Add chat functionality

src/heretic/main.py

@@ -222,14 +222,58 @@ def main():
     )
     print(f"  * Score: [bold]{-study.best_value:.4f}[/]")
 
-    return
-
     print()
-    action = questionary.select(
+    print("Restoring best model...")
-        "What do you want to do with the optimized model?",
+    print("* Reloading model...")
-        choices=[
+    model.reload_model()
-            "Save to a local folder",
+    print("* Abliterating...")
-            "Upload to Hugging Face",
+    model.abliterate(
-            "Nothing (discard the model)",
+        refusal_directions,
-        ],
+        study.best_params["max_weight"],
-    ).ask()
+        study.best_params["max_weight_position"],
+        study.best_params["min_weight"],
+        study.best_params["min_weight_distance"],
+    )
+
+    while True:
+        print()
+        action = questionary.select(
+            "What do you want to do with the optimized model?",
+            choices=[
+                "Save the model to a local folder",
+                "Upload the model to Hugging Face",
+                "Chat with the model",
+                "Nothing (Quit)",
+            ],
+        ).ask()
+
+        match action:
+            case "Save the model to a local folder":
+                # TODO
+                pass
+            case "Upload the model to Hugging Face":
+                # TODO
+                pass
+            case "Chat with the model":
+                print()
+                print("[cyan]Press Ctrl+C at any time to return to the menu.[/]")
+
+                chat = [
+                    {"role": "system", "content": settings.system_prompt},
+                ]
+
+                while True:
+                    try:
+                        message = questionary.text("User:", qmark=">").unsafe_ask()
+                        if not message:
+                            break
+                        chat.append({"role": "user", "content": message})
+
+                        print("[bold]Assistant:[/] ", end="")
+                        response = model.stream_chat_response(chat)
+                        chat.append({"role": "assistant", "content": response})
+                    except (KeyboardInterrupt, EOFError):
+                        # Ctrl+C/Ctrl+D
+                        break
+            case "Nothing (Quit)":
+                break

src/heretic/model.py

@@ -12,6 +12,7 @@ from transformers import (
     AutoTokenizer,
     BatchEncoding,
     PreTrainedTokenizerBase,
+    TextStreamer,
 )
 from transformers.generation.utils import GenerateOutput
 
@@ -251,3 +252,31 @@ class Model:
             logprobs.append(self.get_logprobs(batch))
 
         return torch.cat(logprobs, dim=0)
+
+    def stream_chat_response(self, chat: list[dict[str, str]]) -> str:
+        chat_prompt: str = self.tokenizer.apply_chat_template(
+            chat,
+            add_generation_prompt=True,
+            tokenize=False,
+        )
+
+        inputs = self.tokenizer(
+            chat_prompt,
+            return_tensors="pt",
+        ).to(self.model.device)
+
+        streamer = TextStreamer(
+            self.tokenizer,
+            skip_prompt=True,
+            skip_special_tokens=True,
+        )
+
+        outputs = self.model.generate(
+            **inputs,
+            streamer=streamer,
+        )
+
+        return self.tokenizer.decode(
+            outputs[0, inputs["input_ids"].shape[1] :],
+            skip_special_tokens=True,
+        )