import streamlit as st
from transformers import pipeline
import time

# Load selected model's pipeline
@st.cache_resource
def load_pipeline(model_name):
    if model_name == 'BART':
        return pipeline("summarization", model="facebook/bart-large-cnn")
    elif model_name == 'T5':
        return pipeline("summarization", model="t5-large")
    elif model_name == 'Pegasus':
        return pipeline("summarization", model="google/pegasus-cnn_dailymail")

# Streamlit app layout
st.title("Text Summarization with Pre-trained Models (BART, T5, Pegasus)")

text_input = st.text_area("Enter text to summarize:")

if text_input:
    # Display word count of input text
    word_count = len(text_input.split())
    st.write(f"**Word Count:** {word_count}")

    model_choice = st.selectbox("Choose a model:", ['BART', 'T5', 'Pegasus'])

    if st.button("Generate Summary"):
        with st.spinner(f"Generating summary using {model_choice}..."):
            start_time = time.time()
            summarizer = load_pipeline(model_choice)
            summary = summarizer(text_input, max_length=150, min_length=50, length_penalty=2.0, num_beams=4, early_stopping=True)[0]['summary_text']
            end_time = time.time()
            summary_word_count = len(summary.split())

        st.subheader(f"Summary using {model_choice}")
        st.write(summary.replace('<n>', ''))
        st.write(f"**Summary Word Count:** {summary_word_count}")
        st.write(f"**Time Taken:** {end_time - start_time:.2f} seconds")
else:
    st.error("Please enter text to summarize.")