chatfuncs/chatfuncs.py

import re
import os
import datetime
from typing import Type, Dict, List, Tuple
import time
from itertools import compress
import pandas as pd
import numpy as np

# Model packages
import torch.cuda
from threading import Thread
from transformers import pipeline, TextIteratorStreamer

# Alternative model sources
#from dataclasses import asdict, dataclass

# Langchain functions
from langchain.prompts import PromptTemplate
from langchain_community.vectorstores import FAISS
from langchain_community.retrievers import SVMRetriever 
from langchain.text_splitter import RecursiveCharacterTextSplitter
from langchain.docstore.document import Document

# For keyword extraction (not currently used)
#import nltk
#nltk.download('wordnet')
from nltk.corpus import stopwords
from nltk.tokenize import RegexpTokenizer
from nltk.stem import WordNetLemmatizer
from keybert import KeyBERT

# For Name Entity Recognition model
#from span_marker import SpanMarkerModel # Not currently used

# For BM25 retrieval
from gensim.corpora import Dictionary
from gensim.models import TfidfModel, OkapiBM25Model
from gensim.similarities import SparseMatrixSimilarity

from llama_cpp import Llama
from huggingface_hub import hf_hub_download

from chatfuncs.prompts import instruction_prompt_template_alpaca, instruction_prompt_mistral_orca, instruction_prompt_phi3, instruction_prompt_llama3

import gradio as gr

torch.cuda.empty_cache()

PandasDataFrame = Type[pd.DataFrame]

embeddings = None  # global variable setup
vectorstore = None # global variable setup
model_type = None # global variable setup

max_memory_length = 0 # How long should the memory of the conversation last?

full_text = "" # Define dummy source text (full text) just to enable highlight function to load

model = [] # Define empty list for model functions to run
tokenizer = [] # Define empty list for model functions to run

## Highlight text constants
hlt_chunk_size = 12
hlt_strat = [" ", ". ", "! ", "? ", ": ", "\n\n", "\n", ", "]
hlt_overlap = 4

## Initialise NER model ##
ner_model = []#SpanMarkerModel.from_pretrained("tomaarsen/span-marker-mbert-base-multinerd") # Not currently used

## Initialise keyword model ##
# Used to pull out keywords from chat history to add to user queries behind the scenes
kw_model = pipeline("feature-extraction", model="sentence-transformers/all-MiniLM-L6-v2")

# Currently set gpu_layers to 0 even with cuda due to persistent bugs in implementation with cuda
if torch.cuda.is_available():
    torch_device = "cuda"
    gpu_layers = 100
else: 
    torch_device =  "cpu"
    gpu_layers = 0

print("Running on device:", torch_device)
threads = 8 #torch.get_num_threads()
print("CPU threads:", threads)

# Flan Alpaca (small, fast) Model parameters
temperature: float = 0.1
top_k: int = 3
top_p: float = 1
repetition_penalty: float = 1.15
flan_alpaca_repetition_penalty: float = 1.3
last_n_tokens: int = 64
max_new_tokens: int = 1024
seed: int = 42
reset: bool = False
stream: bool = True
threads: int = threads
batch_size:int = 256
context_length:int = 2048
sample = True


class CtransInitConfig_gpu:
    def __init__(self,
                 last_n_tokens=last_n_tokens,
                 seed=seed,
                 n_threads=threads,
                 n_batch=batch_size,
                 n_ctx=4096,
                 n_gpu_layers=gpu_layers):

        self.last_n_tokens = last_n_tokens
        self.seed = seed
        self.n_threads = n_threads
        self.n_batch = n_batch
        self.n_ctx = n_ctx
        self.n_gpu_layers = n_gpu_layers
        # self.stop: list[str] = field(default_factory=lambda: [stop_string])

    def update_gpu(self, new_value):
        self.n_gpu_layers = new_value

class CtransInitConfig_cpu(CtransInitConfig_gpu):
    def __init__(self):
        super().__init__()
        self.n_gpu_layers = 0

gpu_config = CtransInitConfig_gpu()
cpu_config = CtransInitConfig_cpu()


