import requests
import datetime
import model
import config





# file_size if byte
# longest_time seconds
def download_file(chunk_size=4 * 1024, file_size=100 * 1024 * 1024, longest_time=60):
    execution_datetime=datetime.datetime.now()
    print("Download at {time}".format(time=execution_datetime))
    servers = config.get_servers()
    for server_name in servers:
        server = servers[server_name]
        url = server["url"]
        server_name = server["name"]
        chunk_read = 0
        s_time = datetime.datetime.now()
        print('start time:{s_time}'.format(s_time=s_time))
        duration = longest_time
        try:
            with requests.get(url, stream=True, timeout=longest_time) as r:
                for chunk in r.iter_content(chunk_size):
                    if chunk:
                        chunk_read += len(chunk)
                        e_time = datetime.datetime.now()
                        duration = (e_time - s_time).total_seconds()
                        if chunk_read >= file_size:
                            break
                        if duration >= longest_time:
                            print(
                                "{server} longer than {longest_time} seconds. Stopped.".format(
                                    longest_time=longest_time, server=server_name
                                )
                            )
                            break
            print('end time:{e_time}'.format(e_time=e_time))
            speed = chunk_read / duration / 1024 / 1024 * 8  # mega bit
            model.add_record(execution_datetime,server_name, speed)
            print("{server}:{speed} Mbit/s".format(server=server_name, speed=speed))
        except requests.exceptions.Timeout as e:
            print(
                "timeout before wait {timeout} seconds. Error:{err}".format(
                    err=str(e), timeout=longest_time
                )
            )