VISA

from iso8583sim.core.types import detect_network, CardNetwork

network = detect_network("4111111111111111")
assert network == CardNetwork.VISA

message.fields[62] = "01" + "0123456789"  # Example format

from iso8583sim.core.types import ISO8583Message, CardNetwork
from iso8583sim.core.builder import ISO8583Builder

message = ISO8583Message(
    mti="0100",
    network=CardNetwork.VISA,
    fields={
        0: "0100",
        2: "4111111111111111",      # VISA PAN
        3: "000000",                # Purchase
        4: "000000010000",          # $100.00
        7: "1225120000",            # Dec 25, 12:00:00
        11: "123456",               # STAN
        14: "2512",                 # Exp Dec 2025
        22: "051",                  # Chip, no PIN
        24: "100",                  # NII
        25: "00",                   # Normal transaction
        41: "TERM0001",
        42: "MERCHANT123456 ",
    }
)

builder = ISO8583Builder()
raw = builder.build(message)

from iso8583sim.demo import generate_emv_auth

emv_message = generate_emv_auth(
    pan="4111111111111111",
    amount=25000,
    cryptogram="1234567890ABCDEF",
)

# Field 55 contains EMV data
print(emv_message.fields.get(55))

from iso8583sim.core.validator import ISO8583Validator
from iso8583sim.core.types import CardNetwork

validator = ISO8583Validator()
message.network = CardNetwork.VISA

errors = validator.validate_message(message)
# Validates:
# - All VISA required fields present
# - PAN passes Luhn check
# - Field formats match VISA specs