import os
import time
import pdfplumber
import docx
import nltk
import gradio as gr
from langchain.embeddings import HuggingFaceEmbeddings
from langchain.vectorstores import FAISS
from langchain.text_splitter import RecursiveCharacterTextSplitter, SentenceTextSplitter
from sentence_transformers import SentenceTransformer
from transformers import AutoTokenizer
from nltk import sent_tokenize
from typing import List, Tuple
from transformers import AutoModel, AutoTokenizer

# Ensure nltk sentence tokenizer is downloaded
nltk.download('punkt')

FILES_DIR = './files'

# Supported embedding models
MODELS = {
    'e5-base': "danielheinz/e5-base-sts-en-de",
    'multilingual-e5-base': "multilingual-e5-base",
    'paraphrase-miniLM': "paraphrase-multilingual-MiniLM-L12-v2",
    'paraphrase-mpnet': "paraphrase-multilingual-mpnet-base-v2",
    'gte-large': "gte-large",
    'gbert-base': "gbert-base"
}

class FileHandler:
    @staticmethod
    def extract_text(file_path):
        ext = os.path.splitext(file_path)[-1].lower()
        if ext == '.pdf':
            return FileHandler._extract_from_pdf(file_path)
        elif ext == '.docx':
            return FileHandler._extract_from_docx(file_path)
        elif ext == '.txt':
            return FileHandler._extract_from_txt(file_path)
        else:
            raise ValueError(f"Unsupported file type: {ext}")

    @staticmethod
    def _extract_from_pdf(file_path):
        with pdfplumber.open(file_path) as pdf:
            return ' '.join([page.extract_text() for page in pdf.pages])

    @staticmethod
    def _extract_from_docx(file_path):
        doc = docx.Document(file_path)
        return ' '.join([para.text for para in doc.paragraphs])

    @staticmethod
    def _extract_from_txt(file_path):
        with open(file_path, 'r', encoding='utf-8') as f:
            return f.read()

class EmbeddingModel:
    def __init__(self, model_name, max_tokens=None):
        self.model = HuggingFaceEmbeddings(model_name=model_name)
        self.max_tokens = max_tokens

    def embed(self, text):
        return self.model.embed_documents([text])

def process_files(model_name, split_strategy, chunk_size=500, overlap_size=50, max_tokens=None):
    # File processing
    text = ""
    for file in os.listdir(FILES_DIR):
        file_path = os.path.join(FILES_DIR, file)
        text += FileHandler.extract_text(file_path)

    # Split text
    if split_strategy == 'sentence':
        splitter = SentenceTextSplitter(chunk_size=chunk_size, chunk_overlap=overlap_size)
    else:
        splitter = RecursiveCharacterTextSplitter(chunk_size=chunk_size, chunk_overlap=overlap_size)
    
    chunks = splitter.split_text(text)
    model = EmbeddingModel(MODELS[model_name], max_tokens=max_tokens)
    embeddings = model.embed(text)
    
    return embeddings, chunks

def search_embeddings(query, model_name, top_k):
    model = HuggingFaceEmbeddings(model_name=MODELS[model_name])
    embeddings = model.embed_query(query)
    return embeddings

def calculate_statistics(embeddings):
    # Return time taken, token count, etc.
    return {"tokens": len(embeddings), "time_taken": time.time()}

# Gradio frontend
def upload_file(file, model_name, split_strategy, chunk_size, overlap_size, max_tokens, query, top_k):
    with open(os.path.join(FILES_DIR, file.name), "wb") as f:
        f.write(file.read())

    # Process files and get embeddings
    embeddings, chunks = process_files(model_name, split_strategy, chunk_size, overlap_size, max_tokens)

    # Perform search
    results = search_embeddings(query, model_name, top_k)

    # Calculate statistics
    stats = calculate_statistics(embeddings)
    
    return {"results": results, "stats": stats}

# Gradio interface
iface = gr.Interface(
    fn=upload_file,
    inputs=[
        gr.File(label="Upload File"),
        gr.Dropdown(choices=list(MODELS.keys()), label="Embedding Model"),
        gr.Radio(choices=["sentence", "recursive"], label="Split Strategy"),
        gr.Slider(100, 1000, step=100, value=500, label="Chunk Size"),
        gr.Slider(0, 100, step=10, value=50, label="Overlap Size"),
        gr.Slider(50, 500, step=50, value=200, label="Max Tokens"),
        gr.Textbox(label="Search Query"),
        gr.Slider(1, 10, step=1, value=5, label="Top K")
    ],
    outputs="json"
)

iface.launch()