'''
Copyright (c) linlin152@foxmail.com. All rights reserved.
License: Apache 2.
'''
import sys
import time
import json
import os

import pychrome


browser = pychrome.Browser(url="http://127.0.0.1:9222")


def get_id(node):
    attrs = get_attrs(node, t='attributes')
    if 'action' not in attrs:
        print(attrs)
        return None
    index = attrs.index('action')
    if index < 0:
        return None

    url = attrs[index+1]
    if 'follow' not in url:
        return None

    return url.split('target=', 1)[-1]


def get_attrs(node, t):
    attrs = []
    if 'children' in node:
        for child in node['children']:
            attrs.extend(get_attrs(child, t))

    attr = node.get(t)
    if not attr:
        return attrs
    if isinstance(attr, list):
        attrs.extend(attr)
    elif isinstance(attr, str):
        attrs.append(attr)
    return attrs


def is_wanted(node, locations):
    values = get_attrs(node, 'nodeValue')
    for loc in locations:
        for value in values:
            if loc.lower() in value.lower():
                return True

    return False


def get_by_class(root, klass):
    if isinstance(root, dict):
        attrs = root.get('attributes')
        if attrs and 'class' in attrs and klass in attrs:
            return [root]
    else:
        return []

    nodes = []
    if 'children' not in root:
        return []

    for child in root['children']:
        ns = get_by_class(child, klass)
        nodes.extend(ns)

    return nodes

def get_followers(root):
    klass = 'd-table table-fixed col-12 width-full py-4 border-bottom color-border-muted'
    users = []
    fs = get_by_class(root, klass)
    for f in fs:
        if is_wanted(f, locations=['shenzhen', 'chengdu']):
            user = get_id(f)
            if not user:
                continue
            email = get_email(user)
            time.sleep(5)
            if not email:
                continue
            users.append({'id': user, 'email': email})

    return users

def get_all_followers(user, total, timeout=5, offset=1):
    res = []
    for page in range(offset, total//50+1):
        print("Page %s" % page)
        url = "https://github.com/{}?page={}&tab=followers".format(user, page)
        doc = get_doc(url)
        if not doc:
            continue
        tmp = get_followers(doc['root'])
        if tmp:
            print("found: %s" % tmp)
        res.extend(tmp)
        print("Page %s done, Sleep 20s" % page)
        time.sleep(20)

    return res

def get_doc(url, timeout=3):
    tab = browser.new_tab()
    tab.start()
    try:
        res = tab.Page.navigate(url=url, _timeout=5)
    except  Exception as ex:
        print("Found exception")
        print(ex)
        tab.stop()
        browser.close_tab(tab)
        return None
    tab.wait(timeout)
    doc = tab.DOM.getDocument(depth=-1, pierce=True)
    tab.stop()
    browser.close_tab(tab)
    return doc

def get_email(user):
    url = 'https://github.com/{}'.format(user)
    doc = get_doc(url)
    if not doc:
        return None
    email = get_by_class(doc['root'], 'u-email Link--primary ')
    if not email:
        return None
    ret = get_attrs(email[0], 'attributes')
    return ret[-1].split('mailto:')[-1]


def add_newly(db, new, user):

    dict_db = {}

    for item in db:
        dict_db[item['id']] = item

    added = []

    t = time.strftime("%Y-%m-%d %H:%M:%S", time.localtime())
    for r in new:
        if r['id'] in dict_db:
            fs = dict_db[r['id']]['following']
            if user not in fs:
                fs.append(user)
            continue
        r['time'] = t
        r['following'] = [user]
        db.append(r)
        added.append(r)

    return added


def update2disk(res, user, filename="db.json"):

    db = []
    if os.path.exists(filename):
        with open(filename, 'r') as f:
            db = json.load(f)

    added = add_newly(db, res, user)
    print("Found %d newly added." % len(added))

    with open(filename, 'w') as f:
        json.dump(db, f, indent=2)


if __name__ == '__main__':
    user = sys.argv[1]
    count = int(sys.argv[2])
    offset = 1
    if len(sys.argv) == 4:
        offset = int(sys.argv[3])
    res = get_all_followers(user, count, offset=offset)
    update2disk(res, user)