#include "boo/inputdev/IHIDListener.hpp"
#include "boo/inputdev/DeviceFinder.hpp"
#include <CoreFoundation/CoreFoundation.h>
#include <IOKit/hid/IOHIDLib.h>
#include <IOKit/hid/IOHIDDevicePlugin.h>
#include <IOKit/hid/IOHIDKeys.h>
#include <IOKit/IOKitLib.h>
#include <IOKit/usb/IOUSBLib.h>
#include <IOKit/IOCFPlugIn.h>
#include "IOKitPointer.hpp"
#include "CFPointer.hpp"

namespace boo
{

/*
 * Reference: http://oroboro.com/usb-serial-number-osx/
 */

static bool getUSBStringDescriptor(const IUnknownPointer<IOUSBDeviceInterface182>& usbDevice, UInt8 idx, char* out)
{
    UInt16 buffer[128];
    
    // wow... we're actually forced to make hard coded bus requests. Its like
    // hard disk programming in the 80's!
    IOUSBDevRequest request;
    
    request.bmRequestType = USBmakebmRequestType(kUSBIn,
                                                 kUSBStandard,
                                                 kUSBDevice);
    request.bRequest = kUSBRqGetDescriptor;
    request.wValue = (kUSBStringDesc << 8) | idx;
    request.wIndex = 0x409; // english
    request.wLength = sizeof(buffer);
    request.pData = buffer;
    
    kern_return_t err = usbDevice->DeviceRequest(usbDevice.storage(), &request);
    if (err != 0)
    {
        // the request failed... fairly uncommon for the USB disk driver, but not
        // so uncommon for other devices. This can also be less reliable if your
        // disk is mounted through an external USB hub. At this level we actually
        // have to worry about hardware issues like this.
        return false;
    }
    
    // we're mallocing this string just as an example. But you probably will want
    // to do something smarter, like pre-allocated buffers in the info class, or
    // use a string class.
    if (request.wLenDone == 0)
        return false;

    unsigned count = (request.wLenDone - 1) / 2;
    unsigned i;
    for (i=0 ; i<count ; ++i)
        out[i] = buffer[i+1];
    out[i] = '\0';
    
    return true;
}

class HIDListenerIOKit : public IHIDListener
{
    DeviceFinder& m_finder;
    
    CFRunLoopRef m_listenerRunLoop;
    IONotificationPortRef m_llPort;
    IOObjectPointer<io_iterator_t> m_llAddNotif, m_llRemoveNotif;
    IOObjectPointer<io_iterator_t> m_hidAddNotif, m_hidRemoveNotif;
    bool m_scanningEnabled;
    
    static void devicesConnectedUSBLL(HIDListenerIOKit* listener,
                                      io_iterator_t      iterator)
    {
        while (IOObjectPointer<io_service_t> obj = IOIteratorNext(iterator))
        {
            io_string_t devPath;
            if (IORegistryEntryGetPath(obj.get(), kIOServicePlane, devPath) != 0)
                continue;

            if (!listener->m_scanningEnabled ||
                listener->m_finder._hasToken(devPath))
                continue;
            
            UInt16 vid, pid;
            char vstr[128] = {0};
            char pstr[128] = {0};
            {
                IOCFPluginPointer devServ;
                SInt32 score;
                IOReturn err;
                err = IOCreatePlugInInterfaceForService(obj.get(), kIOUSBDeviceUserClientTypeID, kIOCFPlugInInterfaceID, &devServ, &score);
                if (err != kIOReturnSuccess)
                {
                    fprintf(stderr, "unable to open IOKit plugin interface\n");
                    continue;
                }

                IUnknownPointer<IOUSBDeviceInterface182> dev;
                err = devServ.As(&dev, kIOUSBDeviceInterfaceID182);
                if (err != kIOReturnSuccess)
                {
                    fprintf(stderr, "unable to open IOKit device interface\n");
                    continue;
                }

                dev->GetDeviceVendor(dev.storage(), &vid);
                dev->GetDeviceProduct(dev.storage(), &pid);

                UInt8 vstridx, pstridx;
                dev->USBGetManufacturerStringIndex(dev.storage(), &vstridx);
                dev->USBGetProductStringIndex(dev.storage(), &pstridx);

                getUSBStringDescriptor(dev, vstridx, vstr);
                getUSBStringDescriptor(dev, pstridx, pstr);
            }

            listener->m_finder._insertToken(std::make_unique<DeviceToken>(DeviceType::USB,
                                            vid, pid, vstr, pstr, devPath));

