Refactored a few things from main into modules

server/src/http/mod.rs

@@ -25,8 +25,31 @@ use poem::{Route, get, post};
 use poem_openapi::OpenApiService;
 use project::ProjectApi;
 use settings::SettingsApi;
+use std::path::{Path, PathBuf};
 use std::sync::Arc;
 
+const DEFAULT_PORT: u16 = 3001;
+
+pub fn parse_port(value: Option<String>) -> u16 {
+    value
+        .and_then(|v| v.parse::<u16>().ok())
+        .unwrap_or(DEFAULT_PORT)
+}
+
+pub fn resolve_port() -> u16 {
+    parse_port(std::env::var("STORYKIT_PORT").ok())
+}
+
+pub fn write_port_file(dir: &Path, port: u16) -> Option<PathBuf> {
+    let path = dir.join(".story_kit_port");
+    std::fs::write(&path, port.to_string()).ok()?;
+    Some(path)
+}
+
+pub fn remove_port_file(path: &Path) {
+    let _ = std::fs::remove_file(path);
+}
+
 pub fn build_routes(ctx: AppContext) -> impl poem::Endpoint {
     let ctx_arc = std::sync::Arc::new(ctx);
 
@@ -93,3 +116,34 @@ pub fn build_openapi_service(ctx: Arc<AppContext>) -> (ApiService, ApiService) {
 
     (api_service, docs_service)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn parse_port_defaults_to_3001() {
+        assert_eq!(parse_port(None), 3001);
+    }
+
+    #[test]
+    fn parse_port_reads_valid_value() {
+        assert_eq!(parse_port(Some("4200".to_string())), 4200);
+    }
+
+    #[test]
+    fn parse_port_ignores_invalid_value() {
+        assert_eq!(parse_port(Some("not_a_number".to_string())), 3001);
+    }
+
+    #[test]
+    fn write_and_remove_port_file() {
+        let tmp = tempfile::tempdir().unwrap();
+
+        let path = write_port_file(tmp.path(), 4567).expect("should write port file");
+        assert_eq!(std::fs::read_to_string(&path).unwrap(), "4567");
+
+        remove_port_file(&path);
+        assert!(!path.exists());
+    }
+}