# Copyright (c) 2009, Joshua Wright
# All rights reserved.
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
# 
# * Redistributions of source code must retain the above copyright notice,
#   this list of conditions and the following disclaimer.
# * 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.
# * The name of the contributors may not 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 OWNER
# 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.

# Special thanks to Scott Weston and the pymissle project
# http://code.google.com/p/pymissile/

import usb

class DeviceDescriptor(object) :
    def __init__(self, vendor_id, product_id, interface_id) :
        self.vendor_id = vendor_id
        self.product_id = product_id
        self.interface_id = interface_id

    def getDevice(self) :
        """
        Return the device corresponding to the device descriptor if it is
        available on a USB bus.  Otherwise, return None.  Note that the
        returned device has yet to be claimed or opened.
        """
        buses = usb.busses()
        for bus in buses :
            for device in bus.devices :
                if device.idVendor == self.vendor_id :
                    if device.idProduct == self.product_id :
                        return device
        return None

class PlugUSBDevice(object) :
    
    PLUG_VENDOR_ID = 0x04d8
    PLUG_PRODUCT_ID = 0x000e
    PLUG_INTERFACE_ID = 0
    PLUG_BULK_EP_PACKETS = 0x81
    PLUG_BULK_EP_CONTROL = 0x01
    PLUG_BULK_IN_EP = 0x81
    PLUG_BULK_OUT_EP = 1
    PLUG_TIMEOUT = 200

    # 1st byte offset is the channel number, 11-26
    SET_CHAN  = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]

    def __init__(self) :
        self.device_descriptor = DeviceDescriptor(PlugUSBDevice.PLUG_VENDOR_ID,
                                              PlugUSBDevice.PLUG_PRODUCT_ID,
                                              PlugUSBDevice.PLUG_INTERFACE_ID)
        self.device = self.device_descriptor.getDevice()
        self.handle = None

    def open(self) :
        self.device = self.device_descriptor.getDevice()
        self.handle = self.device.open()
        self.handle.claimInterface(self.device_descriptor.interface_id)

    def close(self) :
        self.handle.releaseInterface()

    def setChannel(self, channel) :
        # Set the channel number
        if (channel > 26 or channel < 11):
                raise Exception, "Invalid channel " + str(channel)
        PlugUSBDevice.SET_CHAN[1] = channel
        self.handle.interruptWrite(PlugUSBDevice.PLUG_BULK_EP_CONTROL,
                        PlugUSBDevice.SET_CHAN, len(PlugUSBDevice.SET_CHAN))

    def getDataPacket(self, bytesToGet) :
        #print "DEBUG: Sending bulkRead"
        try:
            return self.handle.interruptRead(
                    PlugUSBDevice.PLUG_BULK_EP_PACKETS, bytesToGet)
        except usb.USBError, e:
            if e.args != ('No error',): # http://bugs.debian.org/476796
                raise e

plug = PlugUSBDevice()
plug.open()

plug.setChannel(26)

for i in range(1,10):
	packet = plug.getDataPacket(64)
	if packet:
           for j in range(0,len(packet)-1):
	    	print hex(packet[j]),
           print
plug.close()