"""
Application that builds a summary of an article.
"""

import os

import streamlit as st

from txtai.pipeline import Summary, Textractor
from txtai.workflow import UrlTask, Task, Workflow


class Application:
    """
    Main application.
    """

    def __init__(self):
        """
        Creates a new application.
        """

        textract = Textractor(paragraphs=True, minlength=100, join=True)
        summary = Summary("sshleifer/distilbart-cnn-12-6")
        self.workflow = Workflow([UrlTask(textract), Task(summary)])

    def run(self):
        """
        Runs a Streamlit application.
        """

        st.title("Article Summary")
        st.markdown("This application builds a summary of an article.")

        url = st.text_input("URL")
        if url:
            # Run workflow and get summary
            summary = list(self.workflow([url]))[0]

            # Write results
            st.write(summary)
            st.markdown("*Source: " + url + "*")


@st.cache(allow_output_mutation=True)
def create():
    """
    Creates and caches a Streamlit application.

    Returns:
        Application
    """

    return Application()


if __name__ == "__main__":
    os.environ["TOKENIZERS_PARALLELISM"] = "false"

    # Create and run application
    app = create()
    app.run()