import json
import os
import time

import click
import requests


class AuthToken:
    def __init__(self):
        self.tokenfile = "token.json"
        
    def save_oauth_token(self, token):
        tokenfile_content = {}
        # check if file extists
        if os.path.exists(self.tokenfile):
            with open(self.tokenfile, "r") as f:
                tokenfile_content = json.load(f)
        tokenfile_content["oauth_token"] = token
        with open(self.tokenfile, "w") as f:
            json.dump(tokenfile_content, f)

    def get_oauth_token(self):
        # check if token in tokenfile
        if os.path.exists(self.tokenfile):
            with open(self.tokenfile, "r") as f:
                tokendict = json.load(f)
                if "oauth_token" in tokendict:
                    return tokendict["oauth_token"]
        
        # if not, check if the github copilot extension is installed on the system
        path = os.path.expanduser("~/.config/github-copilot/hosts.json")
        if os.path.exists(path):
            with open(path, "r") as f:
                hosts = json.load(f)
                if "github.com" in hosts:
                    token = hosts["github.com"]["oauth_token"]
                    self.save_oauth_token(token)
                    return token

        # if not, ask the user to enter the token
        click.echo("Please enter your github access token (can be found in ~/.config/github-copilot/hosts.json):")
        token = click.prompt("Token", type=str)
        self.save_oauth_token(token)
        return token

    def save_github_api_token(self, token: str, expires_at):
        tokenfile_content = {}
        # check if file extists
        if os.path.exists(self.tokenfile):
            with open(self.tokenfile, "r") as f:
                tokenfile_content = json.load(f)
        tokenfile_content["token"] = token
        tokenfile_content["expires_at"] = expires_at
        with open(self.tokenfile, "w") as f:
            json.dump(tokenfile_content, f)

    def request_github_api_token(self):
        # get the oauth token
        oauth_token = self.get_oauth_token()

        headers = {
            'Authorization': f"Bearer {oauth_token}",
        }
        response = requests.get('https://api.github.com/copilot_internal/v2/token', headers=headers)
        
        if response.status_code != 200:
            return None

        token = response.json()
        self.save_github_api_token(token["token"], token["expires_at"])
        return token["token"]


    def get_github_api_token(self):
        # check if token in tokenfile
        if os.path.exists(self.tokenfile):
            with open(self.tokenfile, "r") as f:
                tokendict = json.load(f)
                if "token" in tokendict and "expires_at" in tokendict:
                    if tokendict["expires_at"] > time.time():
                        return tokendict["token"]
        
        # request new api token
        return self.request_github_api_token()