calculator/src/CalcViewModel/HistoryViewModel.cpp

380 lines
13 KiB
C++

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.
#include "pch.h"
#include "HistoryViewModel.h"
#include "Common/TraceLogger.h"
#include "Common/LocalizationStringUtil.h"
#include "Common/LocalizationSettings.h"
using namespace CalculatorApp;
using namespace CalculatorApp::Common;
using namespace CalculatorApp::Common::Automation;
using namespace CalculatorApp::ViewModel;
using namespace Platform;
using namespace std;
using namespace Windows::Foundation;
using namespace Windows::Storage;
using namespace Windows::Storage::Streams;
using namespace Windows::Security::Cryptography;
using namespace Windows::Foundation::Collections;
static StringReference HistoryVectorLengthKey{ L"HistoryVectorLength" };
namespace CalculatorApp::ViewModel::HistoryResourceKeys
{
StringReference HistoryCleared(L"HistoryList_Cleared");
}
HistoryViewModel::HistoryViewModel(_In_ CalculationManager::CalculatorManager* calculatorManager)
: m_calculatorManager(calculatorManager)
, m_localizedHistoryCleared(nullptr)
{
AreHistoryShortcutsEnabled = true;
Items = ref new Platform::Collections::Vector<HistoryItemViewModel ^>();
ItemSize = 0;
}
void HistoryViewModel::RestoreCompleteHistory()
{
RestoreHistory(CalculationManager::CALCULATOR_MODE::CM_STD);
RestoreHistory(CalculationManager::CALCULATOR_MODE::CM_SCI);
}
// this will reload Items with the history list based on current mode
void HistoryViewModel::ReloadHistory(_In_ ViewMode currentMode)
{
if (currentMode == ViewMode::Standard)
{
m_currentMode = CalculationManager::CALCULATOR_MODE::CM_STD;
}
else if (currentMode == ViewMode::Scientific)
{
m_currentMode = CalculationManager::CALCULATOR_MODE::CM_SCI;
}
else
{
return;
}
auto historyListModel = m_calculatorManager->GetHistoryItems(m_currentMode);
auto historyListVM = ref new Platform::Collections::Vector<HistoryItemViewModel ^>();
const auto& localizer = LocalizationSettings::GetInstance();
if (historyListModel.size() > 0)
{
for (auto ritr = historyListModel.rbegin(); ritr != historyListModel.rend(); ++ritr)
{
wstring expression = (*ritr)->historyItemVector.expression;
wstring result = (*ritr)->historyItemVector.result;
localizer.LocalizeDisplayValue(&expression);
localizer.LocalizeDisplayValue(&result);
auto item = ref new HistoryItemViewModel(
ref new Platform::String(expression.c_str()),
ref new Platform::String(result.c_str()),
(*ritr)->historyItemVector.spTokens,
(*ritr)->historyItemVector.spCommands);
historyListVM->Append(item);
}
}
Items = historyListVM;
UpdateItemSize();
}
void HistoryViewModel::OnHistoryItemAdded(_In_ unsigned int addedItemIndex)
{
auto newItem = m_calculatorManager->GetHistoryItem(addedItemIndex);
const auto& localizer = LocalizationSettings::GetInstance();
wstring expression = newItem->historyItemVector.expression;
wstring result = newItem->historyItemVector.result;
localizer.LocalizeDisplayValue(&expression);
localizer.LocalizeDisplayValue(&result);
auto item = ref new HistoryItemViewModel(
ref new Platform::String(expression.c_str()),
ref new Platform::String(result.c_str()),
newItem->historyItemVector.spTokens,
newItem->historyItemVector.spCommands);
// check if we have not hit the max items
if (Items->Size >= m_calculatorManager->MaxHistorySize())
{
// this means the item already exists
Items->RemoveAt(Items->Size - 1);
}
assert(addedItemIndex <= m_calculatorManager->MaxHistorySize() && addedItemIndex >= 0);
Items->InsertAt(0, item);
UpdateItemSize();
SaveHistory();
}
void HistoryViewModel::SetCalculatorDisplay(CalculatorDisplay& calculatorDisplay)
{
WeakReference historyViewModel(this);
calculatorDisplay.SetHistoryCallback(historyViewModel);
}
void HistoryViewModel::ShowItem(_In_ HistoryItemViewModel ^ e)
{
unsigned int index;
Items->IndexOf(e, &index);
TraceLogger::GetInstance().LogHistoryItemLoad((ViewMode)m_currentMode, ItemSize, (int)(index));
HistoryItemClicked(e);
}
void HistoryViewModel::DeleteItem(_In_ HistoryItemViewModel ^ e)
{
uint32_t itemIndex;
if (Items->IndexOf(e, &itemIndex))
{
if (m_calculatorManager->RemoveHistoryItem(itemIndex))
{
// Keys for the history container are index based.
