refactor: extract platform-generic logic from run_ollama_model() handler

pdl-live-react/src-tauri/src/pdl/interpreter.rs

@@ -813,7 +813,8 @@ impl<'a> Interpreter<'a> {
         block: &ModelBlock,
         metadata: &Metadata,
         state: &mut State,
-    ) -> BodyInterpretation {
+        input_messages: Vec<ChatMessage>,
+    ) -> Result<(String, Option<PdlUsage>), PdlError> {
         let mut ollama = Ollama::default();
         let model = if pdl_model.starts_with("ollama/") {
             &pdl_model[7..]
@@ -827,19 +828,6 @@ impl<'a> Interpreter<'a> {
             eprintln!("Model tools {:?} {:?}", metadata.description, tools);
         }
 
-        let mut trace = block.clone();
-
-        // The input messages to the model is either:
-        // a) block.input, if given
-        // b) the current state's accumulated messages
-        let input_messages = match &block.input {
-            Some(input) => {
-                // TODO ignoring result and trace
-                let (_result, messages, _trace) = self.run_quiet(&*input, state).await?;
-                messages
-            }
-            None => state.messages.clone(),
-        };
         let (prompt, history_slice): (&ChatMessage, &[ChatMessage]) =
             match input_messages.split_last() {
                 Some(x) => x,
@@ -853,10 +841,6 @@ impl<'a> Interpreter<'a> {
             );
         }
 
-        //if state.emit {
-        //println!("{}", pretty_print(&input_messages));
-        //}
-
         let req = ChatMessageRequest::new(model.into(), vec![prompt.clone()])
             .options(options)
             .tools(tools);
@@ -919,6 +903,45 @@ impl<'a> Interpreter<'a> {
             }
         }
 
+        let usage = if let Some(res) = last_res {
+            if let Some(usage) = res.final_data {
+                Some(PdlUsage {
+                    prompt_tokens: usage.prompt_eval_count,
+                    prompt_nanos: Some(usage.prompt_eval_duration),
+                    completion_tokens: usage.eval_count,
+                    completion_nanos: Some(usage.eval_duration),
+                })
+            } else {
+                None
+            }
+        } else {
+            None
+        };
+
+        Ok((response_string, usage))
+    }
+
+    /// Run a PdlBlock::Model
+    async fn run_model(
+        &mut self,
+        block: &ModelBlock,
+        metadata: &Metadata,
+        state: &mut State,
+    ) -> BodyInterpretation {
+        // The input messages to the model is either:
+        // a) block.input, if given
+        // b) the current state's accumulated messages
+        let input_messages = match &block.input {
+            Some(input) => {
+                // TODO ignoring result and trace
+                let (_result, messages, _trace) = self.run_quiet(&*input, state).await?;
+                messages
+            }
+            None => state.messages.clone(),
+        };
+
+        let mut trace = block.clone();
+
         // TODO, does this belong in run_advanced(), and does
         // trace.context belong in Metadata rather than ModelBlock
         trace.context = Some(
@@ -948,42 +971,30 @@ impl<'a> Interpreter<'a> {
                 .collect(),
         );
 
-        if let Some(res) = last_res {
-            if let Some(usage) = res.final_data {
-                trace.pdl_usage = Some(PdlUsage {
-                    prompt_tokens: usage.prompt_eval_count,
-                    prompt_nanos: Some(usage.prompt_eval_duration),
-                    completion_tokens: usage.eval_count,
-                    completion_nanos: Some(usage.eval_duration),
-                });
-            }
-            let output_messages = vec![ChatMessage::assistant(response_string.clone())];
-            Ok((
-                PdlResult::String(response_string),
-                output_messages,
-                Model(trace),
-            ))
-        } else {
-            // nothing came out of the model
-            Ok(("".into(), vec![], Model(trace)))
-        }
-        // dbg!(history);
-    }
+        let (response_string, usage) =
+            if let PdlResult::String(s) = self.eval_string_to_string(&block.model, state)? {
+                if s.starts_with("ollama/") || s.starts_with("ollama_chat/") {
+                    self.run_ollama_model(s, block, metadata, state, input_messages)
+                        .await
+                /*} else if s.starts_with("openai/") {
+                return self.run_openai_model(s, block, metadata, state, input_messages).await;*/
+                } else {
+                    Err(Box::from(format!("Unsupported model {:?}", block.model)))
+                }
+            } else {
+                Err(Box::from(format!(
+                    "Model expression evaluated to non-string {:?}",
+                    block.model
+                )))
+            }?;
 
-    /// Run a PdlBlock::Model
-    async fn run_model(
-        &mut self,
-        block: &ModelBlock,
-        metadata: &Metadata,
-        state: &mut State,
-    ) -> BodyInterpretation {
-        if let PdlResult::String(s) = self.eval_string_to_string(&block.model, state)? {
-            if s.starts_with("ollama/") || s.starts_with("ollama_chat/") {
-                return self.run_ollama_model(s, block, metadata, state).await;
-            }
-        }
+        trace.pdl_usage = usage;
 
-        Err(Box::from(format!("Unsupported model {:?}", block.model)))
+        Ok((
+            PdlResult::String(response_string.clone()),
+            vec![ChatMessage::assistant(response_string)],
+            Model(trace),
+        ))
     }
 
     /// Run a PdlBlock::Data