class CtransGenGenerationConfig:
    def __init__(self, temperature=temperature,
                 top_k=top_k,
                 top_p=top_p,
                 repeat_penalty=repetition_penalty,
                 seed=seed,
                 stream=stream,
                 max_tokens=max_new_tokens
                 ):
        self.temperature = temperature
        self.top_k = top_k
        self.top_p = top_p
        self.repeat_penalty = repeat_penalty
        self.seed = seed
        self.max_tokens=max_tokens
        self.stream = stream

    def update_temp(self, new_value):
        self.temperature = new_value

# Vectorstore funcs

def docs_to_faiss_save(docs_out:PandasDataFrame, embeddings=embeddings):

    print(f"> Total split documents: {len(docs_out)}")

    vectorstore_func = FAISS.from_documents(documents=docs_out, embedding=embeddings)
        
    '''  
    #with open("vectorstore.pkl", "wb") as f:
        #pickle.dump(vectorstore, f) 
    ''' 

    #if Path(save_to).exists():
    #    vectorstore_func.save_local(folder_path=save_to)
    #else:
    #    os.mkdir(save_to)
    #    vectorstore_func.save_local(folder_path=save_to)

    global vectorstore

    vectorstore = vectorstore_func

    out_message = "Document processing complete"

    #print(out_message)
    #print(f"> Saved to: {save_to}")

    return out_message

# Prompt functions

def base_prompt_templates(model_type = "Flan Alpaca (small, fast)"):    
  
    #EXAMPLE_PROMPT = PromptTemplate(
    #    template="\nCONTENT:\n\n{page_content}\n\nSOURCE: {source}\n\n",
    #    input_variables=["page_content", "source"],
    #)

    CONTENT_PROMPT = PromptTemplate(
        template="{page_content}\n\n",#\n\nSOURCE: {source}\n\n",
        input_variables=["page_content"]
    )

# The main prompt:  

    if model_type == "Flan Alpaca (small, fast)":
        INSTRUCTION_PROMPT=PromptTemplate(template=instruction_prompt_template_alpaca, input_variables=['question', 'summaries'])
    elif model_type == "Phi 3 Mini (larger, slow)":
        INSTRUCTION_PROMPT=PromptTemplate(template=instruction_prompt_phi3, input_variables=['question', 'summaries'])

    return INSTRUCTION_PROMPT, CONTENT_PROMPT

def write_out_metadata_as_string(metadata_in):
    metadata_string = [f"{'  '.join(f'{k}: {v}' for k, v in d.items() if k != 'page_section')}" for d in metadata_in] # ['metadata']
    return metadata_string

def generate_expanded_prompt(inputs: Dict[str, str], instruction_prompt, content_prompt, extracted_memory, vectorstore, embeddings, out_passages = 2): # , 
        
        question =  inputs["question"]
        chat_history = inputs["chat_history"]
        

        new_question_kworded = adapt_q_from_chat_history(question, chat_history, extracted_memory) # new_question_keywords, 
        
       
        docs_keep_as_doc, doc_df, docs_keep_out = hybrid_retrieval(new_question_kworded, vectorstore, embeddings, k_val = 25, out_passages = out_passages,
                                                                          vec_score_cut_off = 0.85, vec_weight = 1, bm25_weight = 1, svm_weight = 1)#,
                                                                          #vectorstore=globals()["vectorstore"], embeddings=globals()["embeddings"])
        
        #print(docs_keep_as_doc)
        #print(doc_df)
        if (not docs_keep_as_doc) | (doc_df.empty):
            sorry_prompt = """Say 'Sorry, there is no relevant information to answer this question.'.
RESPONSE:"""
            return sorry_prompt, "No relevant sources found.", new_question_kworded
        
        # Expand the found passages to the neighbouring context
        file_type = determine_file_type(doc_df['meta_url'][0])

        # Only expand passages if not tabular data
        if (file_type != ".csv") & (file_type != ".xlsx"):
            docs_keep_as_doc, doc_df = get_expanded_passages(vectorstore, docs_keep_out, width=3)

        
 
        # Build up sources content to add to user display
        doc_df['meta_clean'] = write_out_metadata_as_string(doc_df["metadata"]) # [f"<b>{'  '.join(f'{k}: {v}' for k, v in d.items() if k != 'page_section')}</b>" for d in doc_df['metadata']]
        
