[c & 0xF]);
        }
        else
        {
            escaped.push_back(c);
        }
    }
    return escaped;
}

std::wstring GetUri(AppWindow* appWindow)
{
    std::wstring uri = appWindow->GetLocalUri(L"AppStartPage.html", true);

    uri += L"?sdkBuild=";
    uri += GetSdkBuild();

    uri += L"&runtimeVersion=";
    uri += GetRuntimeVersion(appWindow);

    uri += L"&appPath=";
    uri += GetAppPath();

    uri += L"&runtimePath=";
    uri += GetRuntimePath(appWindow);

    std::wstring userDataFolder = GetUserDataFolder(appWindow);
    uri += L"&userDataFolder=";
    uri += EscapeForQuery(userDataFolder);

    uri += L"&userDataFolderKind=";
    uri += GetUserDataFolderKind(userDataFolder);

    return uri;
}

}; // namespace AppStartPage