#!/usr/bin/env python3
"""
Fetch contributors data from Github using their API, convert it to structured
JSON data for the /team page contributors section.
"""
import os
import sys

sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))
from scripts.lib.setup_path import setup_path

setup_path()

import argparse
import logging
from datetime import date
from random import randrange
from time import sleep
from typing import Dict, List, Optional, Union

from typing_extensions import TypedDict

os.environ['DJANGO_SETTINGS_MODULE'] = 'zproject.settings'
import django

django.setup()

import json

import requests
from django.conf import settings

from zerver.lib.avatar_hash import gravatar_hash
from zproject.config import get_secret

duplicate_commits_file = os.path.join(os.path.dirname(__file__), 'duplicate_commits.json')

parser = argparse.ArgumentParser()
parser.add_argument('--max-retries', type=int, default=10,
                    help='Number of times to retry fetching data from Github')
args = parser.parse_args()

class ContributorsJSON(TypedDict):
    date: str
    contributors: List[Dict[str, Union[int, str]]]

class Contributor(TypedDict):
    avatar_url: Optional[str]
    contributions: int
    login: Optional[str]
    email: Optional[str]
    name: Optional[str]

logger = logging.getLogger('zulip.fetch_contributors_json')

def fetch_contributors(repo_name: str, max_retries: int) -> List[Contributor]:
    contributors: List[Contributor] = []
    retry_attempts = 0
    page_index = 1

    api_link = f"https://api.github.com/repos/zulip/{repo_name}/contributors?anon=1"
    certificates = os.environ.get('CUSTOM_CA_CERTIFICATES')

    headers: Dict[str, str] = {}
    personal_access_token = get_secret('github_personal_access_token')
    if personal_access_token is not None:
        headers = {"Authorization": f"token {personal_access_token}"}

    while True:
        response: requests.Response = requests.get(f"{api_link}&page={page_index}", verify=certificates, headers=headers)
        if response.status_code == 200:
            data = response.json()
            if len(data) == 0:
                return contributors
            contributors.extend(data)
            retry_attempts = 0
            page_index += 1
        else:
            retry_attempts += 1
            if retry_attempts > args.max_retries:
                logger.warning("Failed retries fetching contributors data from Github.")
                sys.exit(1)

            sleep_time = randrange(0, min(64, 2**retry_attempts))
            sleep(sleep_time)

def write_to_disk(json_data: ContributorsJSON, out_file: str) -> None:
    with open(out_file, 'w') as f:
        json.dump(json_data, f, indent=2, sort_keys=True)
        f.write("\n")

def update_contributor_data_file() -> None:
    # This list should hold all repositories that should be included in
    # the total count, including those that should *not* have tabs on the team
    # page (e.g. if they are deprecated).
    repo_names = ['zulip', 'zulip-desktop', 'zulip-mobile', 'python-zulip-api', 'zulip-js', 'zulipbot',
                  'zulip-terminal', 'zulip-ios-legacy', 'zulip-android']

    data: ContributorsJSON = dict(date=str(date.today()), contributors=[])
    contributor_username_to_data: Dict[str, Dict[str, Union[str, int]]] = {}

    for repo_name in repo_names:
        contributors = fetch_contributors(repo_name, args.max_retries)
        for contributor in contributors:
            username = contributor.get('login') or contributor.get('email')
            assert(username is not None)
            if username in contributor_username_to_data:
                contributor_username_to_data[username][repo_name] = contributor['contributions']
            else:
                contributor_username_to_data[username] = {
                    repo_name: contributor['contributions']
                }

                avatar_url = contributor.get('avatar_url')
                if avatar_url is not None:
                    contributor_username_to_data[username]['avatar'] = avatar_url

                email = contributor.get('email')
                if email is not None:
                    contributor_username_to_data[username]["email"] = email
                    hash_key = gravatar_hash(email)
                    gravatar_url = f"https://secure.gravatar.com/avatar/{hash_key}?d=identicon"
                    contributor_username_to_data[username]['avatar'] = gravatar_url

                login = contributor.get('login')
                if login is not None:
                    contributor_username_to_data[username]["github_username"] = login

                name = contributor.get('name')
                if name is not None:
                    contributor_username_to_data[username]["name"] = name

    # remove duplicate contributions count
    # find commits at the time of split and subtract from zulip-server
    with open(duplicate_commits_file) as f:
        duplicate_commits = json.load(f)
        for committer in duplicate_commits:
            if committer in contributor_username_to_data and contributor_username_to_data[committer].get('zulip'):
                total_commits = contributor_username_to_data[committer]['zulip']
                assert isinstance(total_commits, int)
                duplicate_commits_count = duplicate_commits[committer]
                original_commits = total_commits - duplicate_commits_count
                contributor_username_to_data[committer]['zulip'] = original_commits

    data['contributors'] = list(contributor_username_to_data.values())
    write_to_disk(data, settings.CONTRIBUTOR_DATA_FILE_PATH)

if __name__ == "__main__":
    update_contributor_data_file()