        # Remove meta text from the page content if it already exists there
        doc_df['page_content_no_meta'] = doc_df.apply(lambda row: row['page_content'].replace(row['meta_clean'] + ". ", ""), axis=1)
        doc_df['content_meta'] = doc_df['meta_clean'].astype(str) + ".<br><br>" + doc_df['page_content_no_meta'].astype(str)

        #modified_page_content = [f" Document {i+1} - {word}" for i, word in enumerate(doc_df['page_content'])]
        modified_page_content = [f" Document {i+1} - {word}" for i, word in enumerate(doc_df['content_meta'])]
        docs_content_string = '<br><br>'.join(modified_page_content)

        sources_docs_content_string = '<br><br>'.join(doc_df['content_meta'])#.replace("  "," ")#.strip()
     
        instruction_prompt_out = instruction_prompt.format(question=new_question_kworded, summaries=docs_content_string)
        
        print('Final prompt is: ')
        print(instruction_prompt_out)
                
        return instruction_prompt_out, sources_docs_content_string, new_question_kworded

def create_full_prompt(user_input, history, extracted_memory, vectorstore, embeddings, model_type, out_passages):
    
    if not user_input.strip():
        return history, "", "Respond with 'Please enter a question.' RESPONSE:"

    #if chain_agent is None:
    #    history.append((user_input, "Please click the button to submit the Huggingface API key before using the chatbot (top right)"))
    #    return history, history, "", ""
    print("\n==== date/time: " + str(datetime.datetime.now()) + " ====")
    print("User input: " + user_input)
    
    history = history or []
    
    # Create instruction prompt
    instruction_prompt, content_prompt = base_prompt_templates(model_type=model_type)
    instruction_prompt_out, docs_content_string, new_question_kworded =\
                generate_expanded_prompt({"question": user_input, "chat_history": history}, #vectorstore,
                                    instruction_prompt, content_prompt, extracted_memory, vectorstore, embeddings, out_passages)
    
  
    history.append(user_input)
    
    print("Output history is:")
    print(history)

    print("Final prompt to model is:")
    print(instruction_prompt_out)
        
    return history, docs_content_string, instruction_prompt_out

# Chat functions

def produce_streaming_answer_chatbot(history, full_prompt, model_type,
            temperature=temperature,
            max_new_tokens=max_new_tokens,
            sample=sample,
            repetition_penalty=repetition_penalty,
            top_p=top_p,
            top_k=top_k
):
    #print("Model type is: ", model_type)

    #if not full_prompt.strip():
    #    if history is None:
    #        history = []

    #    return history

    if model_type == "Flan Alpaca (small, fast)": 
        # Get the model and tokenizer, and tokenize the user text.
        model_inputs = tokenizer(text=full_prompt, return_tensors="pt", return_attention_mask=False).to(torch_device)
        
        # Start generation on a separate thread, so that we don't block the UI. The text is pulled from the streamer
        # in the main thread. Adds timeout to the streamer to handle exceptions in the generation thread.
        streamer = TextIteratorStreamer(tokenizer, timeout=120., skip_prompt=True, skip_special_tokens=True)
        generate_kwargs = dict(
            model_inputs,
            streamer=streamer,
            max_new_tokens=max_new_tokens,
            do_sample=sample,
            repetition_penalty=repetition_penalty,
            top_p=top_p,
            temperature=temperature,
            top_k=top_k
        )

        print(generate_kwargs)

        t = Thread(target=model.generate, kwargs=generate_kwargs)
        t.start()

        # Pull the generated text from the streamer, and update the model output.
        start = time.time()
        NUM_TOKENS=0
        print('-'*4+'Start Generation'+'-'*4)

        history[-1][1] = ""
        for new_text in streamer:
            try:
                if new_text == None: new_text = ""
                history[-1][1] += new_text
                NUM_TOKENS+=1
                yield history
            except Exception as e:
                print(f"Error during text generation: {e}")
            
        time_generate = time.time() - start
        print('\n')
        print('-'*4+'End Generation'+'-'*4)
        print(f'Num of generated tokens: {NUM_TOKENS}')
        print(f'Time for complete generation: {time_generate}s')
        print(f'Tokens per secound: {NUM_TOKENS/time_generate}')
        print(f'Time per token: {(time_generate/NUM_TOKENS)*1000}ms')

    elif model_type == "Phi 3 Mini (larger, slow)":
        #tokens = model.tokenize(full_prompt)

        gen_config = CtransGenGenerationConfig()
        gen_config.update_temp(temperature)

        print(vars(gen_config))

