from ctypes import *
b2 = CDLL("libpcie40.so")
dma_reset = b2.pcie40_b2dmabufferreset
dma_read = b2.pcie40_b2dmabufferread
DMASIZE = 0x2000

nErr = 0 
currentEventIndex = 0 

import os, itertools
from timeit import default_timer as timer

CRC16_XMODEM_TABLE = [
        0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
        0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
        0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
        0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
        0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
        0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
        0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
        0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
        0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
        0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
        0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
        0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
        0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
        0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
        0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
        0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
        0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
        0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
        0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
        0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
        0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
        0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
        0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
        0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
        0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
        0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
        0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
        0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
        0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
        0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
        0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
        0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0,
        ]


def _crc16(data, crc, table):
    """Calculate CRC16 using the given table.
    `data`      - data for calculating CRC, must be a string
    `crc`       - initial value
    `table`     - table for caclulating CRC (list of 256 integers)
    Return calculated value of CRC
    """
    for byte in data:
        byte1 = byte & 0xFF 
        byte2 = ( byte & 0xFF00 ) >> 8
        crc = ((crc<<8)&0xff00) ^ table[((crc>>8)&0xff)^byte2]
        crc = ((crc<<8)&0xff00) ^ table[((crc>>8)&0xff)^byte1]
    return crc & 0xffff

def decode_data( dataraw , data ):
    global currentEventIndex
    # Remove intermediate lines
    datamsb = list( itertools.islice( dataraw , currentEventIndex , None , 16 ) ) 
    datalsb = list( itertools.islice( dataraw , currentEventIndex + 8 , None , 16 ) )
    datamsb += list( itertools.islice( dataraw , 0 , currentEventIndex , 16 ) ) 
    datalsb += list( itertools.islice( dataraw , 8 , currentEventIndex + 8 , 16 ) )
    
    # Group in 32 bit words
    data += [ ( ( x & 0xFFFF ) | (  ( y & 0xFFFF ) << 16 ) ) for x, y in zip( datalsb, datamsb) ] 
    # Find beginning and end of event
    sizel = [ i for i, n in enumerate( data ) if n == data[0] ]
    if len( sizel ) > 1:
        size = sizel[ 1 ] + 2
        if size > 8:
            currentEventIndex = ( ( sizel[ 1 ] + 2 ) * 16 + currentEventIndex ) % DMASIZE  
            return size
    return 0

import socket
hname = socket.gethostname()

# Stop trigger (adapt this line to your system)
if ( hname == 'belle2daq.local' ):
    os.system( "ssh vme \"resetft -80\"" ) ### ADD this to suppress output >/dev/null 2>&1" )
else:   ### KEK 
    os.system( "ssh vme \"resetft -53\"" )

## temporisation of 2s
import time
time.sleep( 2 )

b2.ecs_open( 0 , 2 )
b2.ecs_open( 0 , 0 )
dma_reset( 0 )

# Send trigger (adapt this line to your system)
if ( hname == 'belle2daq.local' ):
    os.system( "ssh vme \"trigft -80 pulse 1 -1\"" ) ### ADD this to suppress output >/dev/null 2>&1" )
else:   ### KEK 
    os.system( "ssh vme \"trigft -53 pulse 1 -1\"" )

dataraw = ( c_int * DMASIZE )( *range( DMASIZE ) ) 
data = []
data_crc = []
size = 0

start = timer()

nEvt = 0 

for nev in range( 100000 ):
    if nev % 100 == 1: print "Event number {0}".format(nev)
    # Read DMA
    dma_read( 0 , dataraw ) 
    del data[:]

    size = decode_data( dataraw , data ) 

    if size <= 8: continue    
    del data_crc[:]

    nEvt = nEvt + 1 

    for i in range( size ):
        if ( i <= (size-3)) : 
            data_crc.append( ( data[ i ] & 0xFFFF0000 ) >> 16 )
            data_crc.append( ( data[ i ] & 0xFFFF ) ) 

    if ( data[size-1]&0xFFFF ) != ( _crc16( data_crc, 0xffff , CRC16_XMODEM_TABLE ) ):
        print 'Error in CRC comparison' 
        nErr = nErr + 1 

end = timer()

print 'number of errors = {0} out of {1} events'.format( nErr , nEvt ) 
print 'elapsed time = {0} s'.format( end - start )