# Debug script to trace crypto operations with CORRECT IV
# Run with: cd /home/ra/odinsea-elixir && elixir test/debug_crypto2.exs

Code.require_file("lib/odinsea/util/bit_tools.ex", ".")
Code.require_file("lib/odinsea/net/cipher/ig_cipher.ex", ".")
Code.require_file("lib/odinsea/net/cipher/aes_cipher.ex", ".")
Code.require_file("lib/odinsea/net/cipher/shanda_cipher.ex", ".")

alias Odinsea.Net.Cipher.{IGCipher, AESCipher, ShandaCipher}

import Bitwise

IO.puts("=== Debugging Crypto (Corrected IV) ===\n")

# From the hello packet sent by server:
# [Data] 0E 00 70 00 01 00 34 9A 0F 0C A8 BC 0D B3 E6 07
# Server sends: recv_iv=34 9A 0F 0C, send_iv=A8 BC 0D B3
#
# Client SWAPS these:
# Client's send_iv = server's recv_iv = 34 9A 0F 0C
# Client's recv_iv = server's send_iv = A8 BC 0D B3
#
# Client encrypts with its send_iv (34 9A 0F 0C)
# Server must decrypt with its recv_iv = 34 9A 0F 0C

server_send_iv = <<0xA8, 0xBC, 0x0D, 0xB3>>  # Server sends this, client uses as recv
server_recv_iv = <<0x34, 0x9A, 0x0F, 0x0C>>  # Server sends this, client uses as send

IO.puts("Server perspective:")
IO.puts("  server_send_iv: #{Base.encode16(server_send_iv)}")
IO.puts("  server_recv_iv: #{Base.encode16(server_recv_iv)}")

IO.puts("\nClient perspective (after swapping):")
IO.puts("  client_send_iv = server_recv_iv: #{Base.encode16(server_recv_iv)}")
IO.puts("  client_recv_iv = server_send_iv: #{Base.encode16(server_send_iv)}")

# First encrypted packet from client:
# [Data] 7C A8 7B A8 BF 0A CD DE C7 71 AC
packet = <<0x7C, 0xA8, 0x7B, 0xA8, 0xBF, 0x0A, 0xCD, 0xDE, 0xC7, 0x71, 0xAC>>

IO.puts("\nRaw packet: #{Base.encode16(packet)}")

# Server decrypts with server_recv_iv
recv_iv = server_recv_iv
IO.puts("Server decrypts with recv_iv: #{Base.encode16(recv_iv)}")

# Extract header
<<raw_seq::little-16, raw_len::little-16, payload::binary>> = packet
IO.puts("\nHeader:")
IO.puts("  raw_seq: 0x#{Integer.to_string(raw_seq, 16)} (#{raw_seq})")
IO.puts("  raw_len: 0x#{Integer.to_string(raw_len, 16)} (#{raw_len})")
IO.puts("  payload: #{Base.encode16(payload)} (#{byte_size(payload)} bytes)")

# Validate header
<<_r0, _r1, r2, r3>> = recv_iv
enc_version = 112
seq_base = ((r2 &&& 0xFF) ||| ((r3 <<< 8) &&& 0xFF00)) &&& 0xffff
calculated_version = bxor(raw_seq &&& 0xFFFF, seq_base)

IO.puts("\nHeader validation:")
IO.puts("  r2: 0x#{Integer.to_string(r2, 16)} (#{r2})")
IO.puts("  r3: 0x#{Integer.to_string(r3, 16)} (#{r3})")
IO.puts("  seq_base: 0x#{Integer.to_string(seq_base, 16)} (#{seq_base})")
IO.puts("  raw_seq ^ seq_base: #{calculated_version}")
IO.puts("  expected_version: #{enc_version}")
IO.puts("  valid: #{calculated_version == enc_version}")

# Get packet length
packet_len = bxor(raw_seq, raw_len) &&& 0xFFFF
IO.puts("\nPacket length: #{packet_len}")

# Decrypt with AES
IO.puts("\n=== AES Decryption ===")
IO.puts("Input: #{Base.encode16(payload)}")
aes_decrypted = AESCipher.crypt(payload, recv_iv)
IO.puts("After AES: #{Base.encode16(aes_decrypted)}")

# Decrypt with Shanda
IO.puts("\n=== Shanda Decryption ===")
shanda_decrypted = ShandaCipher.decrypt(aes_decrypted)
IO.puts("After Shanda: #{Base.encode16(shanda_decrypted)}")

# Expected opcode 0x01 = 1
if byte_size(shanda_decrypted) >= 2 do
  <<opcode::little-16, rest::binary>> = shanda_decrypted
  IO.puts("\n=== Result ===")
  IO.puts("Opcode: 0x#{Integer.to_string(opcode, 16)} (#{opcode})")
  IO.puts("Rest: #{Base.encode16(rest)}")
  
  if opcode == 1 do
    IO.puts("\n✓ SUCCESS! This is CP_PermissionRequest (0x01)")
  else
    IO.puts("\n✗ FAILED! Expected opcode 0x01, got 0x#{Integer.to_string(opcode, 16)}")
  end
end

# Update IV
new_recv_iv = IGCipher.inno_hash(recv_iv)
IO.puts("\nUpdated recv_iv: #{Base.encode16(new_recv_iv)}")

IO.puts("\n=== Done ===")