# url handlers

import re, time, json, logging, hashlib, base64, asyncio

## markdown 是处理日志文本的一种格式语法
import markdown2
from aiohttp import web
from coroweb import get, post

## 分页管理以及调取API时的错误信息
from apis import Page, APIValueError, APIResourceNotFoundError,APIError
from models import User, Comment, Blog, next_id
from config import configs

COOKIE_NAME = 'awesession'
_COOKIE_KEY = configs.session.secret

def user2cookie(user, max_age):
    # build cookie string by: id-expires-sha1
    expires = str(int(time.time() + max_age))
    s = '%s-%s-%s-%s' % (user.id, user.passwd, expires, _COOKIE_KEY)
    L = [str(user.id), expires, hashlib.sha1(s.encode('utf-8')).hexdigest()]
    return '-'.join(L)

@get('/')
async def index(request):

    # users = await User.findAll()
    summary = 'XXXXXXXXX啦啦啦啦啦啦啦'
    blogs = [
        Blog(id='1', name='AAAAA', summary=summary, created_at=time.time() - 1200),
        Blog(id='2', name='BBBBB', summary=summary, created_at=time.time() - 3600),
        Blog(id='3', name='CCCCC', summary=summary, created_at=time.time() - 7200)
    ]
    return {
        '__template__': 'blogs.html',
        'blogs': blogs,
        # '__user__': request.__user__
    }
@get('/api/users')
async def api_get_users():
    users = await User.findAll(orderBy='created_at desc')
    for u in users:
        u.passwd = '******'
    return dict(users=users)
@get('/register')
def register():
    return {
       '__template__': 'register.html'
    }
## 处理登录页面URL
@get('/signin')
def signin():
    return {
        '__template__': 'signin.html'
    }

@get('/signout')
def signout(request):
    referer = request.headers.get('Referer')
    r = web.HTTPFound(referer or '/')
    r.set_cookie(COOKIE_NAME, '-deleted-', max_age=0, httponly=True)
    logging.info('user signed out.')
    return r

## 用户登录验证API
@post('/api/authenticate')
async def authenticate(*, email, passwd):
    if not email:
        raise APIValueError('email', 'Invalid email.')
    if not passwd:
        raise APIValueError('passwd', 'Invalid password.')
    users = await User.findAll('email=?', [email])
    if len(users) == 0:
        raise APIValueError('email', 'Email not exist.')
    user = users[0]
    # check passwd:
    sha1 = hashlib.sha1()
    sha1.update(user.id.encode('utf-8'))  #AttributeError: 'int' object has no attribute 'encode'
    sha1.update(b':')
    sha1.update(passwd.encode('utf-8'))
    # if user.passwd != sha1.hexdigest():
    #     raise APIValueError('passwd', 'Invalid password.')
    # authenticate ok, set cookie:
    r = web.Response()
    r.set_cookie(COOKIE_NAME, user2cookie(user, 86400), max_age=86400, httponly=True)
    user.passwd = '******'
    r.content_type = 'application/json'
    r.body = json.dumps(user, ensure_ascii=False).encode('utf-8')
    return r

_RE_EMAIL = re.compile(r'^[a-z0-9\.\-\_]+\@[a-z0-9\-\_]+(\.[a-z0-9\-\_]+){1,4}$')
_RE_SHA1 = re.compile(r'^[0-9a-f]{40}$')
## 用户注册API
@post('/api/users')
async def api_register_user(*, email, name, passwd):
    if not name or not name.strip():
        raise APIValueError('name')
    if not email or not _RE_EMAIL.match(email):
        raise APIValueError('email')
    if not passwd or not _RE_SHA1.match(passwd):
        raise APIValueError('passwd')
    users = await User.findAll('email=?', [email])
    if len(users) > 0:
        raise APIError('register:failed', 'email', 'Email is already in use.')
    uid = next_id()
    sha1_passwd = '%s:%s' % (uid, passwd)
    user = User(id=uid, name=name.strip(), email=email, passwd=hashlib.sha1(sha1_passwd.encode('utf-8')).hexdigest(), image='http://www.gravatar.com/avatar/%s?d=mm&s=120' % hashlib.md5(email.encode('utf-8')).hexdigest())
    await user.save()
    # make session cookie:
    r = web.Response()
    r.set_cookie(COOKIE_NAME, user2cookie(user, 86400), max_age=86400, httponly=True)
    user.passwd = '******'
    r.content_type = 'application/json'
    r.body = json.dumps(user, ensure_ascii=False).encode('utf-8')
    return r


# 解密cookie:
@asyncio.coroutine
def cookie2user(cookie_str):
    '''
    Parse cookie and load user if cookie is valid.
    '''
    if not cookie_str:
        return None
    try:
        L = cookie_str.split('-')
        if len(L) != 3:
            return None
        uid, expires, sha1 = L
        if int(expires) < time.time():
            return None
        user = yield from User.find(uid)
        if user is None:
            return None
        s = '%s-%s-%s-%s' % (uid, user.passwd, expires, _COOKIE_KEY)
        if sha1 != hashlib.sha1(s.encode('utf-8')).hexdigest():
            logging.info('invalid sha1')
            return None
        user.passwd = '******'
        return user
    except Exception as e:
        logging.exception(e)
        return None

@asyncio.coroutine
def auth_factory(app, handler):
    @asyncio.coroutine
    def auth(request):
        logging.info('check user: %s %s' % (request.method, request.path))
        request.__user__ = None
        cookie_str = request.cookies.get(COOKIE_NAME)
        if cookie_str:
            user = yield from cookie2user(cookie_str)
            if user:
                logging.info('set current user: %s' % user.email)
                request.__user__ = user
        return (yield from handler(request))
    return auth