fix login issue*

docs/PACKET_LOGGING.md

@@ -0,0 +1,92 @@
+# Packet Logging System
+
+## Overview
+
+Comprehensive packet logging system for debugging the MapleStory protocol, matching the Java version's logging format.
+
+## Features
+
+- **Direction Indicators**: `[client]` for incoming packets, `[loopback]` for outgoing packets
+- **Opcode Names**: Human-readable packet names (e.g., `CP_CheckPassword`, `LP_ServerList`)
+- **Opcode Values**: Both decimal and hexadecimal (e.g., `2 / 0x02`)
+- **Raw Hex Data**: Space-separated hex bytes
+- **ASCII Text**: Printable characters with dots for non-printable
+- **Context Information**: IP address, server type, packet size
+
+## Configuration
+
+Enable/disable packet logging in `config/config.exs`:
+
+```elixir
+config :odinsea, :features,
+  log_packet: true  # Set to false to disable
+```
+
+## Example Output
+
+```
+[client] [CP_PermissionRequest] 1 / 0x01
+[Data] 01 00 07 70 00 04 00
+[Text] ...p...
+[Context] IP=127.0.0.1 Server=login Size=7 bytes
+
+[loopback] [RSA_KEY] 32 / 0x20
+[Data] 20 00
+[Text]  .
+[Context] IP=127.0.0.1 Server=login Size=2 bytes
+```
+
+## Implementation Details
+
+### Files Added
+
+- `lib/odinsea/net/packet_logger.ex` - Main packet logging module
+
+### Files Modified
+
+- `lib/odinsea/login/client.ex` - Added packet logging for incoming client packets
+- `lib/odinsea/login/handler.ex` - Added packet logging for outgoing server packets
+- `lib/odinsea/net/processor.ex` - Fixed handler function name mismatches
+
+### Key Functions
+
+#### `PacketLogger.log_client_packet/3`
+Logs incoming packets from the client with opcode, data, and context.
+
+#### `PacketLogger.log_server_packet/3`
+Logs outgoing packets to the client with opcode, data, and context.
+
+#### `PacketLogger.log_raw_packet/4`
+Logs raw packets (e.g., hello handshake) that don't follow the standard opcode format.
+
+## Opcode Name Resolution
+
+The logger includes comprehensive opcode name mappings for:
+
+- **Client Opcodes** (CP_*): Login, authentication, character management, gameplay, etc.
+- **Server Opcodes** (LP_*): Responses, server lists, character data, game state, etc.
+
+Unknown opcodes are displayed as `UNKNOWN`.
+
+## Usage Tips
+
+1. **Enable during development**: Keep `log_packet: true` to debug connection issues
+2. **Disable in production**: Set `log_packet: false` to reduce log noise and improve performance
+3. **Compare with Java logs**: Use this to verify protocol compatibility with the Java server
+4. **Debug handshake issues**: Check that HELLO packet is sent before CP_PermissionRequest
+
+## Debugging Login Issues
+
+The login sequence should look like this:
+
+1. **[loopback] HELLO** - Server sends handshake with IVs
+2. **[client] CP_PermissionRequest** - Client sends version check
+3. **[loopback] RSA_KEY / LOGIN_AUTH** - Server sends RSA key and login background
+4. **[client] CP_CheckPassword** - Client sends login credentials
+5. **[loopback] LOGIN_STATUS** - Server sends authentication result
+
+If packets are missing or out of order, check:
+- Network connectivity
+- Client version compatibility (v342)
+- Opcode mappings in `opcodes.ex`
+- Handler routing in `processor.ex`