            //printf("ADDED %08X %s\n", obj, devPath);
        }
    }
    
    static void devicesDisconnectedUSBLL(HIDListenerIOKit* listener,
                                         io_iterator_t      iterator)
    {
        if (CFRunLoopGetCurrent() != listener->m_listenerRunLoop)
        {
            CFRunLoopPerformBlock(listener->m_listenerRunLoop, kCFRunLoopDefaultMode, ^{
                devicesDisconnectedUSBLL(listener, iterator);
            });
            CFRunLoopWakeUp(listener->m_listenerRunLoop);
            return;
        }
        while (IOObjectPointer<io_service_t> obj = IOIteratorNext(iterator))
        {
            io_string_t devPath;
            if (IORegistryEntryGetPath(obj.get(), kIOServicePlane, devPath) != 0)
                continue;
            listener->m_finder._removeToken(devPath);
            //printf("REMOVED %08X %s\n", obj, devPath);
        }
    }

    static void devicesConnectedHID(HIDListenerIOKit* listener,
                                    io_iterator_t     iterator)
    {
        while (IOObjectPointer<io_service_t> obj = IOIteratorNext(iterator))
        {
            io_string_t devPath;
            if (IORegistryEntryGetPath(obj.get(), kIOServicePlane, devPath) != 0)
                continue;

            if (!listener->m_scanningEnabled ||
                listener->m_finder._hasToken(devPath))
                continue;

            unsigned vidv, pidv;
            char vstr[128] = {0};
            char pstr[128] = {0};
            {
                IOCFPluginPointer devServ;
                SInt32 score;
                IOReturn err;
                err = IOCreatePlugInInterfaceForService(obj.get(), kIOHIDDeviceTypeID, kIOCFPlugInInterfaceID, &devServ, &score);
                if (err != kIOReturnSuccess)
                {
                    fprintf(stderr, "unable to open IOKit plugin interface\n");
                    continue;
                }

                IUnknownPointer<IOHIDDeviceDeviceInterface> dev;
                err = devServ.As(&dev, kIOHIDDeviceDeviceInterfaceID);
                if (err != kIOReturnSuccess)
                {
                    fprintf(stderr, "unable to open IOKit device interface\n");
                    continue;
                }

                /* Game controllers only */
                CFPointer<CFNumberRef> usagePage;
                dev->getProperty(dev.storage(), CFSTR(kIOHIDPrimaryUsagePageKey), &usagePage);
                CFPointer<CFNumberRef> usage;
                dev->getProperty(dev.storage(), CFSTR(kIOHIDPrimaryUsageKey), &usage);
                int usagePageV, usageV;
                CFNumberGetValue(usagePage.get(), kCFNumberIntType, &usagePageV);
                CFNumberGetValue(usage.get(), kCFNumberIntType, &usageV);
                if (usagePageV == kHIDPage_GenericDesktop)
                {
                    if (usageV != kHIDUsage_GD_Joystick && usageV != kHIDUsage_GD_GamePad)
                        continue;
                }
                else
                {
                    continue;
                }

                CFPointer<CFNumberRef> vid, pid;
                dev->getProperty(dev.storage(), CFSTR(kIOHIDVendorIDKey), &vid);
                dev->getProperty(dev.storage(), CFSTR(kIOHIDProductIDKey), &pid);
                CFNumberGetValue(vid.get(), kCFNumberIntType, &vidv);
                CFNumberGetValue(pid.get(), kCFNumberIntType, &pidv);

                CFPointer<CFStringRef> vstridx, pstridx;
                dev->getProperty(dev.storage(), CFSTR(kIOHIDManufacturerKey), &vstridx);
                dev->getProperty(dev.storage(), CFSTR(kIOHIDProductKey), &pstridx);

                if (vstridx)
                    CFStringGetCString(vstridx.get(), vstr, 128, kCFStringEncodingUTF8);
                if (pstridx)
                    CFStringGetCString(pstridx.get(), pstr, 128, kCFStringEncodingUTF8);
            }

            listener->m_finder._insertToken(std::make_unique<DeviceToken>(DeviceType::HID,
                                            vidv, pidv, vstr, pstr, devPath));

