Support non interactive mode and model selection

src/settings.rs

@@ -0,0 +1,107 @@
+//! User settings persistence.
+//!
+//! Stores user preferences like selected model in ~/.near-agent/settings.json.
+
+use std::path::PathBuf;
+
+use serde::{Deserialize, Serialize};
+
+/// User settings persisted to disk.
+#[derive(Debug, Clone, Serialize, Deserialize, Default)]
+pub struct Settings {
+    /// Currently selected model.
+    #[serde(default)]
+    pub selected_model: Option<String>,
+}
+
+impl Settings {
+    /// Get the default settings file path (~/.near-agent/settings.json).
+    pub fn default_path() -> PathBuf {
+        dirs::home_dir()
+            .unwrap_or_else(|| PathBuf::from("."))
+            .join(".near-agent")
+            .join("settings.json")
+    }
+
+    /// Load settings from disk, returning default if not found.
+    pub fn load() -> Self {
+        Self::load_from(&Self::default_path())
+    }
+
+    /// Load settings from a specific path.
+    pub fn load_from(path: &PathBuf) -> Self {
+        match std::fs::read_to_string(path) {
+            Ok(data) => serde_json::from_str(&data).unwrap_or_default(),
+            Err(_) => Self::default(),
+        }
+    }
+
+    /// Save settings to disk.
+    pub fn save(&self) -> std::io::Result<()> {
+        self.save_to(&Self::default_path())
+    }
+
+    /// Save settings to a specific path.
+    pub fn save_to(&self, path: &PathBuf) -> std::io::Result<()> {
+        // Ensure parent directory exists
+        if let Some(parent) = path.parent() {
+            std::fs::create_dir_all(parent)?;
+        }
+
+        let json = serde_json::to_string_pretty(self)
+            .map_err(|e| std::io::Error::new(std::io::ErrorKind::InvalidData, e.to_string()))?;
+
+        std::fs::write(path, json)
+    }
+
+    /// Get the selected model, falling back to the provided default.
+    pub fn model_or(&self, default: &str) -> String {
+        self.selected_model
+            .clone()
+            .unwrap_or_else(|| default.to_string())
+    }
+
+    /// Set the selected model and save.
+    pub fn set_model(&mut self, model: &str) -> std::io::Result<()> {
+        self.selected_model = Some(model.to_string());
+        self.save()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use tempfile::tempdir;
+
+    #[test]
+    fn test_settings_save_load() {
+        let dir = tempdir().unwrap();
+        let path = dir.path().join("settings.json");
+
+        let settings = Settings {
+            selected_model: Some("claude-3-5-sonnet-20241022".to_string()),
+        };
+
+        settings.save_to(&path).unwrap();
+
+        let loaded = Settings::load_from(&path);
+        assert_eq!(
+            loaded.selected_model,
+            Some("claude-3-5-sonnet-20241022".to_string())
+        );
+    }
+
+    #[test]
+    fn test_model_or_default() {
+        let settings = Settings::default();
+        assert_eq!(
+            settings.model_or("default-model"),
+            "default-model".to_string()
+        );
+
+        let settings = Settings {
+            selected_model: Some("my-model".to_string()),
+        };
+        assert_eq!(settings.model_or("default-model"), "my-model".to_string());
+    }
+}