refactor: Use plugin registry for filter service discovery

Co-authored-by: aider (openai/andrew/openrouter/deepseek/deepseek-chat-v3.1) <aider@aider.chat>

Cargo.toml

@@ -19,6 +19,7 @@ base64 = "0.22.1"
 chrono = "0.4.26"
 clap = { version = "4.3.10", features = ["derive", "env"] }
 config = "0.14.0"
+ctor = "0.2"
 directories = "6.0.0"
 dns-lookup = "2.0.2"
 enum-map = "2.6.1"

src/filter_plugin/head.rs

@@ -1,6 +1,7 @@
 use super::{FilterPlugin, FilterOption};
 use std::io::{Result, Read, Write, BufRead};
 use crate::common::PIPESIZE;
+use crate::services::filter_service::register_filter_plugin;
 
 pub struct HeadBytesFilter {
     remaining: usize,
@@ -96,3 +97,10 @@ impl FilterPlugin for HeadLinesFilter {
         ]
     }
 }
+
+// Register the plugin at module initialization time
+#[ctor::ctor]
+fn register_head_filters() {
+    register_filter_plugin("head_bytes", || Box::new(HeadBytesFilter::new(0)));
+    register_filter_plugin("head_lines", || Box::new(HeadLinesFilter::new(0)));
+}

src/services/filter_service.rs

@@ -1,6 +1,8 @@
 use crate::filter_plugin::{FilterChain, parse_filter_string};
 use std::collections::HashMap;
 use std::io::{Result, Read, Write};
+use once_cell::sync::Lazy;
+use std::sync::Mutex;
 
 pub struct FilterService;
 
@@ -48,52 +50,16 @@ impl FilterService {
     }
 }
 
+/// Global registry for filter plugins
+static FILTER_PLUGIN_REGISTRY: Lazy<Mutex<HashMap<String, fn() -> Box<dyn crate::filter_plugin::FilterPlugin>>>> = 
+    Lazy::new(|| Mutex::new(HashMap::new()));
+
+/// Register a filter plugin with the global registry
+pub fn register_filter_plugin(name: &str, constructor: fn() -> Box<dyn crate::filter_plugin::FilterPlugin>) {
+    FILTER_PLUGIN_REGISTRY.lock().unwrap().insert(name.to_string(), constructor);
+}
+
 /// Get a map of available filter plugins
 pub fn get_available_filter_plugins() -> HashMap<String, fn() -> Box<dyn crate::filter_plugin::FilterPlugin>> {
-    let mut plugins = HashMap::new();
+    FILTER_PLUGIN_REGISTRY.lock().unwrap().clone()
-    
-    // Register all available filter plugins using function pointers
-    plugins.insert("head_bytes".to_string(), create_head_bytes_filter);
-    plugins.insert("head_lines".to_string(), create_head_lines_filter);
-    plugins.insert("tail_bytes".to_string(), create_tail_bytes_filter);
-    plugins.insert("tail_lines".to_string(), create_tail_lines_filter);
-    plugins.insert("skip_bytes".to_string(), create_skip_bytes_filter);
-    plugins.insert("skip_lines".to_string(), create_skip_lines_filter);
-    plugins.insert("grep".to_string(), create_grep_filter);
-    plugins.insert("strip_ansi".to_string(), create_strip_ansi_filter);
-    
-    plugins
-}
-
-// Helper functions to create each filter plugin
-fn create_head_bytes_filter() -> Box<dyn crate::filter_plugin::FilterPlugin> {
-    Box::new(crate::filter_plugin::head::HeadBytesFilter::new(0))
-}
-
-fn create_head_lines_filter() -> Box<dyn crate::filter_plugin::FilterPlugin> {
-    Box::new(crate::filter_plugin::head::HeadLinesFilter::new(0))
-}
-
-fn create_tail_bytes_filter() -> Box<dyn crate::filter_plugin::FilterPlugin> {
-    Box::new(crate::filter_plugin::tail::TailBytesFilter::new(0))
-}
-
-fn create_tail_lines_filter() -> Box<dyn crate::filter_plugin::FilterPlugin> {
-    Box::new(crate::filter_plugin::tail::TailLinesFilter::new(0))
-}
-
-fn create_skip_bytes_filter() -> Box<dyn crate::filter_plugin::FilterPlugin> {
-    Box::new(crate::filter_plugin::skip::SkipBytesFilter::new(0))
-}
-
-fn create_skip_lines_filter() -> Box<dyn crate::filter_plugin::FilterPlugin> {
-    Box::new(crate::filter_plugin::skip::SkipLinesFilter::new(0))
-}
-
-fn create_grep_filter() -> Box<dyn crate::filter_plugin::FilterPlugin> {
-    Box::new(crate::filter_plugin::grep::GrepFilter::new("".to_string()).unwrap())
-}
-
-fn create_strip_ansi_filter() -> Box<dyn crate::filter_plugin::FilterPlugin> {
-    Box::new(crate::filter_plugin::strip_ansi::StripAnsiFilter::new())
 }