            //printf("ADDED %08X %s\n", obj, devPath);
        }
    }

    static void devicesDisconnectedHID(HIDListenerIOKit* listener,
                                       io_iterator_t     iterator)
    {
        if (CFRunLoopGetCurrent() != listener->m_listenerRunLoop)
        {
            CFRunLoopPerformBlock(listener->m_listenerRunLoop, kCFRunLoopDefaultMode, ^{
                devicesDisconnectedHID(listener, iterator);
            });
            CFRunLoopWakeUp(listener->m_listenerRunLoop);
            return;
        }
        while (IOObjectPointer<io_service_t> obj = IOIteratorNext(iterator))
        {
            io_string_t devPath;
            if (IORegistryEntryGetPath(obj.get(), kIOServicePlane, devPath) != 0)
                continue;
            listener->m_finder._removeToken(devPath);
            //printf("REMOVED %08X %s\n", obj, devPath);
        }
    }

public:
    HIDListenerIOKit(DeviceFinder& finder)
    : m_finder(finder)
    {
        m_listenerRunLoop = CFRunLoopGetMain();
        m_llPort = IONotificationPortCreate(kIOMasterPortDefault);
        CFRunLoopSourceRef rlSrc = IONotificationPortGetRunLoopSource(m_llPort);
        CFRunLoopAddSource(m_listenerRunLoop, rlSrc, kCFRunLoopDefaultMode);
        m_scanningEnabled = true;

        /* Register HID Matcher */
        {
            CFMutableDictionaryRef matchDict = IOServiceMatching("IOHIDDevice");
            CFRetain(matchDict);

            kern_return_t hidRet =
            IOServiceAddMatchingNotification(m_llPort, kIOMatchedNotification, matchDict,
                                             (IOServiceMatchingCallback)devicesConnectedHID, this, &m_hidAddNotif);
            if (hidRet == kIOReturnSuccess)
                devicesConnectedHID(this, m_hidAddNotif.get());

            hidRet =
            IOServiceAddMatchingNotification(m_llPort, kIOTerminatedNotification, matchDict,
                                             (IOServiceMatchingCallback)devicesDisconnectedHID, this, &m_hidRemoveNotif);
            if (hidRet == kIOReturnSuccess)
                devicesDisconnectedHID(this, m_hidRemoveNotif.get());
        }

        /* Register Low-Level USB Matcher */
        {
            CFMutableDictionaryRef matchDict = IOServiceMatching(kIOUSBDeviceClassName);
            CFRetain(matchDict);

            kern_return_t llRet =
            IOServiceAddMatchingNotification(m_llPort, kIOMatchedNotification, matchDict,
                                             (IOServiceMatchingCallback)devicesConnectedUSBLL, this, &m_llAddNotif);
            if (llRet == kIOReturnSuccess)
                devicesConnectedUSBLL(this, m_llAddNotif.get());

            llRet =
            IOServiceAddMatchingNotification(m_llPort, kIOTerminatedNotification, matchDict,
                                             (IOServiceMatchingCallback)devicesDisconnectedUSBLL, this, &m_llRemoveNotif);
            if (llRet == kIOReturnSuccess)
                devicesDisconnectedUSBLL(this, m_llRemoveNotif.get());
        }
        
        m_scanningEnabled = false;
    }
    
    ~HIDListenerIOKit()
    {
        //CFRunLoopRemoveSource(m_listenerRunLoop, IONotificationPortGetRunLoopSource(m_llPort), kCFRunLoopDefaultMode);
        IONotificationPortDestroy(m_llPort);
    }
    
    /* Automatic device scanning */
    bool startScanning()
    {
        m_scanningEnabled = true;
        return true;
    }
    bool stopScanning()
    {
        m_scanningEnabled = false;
        return true;
    }
    
    /* Manual device scanning */
    bool scanNow()
    {
        IOObjectPointer<io_iterator_t> iter;
        if (IOServiceGetMatchingServices(kIOMasterPortDefault,
                                         IOServiceMatching(kIOUSBDeviceClassName), &iter) == kIOReturnSuccess)
        {
            devicesConnectedUSBLL(this, iter.get());
        }
        return true;
    }
    
};

std::unique_ptr<IHIDListener> IHIDListenerNew(DeviceFinder& finder)
{
    return std::make_unique<HIDListenerIOKit>(finder);
}

}