import json
import os
import tarfile
import time
import urllib.request
import shutil

repo_url = "https://api.github.com/repos/datahub-project/static-assets"


def download_file(url, destination):
    with urllib.request.urlopen(url) as response:
        with open(destination, "wb") as f:
            while True:
                chunk = response.read(8192)
                if not chunk:
                    break
                f.write(chunk)


def fetch_urls(
    repo_url: str, folder_path: str, file_format: str, active_versions: list, max_retries=3, retry_delay=5
):
    api_url = f"{repo_url}/contents/{folder_path}"
    for attempt in range(max_retries + 1):
        try:
            response = urllib.request.urlopen(api_url)
            if response.status == 403 or (500 <= response.status < 600):
                raise Exception(f"HTTP Error {response.status}: {response.reason}")
            data = response.read().decode("utf-8")
            urls = [
                file["download_url"]
                for file in json.loads(data)
                if file["name"].endswith(file_format) and any(version in file["name"] for version in active_versions)
            ]
            print(urls)
            return urls
        except Exception as e:
            if attempt < max_retries:
                print(f"Attempt {attempt + 1}/{max_retries}: {e}")
                time.sleep(retry_delay * 2**attempt)
            else:
                print("Max retries reached. Unable to fetch data.")
                raise


def extract_tar_file(destination_path):
    with tarfile.open(destination_path, "r:gz") as tar:
        tar.extractall()
    os.remove(destination_path)

def get_active_versions():
    # read versions.json
    with open("versions.json") as f:
        versions = json.load(f)
    return versions

def clear_directory(directory):
    if os.path.exists(directory):
        shutil.rmtree(directory)
    os.makedirs(directory)

def download_versioned_docs(folder_path: str, destination_dir: str, file_format: str):
    clear_directory(destination_dir)  # Clear the directory before downloading

    active_versions = get_active_versions()
    urls = fetch_urls(repo_url, folder_path, file_format, active_versions)

    for url in urls:
        filename = os.path.basename(url)
        destination_path = os.path.join(destination_dir, filename)

        version = ".".join(filename.split(".")[:3])
        extracted_path = os.path.join(destination_dir, version)
        print("extracted_path", extracted_path)
        if os.path.exists(extracted_path):
            print(f"{extracted_path} already exists, skipping downloads")
            continue
        try:
            download_file(url, destination_path)
            print(f"Downloaded {filename} to {destination_dir}")
            if file_format == ".tar.gz":
                extract_tar_file(destination_path)
        except urllib.error.URLError as e:
            print(f"Error while downloading {filename}: {e}")
            continue


def main():
    download_versioned_docs(
        folder_path="versioned_docs",
        destination_dir="versioned_docs",
        file_format=".tar.gz",
    )
    download_versioned_docs(
        folder_path="versioned_sidebars",
        destination_dir="versioned_sidebars",
        file_format=".json",
    )


if __name__ == "__main__":
    main()