import base64, pyftdi, sys, usb
from pyftdi.eeprom import FtdiEeprom
from pyftdi.misc import hexdump


DEFAULT_CONFIG = base64.b64decode(b"AAADBNB/ABCAyAgAAACgErIe0BwAAAAAAAAAAAAAAAAEAAAAYqd+A5/19nT0AQAAAAAAAAAAAAAAAAAAAAAAAIiIAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABWNqnJAQBqbK2IMAAAAAAAAAAAAURPUUE0RTAxAAAAABIDSQBLAEEATABPAEcASQBDAB4DUwBjAGEA\
bgBhAFEAdQBhAGQAIABTAFEANQAwABwDMQAwADAAMwAwADUAMAAwADAANQA0ADgAMgAAAAAAAAAAAAAAAAAAAAAAAABqPg==")


def main(args):
    dev = usb.core.find(idVendor=int(args.vendor,0), idProduct=int(args.product,0))
    if dev is None:
        print("ERROR: Device not found!", file=sys.stderr)
        exit(1)

    eeprom = FtdiEeprom()
    try:
        eeprom.open(dev)
        eeprom.dump_config()

        if args.backup is not None:
            args.backup.write(eeprom.data)
            return
        elif args.variant is None:
            print("ERROR: must select a variant!")
            exit(1)

        if args.init_with_default:
            eeprom.data = DEFAULT_CONFIG
            eeprom.set_serial_number("1003%03d0%06d" % (args.variant, random.randint(0,1000000)))
        else:
            eeprom.set_product_name("ScanaQuad SQ%d" % args.variant)
            if args.randomize_serial:
                eeprom.set_serial_number("1003%03d0%06d" % (args.variant, random.randint(0,1000000)))
            else:
                eeprom.set_serial_number(eeprom.serial[:4] + ("%03d"%args.variant) + eeprom.serial[6:])

        eeprom.commit(dry_run=args.dry_run)
        print(hexdump(eeprom.data))
        eeprom.dump_config()
    finally:
        eeprom.close()


if __name__ == '__main__':
    import argparse

    parser = argparse.ArgumentParser()
    parser.add_argument('--vendor', default="0x0403", help="USB vendor ID")
    parser.add_argument('--product', default="0x7fd0", help="USB product ID")

    grp = parser.add_mutually_exclusive_group(required=True)
    grp.add_argument('--backup', type=argparse.FileType('wb'), default=None, help="Back up the existing config (on the device) to this path. Inhibits any further actions of writing the EEPROM.")
    grp.add_argument('--variant', choices=[50,100,200], type=int, help="Variant to configure the device as")

    parser.add_argument('--init-with-default', default=False, action='store_true', help="Initialize entire EEPROM with default values (implies --randomize-serial, default off) (CAN BE DANGEROUS! USE ONLY FOR UNBRICKING!)")
    parser.add_argument('--randomize-serial', default=False, action='store_true', help="Randomize the device's serial number (default off)")
    parser.add_argument('--dry-run', dest='dry_run', default=True, action='store_true', help="Print result of action instead of actually writing to device (default on).")
    parser.add_argument('--no-dry-run', '--commit', dest='dry_run', default=True, action='store_false', help="Actually write to device (default is to dry run) (CAN BE DANGEROUS!)")
    args = parser.parse_args()
    main(args)