import os
import struct
import logging

# Logging setup
logger = logging.getLogger(__name__)

class Header:
    """Header data in file"""

    def __init__(self, file):
        header_fmt = '<4s2I2HI36s'
        header_size = struct.calcsize(header_fmt)

        try:
            header_data = file.read(header_size)
        except OSError as e:
            logger.critical("Could not read header")
            raise

        self.id, self.size, self.record_size, self.version, self.utc_start, self.reserve = struct.unpack(header_fmt, header_data)

        self.validate()

    def validate(self):
        # Validate header fields
        assert self.size == 56, "Invalid header size"
        assert self.id == b'SCID', "Invalid header id"

class Record:
    """Single record from file"""

    def __init__(self, file, record_size):
        self.record_size = record_size
        self.datetime = None  # Populate later
        # ...


def read_records(filename):

    with open(filename, 'rb') as file:

        header = Header(file)
        record_size = header.record_size

        while True:
            record = Record(file, record_size)

            yield (record.datetime, record.open, record.high,
                   record.low, record.close, record.num_trades,
                   record.total_volume, record.bid_volume,
                   record.ask_volume)

            # Keep reading records
            file.read(record_size)

# Reading Header Data
def read_header(filename):
    header_format = '<4s2I2HI36s'
    header_size = struct.calcsize(header_format)

    with open(filename, 'rb') as f:
        header_data = f.read(header_size)
        (
            header_id,
            header_size,
            record_size,
            version,
            unused1,
            utc_start,
            reserve
        ) = struct.unpack(header_format, header_data)

        # Validate header_id and header_size here if needed

        return header_id, header_size, record_size, version, unused1, utc_start, reserve

# Process real-time quote
def process_real_time_quote(record_data):
    # Process the real-time quote here
    pass

# Read real-time quotes
def read_real_time_quotes(filename, header_size, record_size):
    with open(filename, 'rb') as f:
        num_records = get_num_records(filename, header_size, record_size)
        record_start = num_records
        while True:
            seek_to_record(f, header_size, record_size, record_start)
            record_data = f.read(record_size)
            while len(record_data) == 0:
                record_data = f.read(record_size)
            process_real_time_quote(record_data)

# Sample usage
if __name__ == "__main__":
    filename = '/mnt/c/SierraChart/Data/ESU23-CME.scid'

    for (datetime, open, high, low, close, num_trades,
         total_volume, bid_volume, ask_volume) in read_records(filename):
        print(f"DateTime: {datetime}, Open: {open}, High: {high}, Low: {low}, Close: {close}, "
              f"NumTrades: {num_trades}, TotalVolume: {total_volume}, "
              f"BidVolume: {bid_volume}, AskVolume: {ask_volume}")