import pickle
import os

FILE_PATH = "chat_history.pkl"

if not os.path.exists(FILE_PATH):
    with open(FILE_PATH, "wb") as file:
        pickle.dump({}, file)

def save_chat_entry(session_id, role, transcript):
    try:
        with open(FILE_PATH, "rb") as file:
            data = pickle.load(file)

        if session_id not in data:
            data[session_id] = []

        if role == "user":
            data[session_id].append({
                "role": role,
                "transcript": transcript
            })
        else:
            if data[session_id] and data[session_id][-1]['role'] == "assistant":
                data[session_id][-1]['transcript'] += " " + transcript
            else:
                data[session_id].append({
                    "role": role,
                    "transcript": transcript
                })

        with open(FILE_PATH, "wb") as file:
            pickle.dump(data, file)

    except Exception as e:
        print(f"Error saving chat entry: {e}")


def get_chat_history(session_id):
    try:
        with open(FILE_PATH, "rb") as file:
            data = pickle.load(file)

        chat_history = data.get(session_id, [])

        if not chat_history:
            return []

        message_history = []
        for entry in chat_history:
            role = entry.get('role', '')
            transcript = entry.get('transcript', '') 
            if role and transcript:
                message_history.append({"role": role, "content": transcript})

        return message_history

    except (FileNotFoundError, pickle.UnpicklingError) as e:
        print(f"Error reading or parsing the file: {e}")
        return [] 
    except Exception as e:
        print(f"Unexpected error: {e}")
        return []