// SaveHistory() re-inserts the items anyway, so it's faster to just clear out the container.
CalculationManager::CALCULATOR_MODE currentMode = m_currentMode;
ApplicationDataContainer ^ historyContainer = GetHistoryContainer(currentMode);
historyContainer->Values->Clear();
Items->RemoveAt(itemIndex);
UpdateItemSize();
SaveHistory();
}
}
}
void HistoryViewModel::OnHideCommand(_In_ Platform::Object ^ e)
{
// added at VM layer so that the views do not have to individually raise events
HideHistoryClicked();
}
void HistoryViewModel::OnClearCommand(_In_ Platform::Object ^ e)
{
if (AreHistoryShortcutsEnabled == true)
{
m_calculatorManager->ClearHistory();
if (Items->Size > 0)
{
CalculationManager::CALCULATOR_MODE currentMode = m_currentMode;
ClearHistoryContainer(currentMode);
Items->Clear();
UpdateItemSize();
}
MakeHistoryClearedNarratorAnnouncement(HistoryResourceKeys::HistoryCleared, m_localizedHistoryCleared);
}
}
// this method restores history vector per mode
void HistoryViewModel::RestoreHistory(_In_ CalculationManager::CALCULATOR_MODE cMode)
{
ApplicationDataContainer ^ historyContainer = GetHistoryContainer(cMode);
std::shared_ptr<std::vector<std::shared_ptr<CalculationManager::HISTORYITEM>>> historyVector =
std::make_shared<std::vector<std::shared_ptr<CalculationManager::HISTORYITEM>>>();
auto historyVectorLength = static_cast<int>(historyContainer->Values->Lookup(HistoryVectorLengthKey));
bool failure = false;
if (historyVectorLength > 0)
{
for (int i = 0; i < historyVectorLength; ++i)
{
try
{
// deserialize each item
auto item = DeserializeHistoryItem(i.ToString(), historyContainer);
std::shared_ptr<CalculationManager::HISTORYITEM> Item = std::make_shared<CalculationManager::HISTORYITEM>(item);
historyVector->push_back(Item);
}
catch (Platform::Exception ^ e)
{
failure = true;
break;
}
}
if (!failure)
{
// if task has been cancelled set history to 0
m_calculatorManager->SetHistory(cMode, *historyVector);
// update length once again for consistency between stored number of items and length
UpdateHistoryVectorLength(static_cast<int>(historyVector->size()), cMode);
}
else
{
// in case of failure do not show any item
UpdateHistoryVectorLength(0, cMode);
}
}
}
Platform::String ^ HistoryViewModel::GetHistoryContainerKey(_In_ CalculationManager::CALCULATOR_MODE cMode)
{
Platform::ValueType ^ modeValue = static_cast<int>(cMode);
return Platform::String::Concat(modeValue->ToString(), L"_History");
}
ApplicationDataContainer ^ HistoryViewModel::GetHistoryContainer(_In_ CalculationManager::CALCULATOR_MODE cMode)
{
ApplicationDataContainer ^ localSettings = ApplicationData::Current->LocalSettings;
ApplicationDataContainer ^ historyContainer;
// naming container based on mode
Platform::String ^ historyContainerKey = GetHistoryContainerKey(cMode);
if (localSettings->Containers->HasKey(historyContainerKey))
{
historyContainer = localSettings->Containers->Lookup(historyContainerKey);
}
else
{
// create container for adding data
historyContainer = localSettings->CreateContainer(historyContainerKey, ApplicationDataCreateDisposition::Always);
int initialHistoryVectorLength = 0;
historyContainer->Values->Insert(HistoryVectorLengthKey, initialHistoryVectorLength);
}
return historyContainer;
}
void HistoryViewModel::ClearHistoryContainer(_In_ CalculationManager::CALCULATOR_MODE cMode)
{
ApplicationDataContainer ^ localSettings = ApplicationData::Current->LocalSettings;
localSettings->DeleteContainer(GetHistoryContainerKey(cMode));
}
// this method will be used to update the history item length
void HistoryViewModel::UpdateHistoryVectorLength(_In_ int newValue, _In_ CalculationManager::CALCULATOR_MODE cMode)
{
ApplicationDataContainer ^ historyContainer = GetHistoryContainer(cMode);
historyContainer->Values->Remove(HistoryVectorLengthKey);
historyContainer->Values->Insert(HistoryVectorLengthKey, newValue);
}
void HistoryViewModel::ClearHistory()
{