        # Pull the generated text from the streamer, and update the model output.
        start = time.time()
        NUM_TOKENS=0
        print('-'*4+'Start Generation'+'-'*4)

        output = model(
        full_prompt, **vars(gen_config))

        history[-1][1] = ""
        for out in output:

            if "choices" in out and len(out["choices"]) > 0 and "text" in out["choices"][0]:
                history[-1][1] += out["choices"][0]["text"]
                NUM_TOKENS+=1
                yield history
            else:
                print(f"Unexpected output structure: {out}") 

        time_generate = time.time() - start
        print('\n')
        print('-'*4+'End Generation'+'-'*4)
        print(f'Num of generated tokens: {NUM_TOKENS}')
        print(f'Time for complete generation: {time_generate}s')
        print(f'Tokens per secound: {NUM_TOKENS/time_generate}')
        print(f'Time per token: {(time_generate/NUM_TOKENS)*1000}ms')


# Chat helper functions

def adapt_q_from_chat_history(question, chat_history, extracted_memory, keyword_model=""):#keyword_model): # new_question_keywords, 
 
        chat_history_str, chat_history_first_q, chat_history_first_ans, max_memory_length = _get_chat_history(chat_history)

        if chat_history_str:
            # Keyword extraction is now done in the add_inputs_to_history function
            #remove_q_stopwords(str(chat_history_first_q) + " " + str(chat_history_first_ans))
            
           
            new_question_kworded = str(extracted_memory) + ". " + question #+ " " + new_question_keywords
            #extracted_memory + " " + question
            
        else:
            new_question_kworded = question #new_question_keywords

        #print("Question output is: " + new_question_kworded)
            
        return new_question_kworded

def determine_file_type(file_path):
        """
        Determine the file type based on its extension.
    
        Parameters:
            file_path (str): Path to the file.
    
        Returns:
            str: File extension (e.g., '.pdf', '.docx', '.txt', '.html').
        """
        return os.path.splitext(file_path)[1].lower()


def create_doc_df(docs_keep_out):
    # Extract content and metadata from 'winning' passages.
            content=[]
            meta=[]
            meta_url=[]
            page_section=[]
            score=[]

            doc_df = pd.DataFrame()

            

            for item in docs_keep_out:
                content.append(item[0].page_content)
                meta.append(item[0].metadata)
                meta_url.append(item[0].metadata['source'])

                file_extension = determine_file_type(item[0].metadata['source'])
                if (file_extension != ".csv") & (file_extension != ".xlsx"):
                    page_section.append(item[0].metadata['page_section'])
                else: page_section.append("")
                score.append(item[1])       

            # Create df from 'winning' passages

            doc_df = pd.DataFrame(list(zip(content, meta, page_section, meta_url, score)),
               columns =['page_content', 'metadata', 'page_section', 'meta_url', 'score'])

            docs_content = doc_df['page_content'].astype(str)
            doc_df['full_url'] = "https://" + doc_df['meta_url'] 

            return doc_df

def hybrid_retrieval(new_question_kworded, vectorstore, embeddings, k_val, out_passages,
                           vec_score_cut_off, vec_weight, bm25_weight, svm_weight): # ,vectorstore, embeddings

            #vectorstore=globals()["vectorstore"]
            #embeddings=globals()["embeddings"]
            doc_df = pd.DataFrame()


            docs = vectorstore.similarity_search_with_score(new_question_kworded, k=k_val)

            print("Docs from similarity search:")
            print(docs)

            # Keep only documents with a certain score
            docs_len = [len(x[0].page_content) for x in docs]
            docs_scores = [x[1] for x in docs]

            # Only keep sources that are sufficiently relevant (i.e. similarity search score below threshold below)
            score_more_limit = pd.Series(docs_scores) < vec_score_cut_off
            docs_keep = list(compress(docs, score_more_limit))

            if not docs_keep:
                return [], pd.DataFrame(), []

            # Only keep sources that are at least 100 characters long
            length_more_limit = pd.Series(docs_len) >= 100
            docs_keep = list(compress(docs_keep, length_more_limit))

            if not docs_keep:
                return [], pd.DataFrame(), []

            docs_keep_as_doc = [x[0] for x in docs_keep]
            docs_keep_length = len(docs_keep_as_doc)


