feat: persist filter state across sessions

llmfit-tui/src/filter_config.rs

@@ -0,0 +1,86 @@
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+use std::fs;
+use std::path::PathBuf;
+
+/// Persisted filter state, saved to `~/.config/llmfit/filters.json`.
+///
+/// Every field is optional so the file degrades gracefully when new filters are
+/// added or the model database changes between runs.  Multi-select filters are
+/// stored as `name -> selected` maps so additions/removals in the model list
+/// don't corrupt saved state.
+#[derive(Debug, Serialize, Deserialize, Default)]
+pub struct FilterConfig {
+    pub fit_filter: Option<String>,
+    pub availability_filter: Option<String>,
+    pub tp_filter: Option<String>,
+    pub sort_column: Option<String>,
+    pub sort_ascending: Option<bool>,
+    pub installed_first: Option<bool>,
+    pub search_query: Option<String>,
+
+    // Multi-select popup filters: name → selected
+    pub providers: Option<HashMap<String, bool>>,
+    pub use_cases: Option<HashMap<String, bool>>,
+    pub capabilities: Option<HashMap<String, bool>>,
+    pub quants: Option<HashMap<String, bool>>,
+    pub run_modes: Option<HashMap<String, bool>>,
+    pub params_buckets: Option<HashMap<String, bool>>,
+    pub licenses: Option<HashMap<String, bool>>,
+    pub runtimes: Option<HashMap<String, bool>>,
+}
+
+impl FilterConfig {
+    /// Path to the config file: `~/.config/llmfit/filters.json`
+    fn config_path() -> Option<PathBuf> {
+        let home = std::env::var("HOME")
+            .or_else(|_| std::env::var("USERPROFILE"))
+            .ok()?;
+        Some(
+            PathBuf::from(home)
+                .join(".config")
+                .join("llmfit")
+                .join("filters.json"),
+        )
+    }
+
+    /// Load the saved filter config from disk, falling back to defaults.
+    pub fn load() -> Self {
+        Self::config_path()
+            .and_then(|path| fs::read_to_string(path).ok())
+            .and_then(|s| serde_json::from_str(&s).ok())
+            .unwrap_or_default()
+    }
+
+    /// Save the current filter config to disk.
+    pub fn save(&self) {
+        if let Some(path) = Self::config_path() {
+            if let Some(parent) = path.parent() {
+                let _ = fs::create_dir_all(parent);
+            }
+            if let Ok(json) = serde_json::to_string_pretty(self) {
+                let _ = fs::write(&path, json);
+            }
+        }
+    }
+
+    /// Apply a saved name→selected map onto a positional `Vec<bool>`,
+    /// matching by the corresponding names vector.  Entries not present
+    /// in the saved map keep their current (default) value.
+    pub fn apply_map(names: &[String], selected: &mut [bool], saved: &HashMap<String, bool>) {
+        for (i, name) in names.iter().enumerate() {
+            if let Some(&val) = saved.get(name) {
+                selected[i] = val;
+            }
+        }
+    }
+
+    /// Build a name→selected map from parallel name and selected slices.
+    pub fn build_map(names: &[String], selected: &[bool]) -> HashMap<String, bool> {
+        names
+            .iter()
+            .zip(selected.iter())
+            .map(|(name, &sel)| (name.clone(), sel))
+            .collect()
+    }
+}

llmfit-tui/src/main.rs

@@ -1,4 +1,5 @@
 mod display;
+mod filter_config;
 mod serve_api;
 mod theme;
 mod tui_app;