From 355d0debda453ebd85fbbd1c4da681b0a9b3e8fe Mon Sep 17 00:00:00 2001
From: Anders Olsson <anders.e.olsson@gmail.com>
Date: Mon, 25 May 2026 11:23:57 +0200
Subject: [PATCH] feat(protocol): ServerConfig + ConfigError + RpcErrorCode

---
 crates/xy-protocol/src/config.rs | 20 +++++++++++++++++
 crates/xy-protocol/src/error.rs  | 37 ++++++++++++++++++++++++++++++++
 crates/xy-protocol/src/lib.rs    |  4 +++-
 3 files changed, 60 insertions(+), 1 deletion(-)
 create mode 100644 crates/xy-protocol/src/error.rs

diff --git a/crates/xy-protocol/src/config.rs b/crates/xy-protocol/src/config.rs
index f520339..a4cab81 100644
--- a/crates/xy-protocol/src/config.rs
+++ b/crates/xy-protocol/src/config.rs
@@ -68,6 +68,26 @@ impl Default for StopConfig {
     }
 }
 
+use std::collections::BTreeMap;
+use std::path::PathBuf;
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct ServerConfig {
+    pub name: String,
+    pub command: PathBuf,
+    #[serde(default)]
+    pub args: Vec<String>,
+    pub port: u16,
+    #[serde(default)]
+    pub env: BTreeMap<String, String>,
+    #[serde(default)]
+    pub working_dir: Option<PathBuf>,
+    #[serde(default)]
+    pub restart: RestartConfig,
+    #[serde(default)]
+    pub stop: StopConfig,
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/crates/xy-protocol/src/error.rs b/crates/xy-protocol/src/error.rs
new file mode 100644
index 0000000..4a0ffba
--- /dev/null
+++ b/crates/xy-protocol/src/error.rs
@@ -0,0 +1,37 @@
+use std::path::PathBuf;
+use thiserror::Error;
+
+#[derive(Debug, Error)]
+pub enum ConfigError {
+    #[error("failed to read {path}: {source}")]
+    Io { path: PathBuf, #[source] source: std::io::Error },
+
+    #[error("failed to parse KDL in {path}: {message}")]
+    Parse { path: PathBuf, message: String },
+
+    #[error("missing required field `{field}` in {path}")]
+    MissingField { path: PathBuf, field: &'static str },
+
+    #[error("invalid value for `{field}` in {path}: {message}")]
+    InvalidValue { path: PathBuf, field: &'static str, message: String },
+
+    #[error("duplicate port {port} declared by both `{name_a}` and `{name_b}`")]
+    DuplicatePort { name_a: String, name_b: String, port: u16 },
+
+    #[error("server name `{name}` contains invalid characters (allowed: a-z, 0-9, '-', '_')")]
+    InvalidName { name: String },
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum RpcErrorCode {
+    ServerNotFound = -32001,
+    PortConflict = -32002,
+    ConfigInvalid = -32003,
+    AlreadyRunning = -32004,
+    NotRunning = -32005,
+    SpawnFailed = -32006,
+}
+
+impl RpcErrorCode {
+    pub fn as_i32(self) -> i32 { self as i32 }
+}
diff --git a/crates/xy-protocol/src/lib.rs b/crates/xy-protocol/src/lib.rs
index 246cdfd..6c933ad 100644
--- a/crates/xy-protocol/src/lib.rs
+++ b/crates/xy-protocol/src/lib.rs
@@ -1,7 +1,9 @@
 //! Wire types and config schema shared between the xy daemon and CLI.
 
 pub mod config;
+pub mod error;
 pub mod state;
 
-pub use config::{RestartConfig, RestartPolicy, StopConfig};
+pub use config::{RestartConfig, RestartPolicy, ServerConfig, StopConfig};
+pub use error::{ConfigError, RpcErrorCode};
 pub use state::ServerState;