                
            if docs_keep_length == 1:

                content=[]
                meta_url=[]
                score=[]
                
                for item in docs_keep:
                    content.append(item[0].page_content)
                    meta_url.append(item[0].metadata['source'])
                    score.append(item[1])       

                # Create df from 'winning' passages

                doc_df = pd.DataFrame(list(zip(content, meta_url, score)),
                columns =['page_content', 'meta_url', 'score'])

                docs_content = doc_df['page_content'].astype(str)
                docs_url = doc_df['meta_url']

                return docs_keep_as_doc, docs_content, docs_url
            
            # Check for if more docs are removed than the desired output
            if out_passages > docs_keep_length: 
                out_passages = docs_keep_length
                k_val = docs_keep_length
                     
            vec_rank = [*range(1, docs_keep_length+1)]
            vec_score = [(docs_keep_length/x)*vec_weight for x in vec_rank]

            print("Number of documents remaining: ", docs_keep_length)
            
            # 2nd level check on retrieved docs with BM25

            content_keep=[]
            for item in docs_keep:
                content_keep.append(item[0].page_content)

            corpus = corpus = [doc.lower().split() for doc in content_keep]
            dictionary = Dictionary(corpus)
            bm25_model = OkapiBM25Model(dictionary=dictionary)
            bm25_corpus = bm25_model[list(map(dictionary.doc2bow, corpus))]
            bm25_index = SparseMatrixSimilarity(bm25_corpus, num_docs=len(corpus), num_terms=len(dictionary),
                                   normalize_queries=False, normalize_documents=False)
            query = new_question_kworded.lower().split()
            tfidf_model = TfidfModel(dictionary=dictionary, smartirs='bnn')  # Enforce binary weighting of queries
            tfidf_query = tfidf_model[dictionary.doc2bow(query)]
            similarities = np.array(bm25_index[tfidf_query])
            #print(similarities)
            temp = similarities.argsort()
            ranks = np.arange(len(similarities))[temp.argsort()][::-1]

            # Pair each index with its corresponding value
            pairs = list(zip(ranks, docs_keep_as_doc))
            # Sort the pairs by the indices
            pairs.sort()
            # Extract the values in the new order
            bm25_result = [value for ranks, value in pairs]
            
            bm25_rank=[]
            bm25_score = []

            for vec_item in docs_keep:
                x = 0
                for bm25_item in bm25_result:
                    x = x + 1
                    if bm25_item.page_content == vec_item[0].page_content:
                        bm25_rank.append(x)
                        bm25_score.append((docs_keep_length/x)*bm25_weight)

            # 3rd level check on retrieved docs with SVM retriever

            svm_retriever = SVMRetriever.from_texts(content_keep, embeddings, k = k_val)
            svm_result = svm_retriever.invoke(new_question_kworded)

         
            svm_rank=[]
            svm_score = []

            for vec_item in docs_keep:
                x = 0
                for svm_item in svm_result:
                    x = x + 1
                    if svm_item.page_content == vec_item[0].page_content:
                        svm_rank.append(x)
                        svm_score.append((docs_keep_length/x)*svm_weight)

        
            ## Calculate final score based on three ranking methods
            final_score = [a  + b + c for a, b, c in zip(vec_score, bm25_score, svm_score)]
            final_rank = [sorted(final_score, reverse=True).index(x)+1 for x in final_score]
            # Force final_rank to increment by 1 each time
            final_rank = list(pd.Series(final_rank).rank(method='first'))

            #print("final rank: " + str(final_rank))
            #print("out_passages: " + str(out_passages))

            best_rank_index_pos = []

            for x in range(1,out_passages+1):
                try:
                    best_rank_index_pos.append(final_rank.index(x))
                except IndexError: # catch the error
                    pass

            # Adjust best_rank_index_pos to 

            best_rank_pos_series = pd.Series(best_rank_index_pos)


            docs_keep_out = [docs_keep[i] for i in best_rank_index_pos]
        
            # Keep only 'best' options
            docs_keep_as_doc = [x[0] for x in docs_keep_out]
                               
            # Make df of best options
            doc_df = create_doc_df(docs_keep_out)

            return docs_keep_as_doc, doc_df, docs_keep_out

def get_expanded_passages(vectorstore, docs, width):

    """
    Extracts expanded passages based on given documents and a width for context.
    
