Transfer: implement 'Grab QR code from screen' functionality

pages/Transfer.qml

@@ -93,12 +93,16 @@ Rectangle {
       oaPopup.open()
     }
 
-    function updateFromQrCode(address, payment_id, amount, tx_description, recipient_name) {
-        console.log("updateFromQrCode")
+    function fillPaymentDetails(address, payment_id, amount, tx_description, recipient_name) {
         addressLine.text = address
         setPaymentId(payment_id);
         amountLine.text = amount
         setDescription((recipient_name ? recipient_name + " " : "") + tx_description);
+    }
+
+    function updateFromQrCode(address, payment_id, amount, tx_description, recipient_name) {
+        console.log("updateFromQrCode")
+        fillPaymentDetails(address, payment_id, amount, tx_description, recipient_name);
         cameraUi.qrcode_decoded.disconnect(updateFromQrCode)
     }
 
@@ -196,6 +200,23 @@ Rectangle {
                   }
               }
 
+                MoneroComponents.InlineButton {
+                    fontFamily: FontAwesome.fontFamily
+                    fontPixelSize: 18
+                    text: FontAwesome.desktop
+                    onClicked: {
+                        clearFields();
+                        const codes = oshelper.grabQrCodesFromScreen();
+                        for (var index = 0; index < codes.length; ++index) {
+                            const parsed = walletManager.parse_uri_to_object(codes[index]);
+                            if (!parsed.error) {
+                                fillPaymentDetails(parsed.address, parsed.payment_id, parsed.amount, parsed.tx_description, parsed.recipient_name);
+                                break;
+                            }
+                        }
+                    }
+                }
+
                 MoneroComponents.InlineButton {
                     fontFamily: FontAwesome.fontFamily
                     text: FontAwesome.addressBook

src/QR-Code-scanner/Decoder.cpp

@@ -1,3 +1,31 @@
+// Copyright (c) 2020, The Monero Project
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
 #include "Decoder.h"
 
 #include <limits>

src/QR-Code-scanner/Decoder.h

@@ -1,3 +1,31 @@
+// Copyright (c) 2020, The Monero Project
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
 #include <QImage>
 
 struct quirc;

src/main/oshelper.cpp

@@ -27,10 +27,16 @@
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include "oshelper.h"
+
+#include <unordered_set>
+
 #include <QCoreApplication>
+#include <QGuiApplication>
 #include <QFileDialog>
+#include <QScreen>
 #include <QStandardPaths>
 #include <QTemporaryFile>
+#include <QWindow>
 #include <QDir>
 #include <QDebug>
 #include <QDesktopServices>
@@ -55,6 +61,40 @@
 #include "qt/utils.h"
 #endif
 
+#include "QR-Code-scanner/Decoder.h"
+#include "qt/ScopeGuard.h"
+
+namespace
+{
+
+QPixmap screenshot()
+{
+#ifdef Q_OS_MAC
+    return MacOSHelper::screenshot();
+#else
+    std::unordered_set<QWindow *> hidden;
+    const QWindowList windows = QGuiApplication::allWindows();
+    for (QWindow *window : windows)
+    {
+        if (window->isVisible())
+        {
+            hidden.emplace(window);
+            window->hide();
+        }
+    }
+    const auto unhide = sg::make_scope_guard([&hidden]() {
+        for (QWindow *window : hidden)
+        {
+            window->show();
+        }
+    });
+
+    return QGuiApplication::primaryScreen()->grabWindow(0);
+#endif
+}
+
+} // namespace
+
 #if defined(Q_OS_WIN)
 bool openFolderAndSelectItem(const QString &filePath)
 {
@@ -99,6 +139,26 @@ QString OSHelper::downloadLocation() const
     return QStandardPaths::writableLocation(QStandardPaths::DownloadLocation);
 }
 
