# -*- coding: utf-8 -*-

"""
News source extractor:

This script is designed to extract the content of news articles from various French media sources.
The URLs of these articles are retrieved from the `base_news` table, where articles marked with 
a `step` value of '0' are pending extraction.

To install the necessary packages:
pip install aiohttp mysql-connector-python
 
Once extracted, the content of each article is saved locally for further processing. This separation 
of content fetching and processing is intentional to optimize resource management.

The script operates in batches, processing a defined number of entries (`NB_BY_STEP`) at a time.
After extraction, the `step` value of the processed articles is updated to '1' to indicate completion.
 
For performance monitoring, the script outputs the processed article IDs, URLs, and calculates the average 
processing time per article.

Author     : Guillaume Eckendoerffer
Date       : 02-10-23
Repository : https://github.com/Eckendoerffer/TorchTrainerFlow/
             https://huggingface.co/datasets/eckendoerffer/news_fr
"""

import asyncio
import aiohttp
import time, os
from config import DB_CONFIG
from utils import create_connection, mysqli_return_number, save_to_file

NB_BY_STEP = 20
path = os.getcwd()  

async def fetch_and_save(url, id_source):
    time_start_item = time.time()
    try:
        async with aiohttp.ClientSession() as session:
            async with session.get(url, timeout=10) as response:
                byte_content = await response.read()
                try:
                    text_content = byte_content.decode('utf-8')
                except UnicodeDecodeError:
                    text_content = byte_content.decode('ISO-8859-1')

                save_to_file(f"{path}/sources/html_news/{id_source}.txt", text_content)
                time_end_item = time.time()
                print(f'{id_source}) {time_end_item-time_start_item:.5f} {url}')
    except aiohttp.client_exceptions.TooManyRedirects:
        print(f"Too many redirects for URL: {url}")
    except aiohttp.client_exceptions.ClientConnectorError:
        print(f"Failed to connect to URL: {url}")
    except Exception as e:
        print(f"Unexpected error for URL {url}: {str(e)}")

async def main():
    connection = create_connection(DB_CONFIG)
    while True:
        time_start = time.time()
        cursor = connection.cursor()
        cursor.execute(f"SELECT `id`, `url` FROM `base_news` WHERE `step`='0' ORDER BY RAND() LIMIT {NB_BY_STEP}")
        rows = cursor.fetchall()
        cursor.close()
        if not rows:
            break
        tasks = []
        for row in rows:   
            id_source, url = row
            cursor = connection.cursor()
            cursor.execute(f"UPDATE `base_news` SET `step`='1' WHERE `id`='{id_source}' LIMIT 1")
            cursor.close()
            tasks.append(fetch_and_save(url.strip(), id_source))

        await asyncio.gather(*tasks)

        nb_base = mysqli_return_number(connection, "SELECT COUNT(`id`) FROM `base_news` WHERE `step`='0'")
        time_elapsed = time.time() - time_start
        time_per_item = time_elapsed / NB_BY_STEP
        print(f"Remaining: {nb_base} - Time: {time_per_item:.3f}s/url")
        #if nb_base < 100: time.sleep(600)

    connection.close()

if __name__ == "__main__":
    asyncio.run(main())