import struct

def __indexOfOne(data, tokens, offset):
	for i in xrange(offset, len(data)):
		if data[i] in tokens:
			return i
	return -1

def rawComparer(data1, data2, comparer):
    """
    c - char
    s - string
    i - int (1, 2, 4, 8)
    u - unsigned int (1, 2, 4, 8)
    f - double (4, 8)
    """
    typeIds = [ 's', 'u', 'c', 'i', 'f', 'x' ]
    pyBinMap = { 
        ('u', 1): 'B', ('u', 2): 'H', ('u', 4):'L', ('u', 8):'Q',
        ('i', 1): 'b', ('i', 2): 'h', ('i', 4):'l', ('i', 8):'q',
        ('f', 4): 'f', ('f', 8): 'd'
    }

    p = i = 0
    while i < len(comparer):
        nextIdx = __indexOfOne(comparer, typeIds, i + 1)
        if (nextIdx < 0): nextIdx = len(comparer)
        
        format = None
        length = 1 if (i + 1) == nextIdx else int(comparer[i+1:nextIdx])        
        if comparer[i] == 's':
            format = str(length) + 's'
        elif comparer[i] == 'c':
            format = 'c'
        elif (comparer[i], length) in pyBinMap:
            format = pyBinMap[(comparer[i], length)]            

        if format != None:
            d1 = struct.unpack(format, data1[p:p+length])[0]
            d2 = struct.unpack(format, data2[p:p+length])[0]
            
            if d1 < d2:
                return -1
            elif d1 > d2:
                return 1            

        p += length
        i = nextIdx
    return 0

if __name__ == '__main__':
    data1 = struct.pack('4sLch', 'test', 10, 'A', -3)
    data2 = struct.pack('4sLch', 'test', 10, 'A', -3)    
    print 'Equal (test 10 A -3)', rawComparer(data1, data2, 's4u4ci2')
    
    data1 = struct.pack('4sLch', 'test', 10, 'A', 1)
    data2 = struct.pack('4sLch', 'test', 10, 'A', 0)    
    print '(test 10 A 1) > (test 10 A 0)', rawComparer(data1, data2, 's4u4ci2')
    
    data1 = struct.pack('4sLch', 'test', 10, 'A', 0)
    data2 = struct.pack('4sLch', 'test', 10, 'A', 1)    
    print '(test 10 A 0) < (test 10 A 1)', rawComparer(data1, data2, 's4u4ci2')  
    
    data1 = struct.pack('4sLch', 'test', 10, 'B', 0)
    data2 = struct.pack('4sLch', 'test', 10, 'A', 0)    
    print '(test 10 B 1) > (test 10 A 0)', rawComparer(data1, data2, 's4u4ci2')
    
    data1 = struct.pack('4sLch', 'test', 10, 'A', 0)
    data2 = struct.pack('4sLch', 'test', 10, 'B', 0)    
    print '(test 10 A 0) < (test 10 B 0)', rawComparer(data1, data2, 's4u4ci2')
    
    data1 = struct.pack('4sLch', 'test', 10, 'A', 0)
    data2 = struct.pack('4sLch', 'best', 10, 'A', 0)    
    print '(test 10 B 0) > (best 10 A 0)', rawComparer(data1, data2, 's4u4ci2')
    
    data1 = struct.pack('4sLch', 'best', 10, 'A', 0)
    data2 = struct.pack('4sLch', 'test', 10, 'A', 0)    
    print '(best 10 A 0) < (test 10 B 1)', rawComparer(data1, data2, 's4u4ci2')