    Parameters:
    - vectorstore: The primary data source.
    - docs: List of documents to be expanded.
    - width: Number of documents to expand around a given document for context.
    
    Returns:
    - expanded_docs: List of expanded Document objects.
    - doc_df: DataFrame representation of expanded_docs.
    """

    from collections import defaultdict
    
    def get_docs_from_vstore(vectorstore):
        vector = vectorstore.docstore._dict
        return list(vector.items())

    def extract_details(docs_list):
        docs_list_out = [tup[1] for tup in docs_list]
        content = [doc.page_content for doc in docs_list_out]
        meta = [doc.metadata for doc in docs_list_out]
        return ''.join(content), meta[0], meta[-1]
    
    def get_parent_content_and_meta(vstore_docs, width, target):
        #target_range = range(max(0, target - width), min(len(vstore_docs), target + width + 1))
        target_range = range(max(0, target), min(len(vstore_docs), target + width + 1)) # Now only selects extra passages AFTER the found passage
        parent_vstore_out = [vstore_docs[i] for i in target_range]
        
        content_str_out, meta_first_out, meta_last_out = [], [], []
        for _ in parent_vstore_out:
            content_str, meta_first, meta_last = extract_details(parent_vstore_out)
            content_str_out.append(content_str)
            meta_first_out.append(meta_first)
            meta_last_out.append(meta_last)
        return content_str_out, meta_first_out, meta_last_out

    def merge_dicts_except_source(d1, d2):
            merged = {}
            for key in d1:
                if key != "source":
                    merged[key] = str(d1[key]) + " to " + str(d2[key])
                else:
                    merged[key] = d1[key]  # or d2[key], based on preference
            return merged

    def merge_two_lists_of_dicts(list1, list2):
        return [merge_dicts_except_source(d1, d2) for d1, d2 in zip(list1, list2)]

    # Step 1: Filter vstore_docs
    vstore_docs = get_docs_from_vstore(vectorstore)
    doc_sources = {doc.metadata['source'] for doc, _ in docs}
    vstore_docs = [(k, v) for k, v in vstore_docs if v.metadata.get('source') in doc_sources]

    # Step 2: Group by source and proceed
    vstore_by_source = defaultdict(list)
    for k, v in vstore_docs:
        vstore_by_source[v.metadata['source']].append((k, v))
        
    expanded_docs = []
    for doc, score in docs:
        search_source = doc.metadata['source']
        

        #if file_type == ".csv" | file_type == ".xlsx":
        #     content_str, meta_first, meta_last = get_parent_content_and_meta(vstore_by_source[search_source], 0, search_index)

        #else:
        search_section = doc.metadata['page_section']
        parent_vstore_meta_section = [doc.metadata['page_section'] for _, doc in vstore_by_source[search_source]]
        search_index = parent_vstore_meta_section.index(search_section) if search_section in parent_vstore_meta_section else -1

        content_str, meta_first, meta_last = get_parent_content_and_meta(vstore_by_source[search_source], width, search_index)
        meta_full = merge_two_lists_of_dicts(meta_first, meta_last)

        expanded_doc = (Document(page_content=content_str[0], metadata=meta_full[0]), score)
        expanded_docs.append(expanded_doc)

    doc_df = pd.DataFrame()

    doc_df = create_doc_df(expanded_docs)  # Assuming you've defined the 'create_doc_df' function elsewhere

    return expanded_docs, doc_df

def highlight_found_text(search_text: str, full_text: str, hlt_chunk_size:int=hlt_chunk_size, hlt_strat:List=hlt_strat, hlt_overlap:int=hlt_overlap) -> str:
    """
    Highlights occurrences of search_text within full_text.
    
    Parameters:
    - search_text (str): The text to be searched for within full_text.
    - full_text (str): The text within which search_text occurrences will be highlighted.
    
    Returns:
    - str: A string with occurrences of search_text highlighted.
    
