fix: more accurate cost tracking hopefully

src-tauri/src/wsl_bridge.rs

@@ -717,16 +717,32 @@ fn process_json_line(
 
             // Only update stats if we have usage information
             if let Some(usage) = &message.usage {
-                if let Some(model) = &message.model {
+                // Get model from message, or fall back to last known model from stats
+                let model = message.model.clone().or_else(|| {
+                    let stats_guard = stats.read();
+                    stats_guard.model.clone()
+                }).unwrap_or_else(|| {
+                    println!("[WARNING] No model info available for cost calculation, using default");
+                    "claude-sonnet-4-5-20250929".to_string()
+                });
+
                 // Calculate cost for historical tracking (including cache tokens)
                 let cost_usd = calculate_cost(
                     usage.input_tokens,
                     usage.output_tokens,
-                        model,
+                    &model,
                     usage.cache_creation_input_tokens,
                     usage.cache_read_input_tokens,
                 );
 
+                println!("Assistant message tokens - input: {}, output: {}, cache_creation: {:?}, cache_read: {:?}, cost: ${:.4}",
+                    usage.input_tokens,
+                    usage.output_tokens,
+                    usage.cache_creation_input_tokens,
+                    usage.cache_read_input_tokens,
+                    cost_usd
+                );
+
                 // Store cost for later use in output events
                 message_cost = Some(MessageCost {
                     input_tokens: usage.input_tokens,
@@ -741,7 +757,7 @@ fn process_json_line(
                     stats_guard.add_usage(
                         usage.input_tokens,
                         usage.output_tokens,
-                            model,
+                        &model,
                         usage.cache_creation_input_tokens,
                         usage.cache_read_input_tokens,
                     );
@@ -771,10 +787,6 @@ fn process_json_line(
                 // Just increment message count if no usage info
                 stats.write().increment_messages();
             }
-            } else {
-                // Just increment message count if no usage info
-                stats.write().increment_messages();
-            }
 
             for block in &message.content {
                 match block {