refactor: Update filter API to use Read/Write traits

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

src/services/filter_service.rs

@@ -1,5 +1,5 @@
 use crate::filter_plugin::{FilterChain, parse_filter_string};
-use std::io::Result;
+use std::io::{Result, Read, Write};
 
 pub struct FilterService;
 
@@ -16,44 +16,33 @@ impl FilterService {
         }
     }
 
-    pub fn process_data(&self, chain: &mut Option<FilterChain>, data: &[u8]) -> Result<Vec<u8>> {
+    pub fn filter_data<R: Read, W: Write>(
+        &self, 
+        chain: &mut Option<FilterChain>, 
+        reader: &mut R, 
+        writer: &mut W
+    ) -> Result<()> {
         if let Some(chain) = chain {
-            chain.process(data)
+            chain.filter(reader, writer)
         } else {
-            Ok(data.to_vec())
+            // If no filter chain, just copy the input to output
+            std::io::copy(reader, writer)?;
+            Ok(())
         }
     }
 
-    pub fn finish_processing(&self, chain: &mut Option<FilterChain>) -> Result<Vec<u8>> {
-        if let Some(chain) = chain {
-            chain.finish()
-        } else {
-            Ok(Vec::new())
-        }
-    }
-
-    // Add a method to process data through the filter chain and handle finish automatically
-    pub fn process_all_data(&self, chain: &mut Option<FilterChain>, data: &[u8]) -> Result<Vec<u8>> {
-        let mut processed = if let Some(chain) = chain {
-            chain.process(data)?
-        } else {
-            data.to_vec()
-        };
-        
-        // If we have a chain, also get any remaining data from finish()
-        if chain.is_some() {
-            let finished = self.finish_processing(chain)?;
-            if !finished.is_empty() {
-                processed.extend(finished);
-            }
-        }
-        
-        Ok(processed)
-    }
-
-    // Helper method to create and process data with a filter string in one call
+    // Helper method to process data with a filter string in one call
     pub fn process_with_filter(&self, data: &[u8], filter_str: Option<&str>) -> Result<Vec<u8>> {
         let mut chain = self.create_filter_chain(filter_str)?;
-        self.process_all_data(&mut chain, data)
+        let mut reader = std::io::Cursor::new(data);
+        let mut writer = Vec::new();
+        
+        if let Some(ref mut chain) = chain {
+            chain.filter(&mut reader, &mut writer)?;
+        } else {
+            std::io::copy(&mut reader, &mut writer)?;
+        }
+        
+        Ok(writer)
     }
 }