    Example:
    >>> highlight_found_text("world", "Hello, world! This is a test. Another world awaits.")
    'Hello, <mark style="color:black;">world</mark>! This is a test. Another <mark style="color:black;">world</mark> awaits.'
    """

    def extract_text_from_input(text, i=0):
        if isinstance(text, str):
            return text.replace("  ", " ").strip()
        elif isinstance(text, list):
            return text[i][0].replace("  ", " ").strip()
        else:
            return ""

    def extract_search_text_from_input(text):
        if isinstance(text, str):
            return text.replace("  ", " ").strip()
        elif isinstance(text, list):
            return text[-1][1].replace("  ", " ").strip()
        else:
            return ""

    full_text = extract_text_from_input(full_text)
    search_text = extract_search_text_from_input(search_text)



    text_splitter = RecursiveCharacterTextSplitter(
        chunk_size=hlt_chunk_size,
        separators=hlt_strat,
        chunk_overlap=hlt_overlap,
    )
    sections = text_splitter.split_text(search_text)

    found_positions = {}
    for x in sections:
        text_start_pos = 0
        while text_start_pos != -1:
            text_start_pos = full_text.find(x, text_start_pos)
            if text_start_pos != -1:
                found_positions[text_start_pos] = text_start_pos + len(x)
                text_start_pos += 1

    # Combine overlapping or adjacent positions
    sorted_starts = sorted(found_positions.keys())
    combined_positions = []
    if sorted_starts:
        current_start, current_end = sorted_starts[0], found_positions[sorted_starts[0]]
        for start in sorted_starts[1:]:
            if start <= (current_end + 10):
                current_end = max(current_end, found_positions[start])
            else:
                combined_positions.append((current_start, current_end))
                current_start, current_end = start, found_positions[start]
        combined_positions.append((current_start, current_end))

    # Construct pos_tokens
    pos_tokens = []
    prev_end = 0
    for start, end in combined_positions:
        if end-start > 15: # Only combine if there is a significant amount of matched text. Avoids picking up single words like 'and' etc.
            pos_tokens.append(full_text[prev_end:start])
            pos_tokens.append('<mark style="color:black;">' + full_text[start:end] + '</mark>')
            prev_end = end
    pos_tokens.append(full_text[prev_end:])

    return "".join(pos_tokens)


# # Chat history functions

def clear_chat(chat_history_state, sources, chat_message, current_topic):
    chat_history_state = []
    sources = ''
    chat_message = ''
    current_topic = ''

    return chat_history_state, sources, chat_message, current_topic

def _get_chat_history(chat_history: List[Tuple[str, str]], max_memory_length:int = max_memory_length): # Limit to last x interactions only

    if (not chat_history) | (max_memory_length == 0):
        chat_history = []

    if len(chat_history) > max_memory_length:
        chat_history = chat_history[-max_memory_length:]
        
    #print(chat_history)

    first_q = ""
    first_ans = ""
    for human_s, ai_s in chat_history:
        first_q = human_s
        first_ans = ai_s

        #print("Text to keyword extract: " + first_q + " " + first_ans)
        break

    conversation = ""
    for human_s, ai_s in chat_history:
        human = f"Human: " + human_s
        ai = f"Assistant: " + ai_s
        conversation += "\n" + "\n".join([human, ai])

    return conversation, first_q, first_ans, max_memory_length

def add_inputs_answer_to_history(user_message, history, current_topic):
    
    if history is None:
        history = [("","")]

    #history.append((user_message, [-1]))

    chat_history_str, chat_history_first_q, chat_history_first_ans, max_memory_length = _get_chat_history(history)


    # Only get the keywords for the first question and response, or do it every time if over 'max_memory_length' responses in the conversation
    if (len(history) == 1) | (len(history) > max_memory_length):
        
        #print("History after appending is:")
        #print(history)

        first_q_and_first_ans = str(chat_history_first_q) + " " + str(chat_history_first_ans)
        #ner_memory = remove_q_ner_extractor(first_q_and_first_ans)
        keywords = keybert_keywords(first_q_and_first_ans, n = 8, kw_model=kw_model)
        #keywords.append(ner_memory)

        # Remove duplicate words while preserving order
        ordered_tokens = set()
        result = []
        for word in keywords:
                if word not in ordered_tokens:
                        ordered_tokens.add(word)
                        result.append(word)

        extracted_memory = ' '.join(result)

    else: extracted_memory=current_topic
    
    print("Extracted memory is:")
    print(extracted_memory)
    
    
    return history, extracted_memory

# Keyword functions

def remove_q_stopwords(question): # Remove stopwords from question. Not used at the moment 
    # Prepare keywords from question by removing stopwords
    text = question.lower()

