#include "s60devices.h"

#include <QtCore/QSettings>
#include <QtCore/QXmlStreamReader>
#include <QtCore/QFile>
#include <QtCore/QDir>

namespace {
    const char * const SYMBIAN_SDKS_KEY = "HKEY_LOCAL_MACHINE\\Software\\Symbian\\EPOC SDKs";
    const char * const SYMBIAN_PATH_KEY = "CommonPath";
    const char * const SYMBIAN_DEVICES_FILE = "devices.xml";
    const char * const DEVICES_LIST = "devices";
    const char * const DEVICE = "device";
    const char * const DEVICE_ID = "id";
    const char * const DEVICE_NAME = "name";
    const char * const DEVICE_DEFAULT = "default";
    const char * const DEVICE_EPOCROOT = "epocroot";
    const char * const DEVICE_TOOLSROOT = "toolsroot";
}

using namespace Qt4ProjectManager::Internal;

S60Devices::S60Devices(QObject *parent)
        : QObject(parent)
{
}

bool S60Devices::read()
{
    m_devices.clear();
    m_errorString = QString();
    // Check the windows registry via QSettings for devices.xml path
    QSettings settings(SYMBIAN_SDKS_KEY, QSettings::NativeFormat);
    QString devicesXmlPath = settings.value(SYMBIAN_PATH_KEY).toString();
    if (devicesXmlPath.isEmpty()) {
        m_errorString = "Could not find installed SDKs in registry.";
        return false;
    }

    devicesXmlPath += QLatin1String("/") + QLatin1String(SYMBIAN_DEVICES_FILE);
    QFile devicesFile(devicesXmlPath);
    if (!devicesFile.open(QIODevice::ReadOnly)) {
        m_errorString = QString("Could not read devices file at %1.").arg(devicesXmlPath);
        return false;
    }
    QXmlStreamReader xml(&devicesFile);
    while (!xml.atEnd()) {
        xml.readNext();
        if (xml.isStartElement() && xml.name() == DEVICES_LIST) {
            if (xml.attributes().value("version") == "1.0") {
                // Look for correct device
                while (!(xml.isEndElement() && xml.name() == DEVICES_LIST) && !xml.atEnd()) {
                    xml.readNext();
                    if (xml.isStartElement() && xml.name() == DEVICE) {
                        Device device;
                        device.id = xml.attributes().value(DEVICE_ID).toString();
                        device.name = xml.attributes().value(DEVICE_NAME).toString();
                        if (xml.attributes().value(DEVICE_DEFAULT).toString() == "yes")
                            device.isDefault = true;
                        else
                            device.isDefault = false;
                        while (!(xml.isEndElement() && xml.name() == DEVICE) && !xml.atEnd()) {
                            xml.readNext();
                            if (xml.isStartElement() && xml.name() == DEVICE_EPOCROOT) {
                                device.epocRoot = xml.readElementText();
                            } else if (xml.isStartElement() && xml.name() == DEVICE_TOOLSROOT) {
                                device.toolsRoot = xml.readElementText();
                            }
                        }
                        m_devices.append(device);
                    }
                }
            } else {
                xml.raiseError("Invalid 'devices' element version.");
            }
        }
    }
    devicesFile.close();
    if (xml.hasError()) {
        m_errorString = xml.errorString();
        return false;
    }

    return true;
}

bool S60Devices::detectQtForDevices()
{
    for (int i = 0; i < m_devices.size(); ++i) {
        QFile qtDll(QString("%1/epoc32/release/winscw/udeb/QtCore.dll").arg(m_devices[i].epocRoot));
        if (!qtDll.exists() || !qtDll.open(QIODevice::ReadOnly)) {
            m_devices[i].qt = QString();
            continue;
        }
        const QString indicator = "\\src\\corelib\\kernel\\qobject.h";
        int indicatorlength = indicator.length();
        QByteArray buffer;
        QByteArray previousBuffer;
        int index = -1;
        while (!qtDll.atEnd()) {
            buffer = qtDll.read(10000);
            index = buffer.indexOf(indicator.toLatin1());
            if (index >= 0)
                break;
            if (!qtDll.atEnd())
                qtDll.seek(qtDll.pos()-indicatorlength);
            previousBuffer = buffer;
        }
        int lastIndex = index;
        while (index >= 0 && buffer.at(index)) --index;
        if (index < 0) { // this is untested
        } else {
            index += 2; // the 0 and another byte for some reason
            m_devices[i].qt = QDir::toNativeSeparators(buffer.mid(index, lastIndex-index));
        }
        qtDll.close();
    }
    return true;
}

QString S60Devices::errorString() const
{
    return m_errorString;
}

QList<S60Devices::Device> S60Devices::devices() const
{
    return m_devices;
}

S60Devices::Device S60Devices::deviceForRoot(const QString &epocRoot) const
{
    foreach (const S60Devices::Device &i, m_devices) {
        if (i.epocRoot == epocRoot) {
            return i;
        }
    }
    return Device();
}