class BitStream:
    def __init__(self, data: list = []):
        self.bits_used = 0
        self.read_offset = 0
        self.data = data
    
    def write(self, c_bytes): # ?bytes_to_write
        bytes_to_write = len(c_bytes)
        if not len(c_bytes):
            return
        
        self.write_bits(c_bytes, bytes_to_write << 3, True)
    
    def read(self, bytes_to_read: int):
        bits_to_read = bytes_to_read << 3
        
        if self.read_offset & 7 == 0:
            if self.read_offset + bits_to_read > self.bits_used:
                return False
            
            read_offset_bytes = self.read_offset >> 3
            data = self.data[read_offset_bytes:read_offset_bytes + bytes_to_read]
            
            self.read_offset += bits_to_read
            return data
        return self.read_bits(bits_to_read)
    
    def read_bits(self, bits_to_read: int, align_right: bool = False):
        if bits_to_read <= 0:
            return False
        
        if self.read_offset + bits_to_read > self.bits_used:
            return False
        
        offset = 0
        bits_read_offset_mod8 = self.read_offset & 7
        
    
    def write_bits(self, c_bytes, bits_to_write: int, align_right: bool = False):
        if not bits_to_write:
            return
        
        offset = 0
        bits_used_mod8 = self.bits_used & 7
        
        while bits_to_write:
            byte = c_bytes[offset]
            
            if bits_to_write < 8 and align_right:
                byte <<= 8 - bits_to_write
            
            if bits_used_mod8 == 0:
                self.data[self.bits_used >> 3] = byte
            else:
                self.data[self.bits_used >> 3] |= byte >> bits_used_mod8
                if 8 - bits_used_mod8 < 8 and 8 - bits_used_mod8 < bits_to_write:
                    self.data[(self.bits_used >> 3) + 1] = byte << (8 - bits_used_mod8)
            
            if bits_to_write >= 8:
                self.bits_used += 8
            else:
                self.bits_used += bits_to_write
                
            bits_to_write -= 8
            
            offset += 1