    # Remove numbers
    text = re.sub('[0-9]', '', text)

    tokenizer = RegexpTokenizer(r'\w+')
    text_tokens = tokenizer.tokenize(text)
    #text_tokens = word_tokenize(text)
    tokens_without_sw = [word for word in text_tokens if not word in stopwords]

    # Remove duplicate words while preserving order
    ordered_tokens = set()
    result = []
    for word in tokens_without_sw:
        if word not in ordered_tokens:
            ordered_tokens.add(word)
            result.append(word)
     


    new_question_keywords = ' '.join(result)
    return new_question_keywords

def remove_q_ner_extractor(question):
    
    predict_out = ner_model.predict(question)



    predict_tokens = [' '.join(v for k, v in d.items() if k == 'span') for d in predict_out]

    # Remove duplicate words while preserving order
    ordered_tokens = set()
    result = []
    for word in predict_tokens:
        if word not in ordered_tokens:
            ordered_tokens.add(word)
            result.append(word)
     


    new_question_keywords = ' '.join(result).lower()
    return new_question_keywords

def apply_lemmatize(text, wnl=WordNetLemmatizer()):

    def prep_for_lemma(text):

        # Remove numbers
        text = re.sub('[0-9]', '', text)
        print(text)

        tokenizer = RegexpTokenizer(r'\w+')
        text_tokens = tokenizer.tokenize(text)
        #text_tokens = word_tokenize(text)

        return text_tokens

    tokens = prep_for_lemma(text)

    def lem_word(word):
    
        if len(word) > 3: out_word = wnl.lemmatize(word)
        else: out_word = word

        return out_word

    return [lem_word(token) for token in tokens]

def keybert_keywords(text, n, kw_model):
    tokens_lemma = apply_lemmatize(text)
    lemmatised_text = ' '.join(tokens_lemma)

    keywords_text = KeyBERT(model=kw_model).extract_keywords(lemmatised_text, stop_words='english', top_n=n, 
                                                   keyphrase_ngram_range=(1, 1))
    keywords_list = [item[0] for item in keywords_text]

    return keywords_list
    
# Gradio functions
def turn_off_interactivity(user_message, history):
        return gr.update(value="", interactive=False), history + [[user_message, None]]

def restore_interactivity():
        return gr.update(interactive=True)

def update_message(dropdown_value):
        return gr.Textbox(value=dropdown_value)

def hide_block():
        return gr.Radio(visible=False)
    
# Vote function

def vote(data: gr.LikeData, chat_history, instruction_prompt_out, model_type):
    import os
    import pandas as pd

    chat_history_last = str(str(chat_history[-1][0]) + " - " + str(chat_history[-1][1]))

    response_df = pd.DataFrame(data={"thumbs_up":data.liked,
                                        "chosen_response":data.value,
                                          "input_prompt":instruction_prompt_out,
                                          "chat_history":chat_history_last,
                                          "model_type": model_type,
                                          "date_time": pd.Timestamp.now()}, index=[0])

    if data.liked:
        print("You upvoted this response: " + data.value)
        
        if os.path.isfile("thumbs_up_data.csv"):
             existing_thumbs_up_df = pd.read_csv("thumbs_up_data.csv")
             thumbs_up_df_concat = pd.concat([existing_thumbs_up_df, response_df], ignore_index=True).drop("Unnamed: 0",axis=1, errors="ignore")
             thumbs_up_df_concat.to_csv("thumbs_up_data.csv")
        else:
            response_df.to_csv("thumbs_up_data.csv")

    else:
        print("You downvoted this response: " + data.value)

        if os.path.isfile("thumbs_down_data.csv"):
             existing_thumbs_down_df = pd.read_csv("thumbs_down_data.csv")
             thumbs_down_df_concat = pd.concat([existing_thumbs_down_df, response_df], ignore_index=True).drop("Unnamed: 0",axis=1, errors="ignore")
             thumbs_down_df_concat.to_csv("thumbs_down_data.csv")
        else:
            response_df.to_csv("thumbs_down_data.csv")