ClearHistoryContainer(CalculationManager::CALCULATOR_MODE::CM_STD);
ClearHistoryContainer(CalculationManager::CALCULATOR_MODE::CM_SCI);
}
void HistoryViewModel::SaveHistory()
{
ApplicationDataContainer ^ historyContainer = GetHistoryContainer(m_currentMode);
auto currentHistoryVector = m_calculatorManager->GetHistoryItems(m_currentMode);
bool failure = false;
int index = 0;
Platform::String ^ serializedHistoryItem;
for (auto iter = currentHistoryVector.begin(); iter != currentHistoryVector.end(); ++iter)
{
try
{
serializedHistoryItem = SerializeHistoryItem(*iter);
historyContainer->Values->Insert(index.ToString(), serializedHistoryItem);
}
catch (Platform::Exception ^)
{
failure = true;
break;
}
++index;
}
if (!failure)
{
// insertion is successful
UpdateHistoryVectorLength(static_cast<int>(currentHistoryVector.size()), m_currentMode);
}
else
{
UpdateHistoryVectorLength(0, m_currentMode);
}
}
// this serializes a history item into a base64 encoded string
Platform::String ^ HistoryViewModel::SerializeHistoryItem(_In_ std::shared_ptr<CalculationManager::HISTORYITEM> const& item)
{
DataWriter ^ writer = ref new DataWriter();
auto expr = item->historyItemVector.expression;
auto result = item->historyItemVector.result;
auto platformExpr = ref new Platform::String(expr.c_str());
writer->WriteUInt32(writer->MeasureString(platformExpr));
writer->WriteString(platformExpr);
auto platformResult = ref new Platform::String(result.c_str());
writer->WriteUInt32(writer->MeasureString(platformResult));
writer->WriteString(platformResult);
Utils::SerializeCommandsAndTokens(item->historyItemVector.spTokens, item->historyItemVector.spCommands, writer);
IBuffer ^ buffer = writer->DetachBuffer();
if (buffer == nullptr)
{
throw ref new Platform::Exception(E_POINTER, ref new Platform::String(L"History Item is NULL"));
}
return CryptographicBuffer::EncodeToBase64String(buffer);
}
CalculationManager::HISTORYITEM
HistoryViewModel::DeserializeHistoryItem(_In_ Platform::String ^ historyItemKey, _In_ ApplicationDataContainer ^ historyContainer)
{
CalculationManager::HISTORYITEM historyItem;
if (historyContainer->Values->HasKey(historyItemKey))
{
Object ^ historyItemValues = historyContainer->Values->Lookup(historyItemKey);
if (historyItemValues == nullptr)
{
throw ref new Platform::Exception(E_POINTER, ref new Platform::String(L"History Item is NULL"));
}
String ^ historyData = safe_cast<Platform::String ^>(historyItemValues);
IBuffer ^ buffer = CryptographicBuffer::DecodeFromBase64String(historyData);
if (buffer == nullptr)
{
throw ref new Platform::Exception(E_POINTER, ref new Platform::String(L"History Item is NULL"));
}
DataReader ^ reader = DataReader::FromBuffer(buffer);
auto exprLen = reader->ReadUInt32();
auto expression = reader->ReadString(exprLen);
historyItem.historyItemVector.expression = expression->Data();
auto resultLen = reader->ReadUInt32();
auto result = reader->ReadString(resultLen);
historyItem.historyItemVector.result = result->Data();
historyItem.historyItemVector.spCommands = Utils::DeserializeCommands(reader);
historyItem.historyItemVector.spTokens = Utils::DeserializeTokens(reader);
}
else
{
throw ref new Platform::Exception(E_ACCESSDENIED, ref new Platform::String(L"History Item not found"));
}
return historyItem;
}
bool HistoryViewModel::IsValid(_In_ CalculationManager::HISTORYITEM item)
{
return (
!item.historyItemVector.expression.empty() && !item.historyItemVector.result.empty() && (bool)item.historyItemVector.spCommands
&& (bool)item.historyItemVector.spTokens);
}
void HistoryViewModel::UpdateItemSize()
{
ItemSize = Items->Size;
}
void HistoryViewModel::MakeHistoryClearedNarratorAnnouncement(String ^ resourceKey, String ^ &formatVariable)
{
String ^ announcement = LocalizationStringUtil::GetLocalizedNarratorAnnouncement(resourceKey, formatVariable);
HistoryAnnouncement = CalculatorAnnouncement::GetHistoryClearedAnnouncement(announcement);
}