import os

from datasets.download.download_config import DownloadConfig
from datasets.utils.file_utils import cached_path
from datasets.utils.hub import hf_hub_url


def get_readme_path(dataset_name):
    readme_path = hf_hub_url(dataset_name, "README.md")
    return cached_path(readme_path, download_config=DownloadConfig())


def update_readme(dataset_name, subreddit, date_to_fetch):
    path = get_readme_path(dataset_name=dataset_name)
    readme_text = f"""
    # Dataset Name
    {dataset_name}

    ## Update Frequency
    The dataset is updated daily and covers the period from `{os.environ["START_DATE"]}` to {date_to_fetch}

    ## Dataset Overview
    The goal is to have an open dataset of `{subreddit}` submissions. This has been taken from the Pushshift API.

    ## Data Collection
    This has been collected with sequential calls that follow the pagination of the pushshift request. 

    ## Attribution
    Data sourced from the Pushshift API.
    """

    append_readme(path=path, readme_text=readme_text)
    return readme_text


def append_readme(path, readme_text):
    generated_below_marker = "--- Generated Below ---"
    with open(path, "r") as file:
        content = file.read()

    if generated_below_marker in content:
        index = content.index(generated_below_marker) + len(generated_below_marker)
        content = content[:index] + "\n" + readme_text + "\n" + content[index:]
    else:
        content += "\n" + generated_below_marker + "\n" + readme_text + "\n"

    with open(path, "w") as file:
        file.write(content)