+QList<QString> OSHelper::grabQrCodesFromScreen() const
+{
+    QList<QString> codes;
+
+    try
+    {
+        const QImage image = screenshot().toImage();
+        const std::vector<std::string> decoded = QrDecoder().decode(image);
+        std::for_each(decoded.begin(), decoded.end(), [&codes](const std::string &code) {
+            codes.push_back(QString::fromStdString(code));
+        });
+    }
+    catch (const std::exception &e)
+    {
+        qWarning() << e.what();
+    }
+
+    return codes;
+}
+
 bool OSHelper::openContainingFolder(const QString &filePath) const
 {
     QString canonicalFilePath = QFileInfo(filePath).canonicalFilePath();

src/main/oshelper.h

@@ -29,7 +29,9 @@
 #ifndef OSHELPER_H
 #define OSHELPER_H
 
+#include <QList>
 #include <QObject>
+#include <QString>
 /**
  * @brief The OSHelper class - exports to QML some OS-related functions
  */
@@ -43,6 +45,7 @@ public:
 
     Q_INVOKABLE void createDesktopEntry() const;
     Q_INVOKABLE QString downloadLocation() const;
+    Q_INVOKABLE QList<QString> grabQrCodesFromScreen() const;
     Q_INVOKABLE bool openContainingFolder(const QString &filePath) const;
     Q_INVOKABLE QString openSaveFileDialog(const QString &title, const QString &folder, const QString &filename) const;
     Q_INVOKABLE QString temporaryFilename() const;

src/qt/macoshelper.h

@@ -29,6 +29,8 @@
 #ifndef MACOSHELPER_H
 #define MACOSHELPER_H
 
+#include <QPixmap>
+
 class MacOSHelper
 {
     MacOSHelper() {}
@@ -36,6 +38,7 @@ class MacOSHelper
 public:
     static bool isCapsLock();
     static bool openFolderAndSelectItem(const QUrl &path);
+    static QPixmap screenshot();
     static QString bundlePath();
 };
 

src/qt/macoshelper.mm

@@ -26,6 +26,8 @@
 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+#include <unordered_set>
+
 #include <QtCore>
 #include <QtGui>
 #include <QtMac>
@@ -37,6 +39,8 @@
 #include <ApplicationServices/ApplicationServices.h>
 #include <Availability.h>
 
+#include "ScopeGuard.h"
+
 bool MacOSHelper::isCapsLock()
 {
 #ifdef __MAC_10_12
@@ -56,6 +60,41 @@ bool MacOSHelper::openFolderAndSelectItem(const QUrl &path)
     return true;
 }
 
+QPixmap MacOSHelper::screenshot()
+{
+    std::unordered_set<uintptr_t> appWindowIds;
+    for (NSWindow *window in [NSApp windows])
+    {
+        appWindowIds.insert((uintptr_t)[window windowNumber]);
+    }
+
+    CFArrayRef onScreenWindows = CGWindowListCreate(kCGWindowListOptionOnScreenOnly, kCGNullWindowID);
+    const auto onScreenWindowsClenaup = sg::make_scope_guard([&onScreenWindows]() {
+        CFRelease(onScreenWindows);
+    });
+
+    CFMutableArrayRef foreignWindows = CFArrayCreateMutable(NULL, CFArrayGetCount(onScreenWindows), NULL);
+    const auto foreignWindowsClenaup = sg::make_scope_guard([&foreignWindows]() {
+        CFRelease(foreignWindows);
+    });
+
+    for (CFIndex index = 0, count = CFArrayGetCount(onScreenWindows); index < count; ++index)
+    {
+        const uintptr_t windowId = reinterpret_cast<const uintptr_t>(CFArrayGetValueAtIndex(onScreenWindows, index));
+        if (appWindowIds.find(windowId) == appWindowIds.end())
+        {
+            CFArrayAppendValue(foreignWindows, reinterpret_cast<const void *>(windowId));
+        }
+    }
+
+    CGImageRef image = CGWindowListCreateImageFromArray(CGRectInfinite, foreignWindows, kCGWindowListOptionAll);
+    const auto imageClenaup = sg::make_scope_guard([&image]() {
+        CFRelease(image);
+    });
+
+    return QtMac::fromCGImageRef(image);
+}
+
 QString MacOSHelper::bundlePath()
 {
     NSBundle *main = [NSBundle mainBundle];