#!/usr/bin/env elixir

# Simple test to debug IFB_LLNUM field 2 parsing issue

# Add the lib path
Code.prepend_path("lib")

# Import required modules
alias DaProductApp.MercuryISO8583.Packagers.FieldPackagers.IFB_LLNUM

# Test data from user: "3747404231320090008000" should be "374740423132009" (15 digits)
# The user said consumed_bytes: 12, so let's simulate the raw data

# Let's assume the raw data has a length prefix of 15 (0x15) followed by BCD data
# For 15 digits, we need 8 bytes of BCD data (15 digits = 8 bytes since 2 digits per byte)

# Create test data: length prefix 0x15 + 8 bytes of BCD data for "374740423132009"
length_prefix = <<0x15>>  # 21 decimal, but should be 15
# BCD encoding of "374740423132009" (15 digits)
# 37 47 40 42 31 32 00 90 00 80 00 -> but we need to pack into 8 bytes
# Actually, let's calculate properly:
# "374740423132009" -> 15 digits
# BCD packed: 8 bytes (since 15 digits needs 8 bytes: 7*2 + 1 = 15)
bcd_data = <<0x37, 0x47, 0x40, 0x42, 0x31, 0x32, 0x00, 0x90>>  # This represents "374740423132009"

test_data = length_prefix <> bcd_data

IO.puts("Test data: #{inspect(test_data)}")
IO.puts("Test data hex: #{Base.encode16(test_data)}")

# Test unpacking
case IFB_LLNUM.unpack(%{}, test_data, 0, 2) do
  {:ok, {result, new_offset}} ->
    IO.puts("Success! Result: #{inspect(result)}")
    IO.puts("New offset: #{new_offset}")
    IO.puts("Parsed value: #{result.value}")
  {:error, reason} ->
    IO.puts("Error: #{reason}")
end

# Test with user's exact case: "3747404231320090008000" should be truncated to "374740423132009"
# This is 22 digits, BCD encoded as 11 bytes
length_prefix5 = <<0x22>>  # 22 decimal
bcd_data5 = <<0x37, 0x47, 0x40, 0x42, 0x31, 0x32, 0x00, 0x90, 0x00, 0x08, 0x00>>  # 11 bytes
test_data5 = length_prefix5 <> bcd_data5

IO.puts("Test data 5 (user's case): #{Base.encode16(test_data5)}")

case IFB_LLNUM.unpack(%{}, test_data5, 0, 2) do
  {:ok, {result, _new_offset}} ->
    IO.puts("Success! Result: #{inspect(result)}")
    IO.puts("Parsed value: #{result.value}")
    IO.puts("Length of parsed value: #{String.length(result.value)}")
    IO.puts("Should be truncated from 22 to 15 digits")
  {:error, reason} ->
    IO.puts("Error: #{reason}")
end