#!/usr/bin/env python3

from os import environ
from typing import Optional, Tuple
from datetime import datetime
from redis import Redis
from hashlib import sha256
from functools import reduce

s = datetime.now()
NO_REMOTE_IDENTITY_MSG = """User identity hash not available.
In MeshChat: use the fingerprint button in the top right to send the identification information.
In NomadNet: Save node, click on it, go to <Info> and select "Identify when connecting"."""

FORBIDDEN_INPUT = [
    "[",
    "`",
    "\n"
]

ADMIN_IDENTITIES = [
    "e6c72573bb91d48338dbcc57d0223b81",
    "70c9608c9a0f4ae895f7fab406554e1c"
]
BGCOLOR = "`F333`BDDD"

def is_admin() -> bool:
    remote_identity = environ.get("remote_identity", None)
    if remote_identity is None:
        return False
    return remote_identity in ADMIN_IDENTITIES

def sanitize_input(text: str) -> str:
    return reduce(lambda a, b: a.replace(b, ""), FORBIDDEN_INPUT, text)

def check_password(password: str) -> bool:
    expected = '34a77e61000b2ba1f56201332ef64d93f9cdc60e63ab48bc255102586ef7e592'
    gotten = sha256(f"hswrosalt{password}".encode('utf-8'), usedforsecurity=True).hexdigest()
    return expected == gotten

def check_name(username: str) -> bool:
    if len(username) >= 16:
        return False
    return all(map(lambda c: c.isalnum(), username))

def get_login_info() -> Tuple[Optional[str], Optional[str]]:
    """Returns [login_name, error]"""
    remote_identity = environ.get("remote_identity", None)
    if remote_identity is None:
        return (None, NO_REMOTE_IDENTITY_MSG)
    r = Redis(host='localhost', port=6379, db=0)
    login = r.get(f'login_info_{remote_identity}')
    if login is None:
        return (None, None)
    return (login.decode('utf-8'), None)

def login(username: str) -> Optional[str]:
    """Returns err"""
    remote_identity = environ.get("remote_identity", None)
    if remote_identity is None:
        return NO_REMOTE_IDENTITY_MSG
    if not check_name(username):
        return "Username should only contain alphanumeric characters and have at most 16 characters."
    r = Redis(host='localhost', port=6379, db=0)
    r.set(f'login_info_{remote_identity}', username)
    return None

def logout():
    remote_identity = environ.get("remote_identity", None)
    if remote_identity is None:
        return
    r = Redis(host='localhost', port=6379, db=0)
    r.delete(f'login_info_{remote_identity}')
        

def login_button() -> str:
    l = get_login_info()
    if l[0] is None:
        return "[`[Identify`:/page/login.mu`]]"
    else:
        return f"Welcome, {l[0]} | [`[Forget`:/page/logout.mu`]]"

def header(title: Optional[str] = None):
    if title is None:
        title = ""
    else:
        title = ": `i" + title
    print(f"""`F000`BFB1
`c
-*abc
`r {login_button()}
`l `!Hackerspace`!Wrocław{title}
`a

-_                       
`a
``
`FEEE`B333
`c

`l  `[Home`:/page/index.mu]`  | `[Status`:/page/status.mu]`  | `[Shoutbox`:/page/chat.mu]`
   
`a
``
{BGCOLOR}
""")

def reset_colors() -> str:
    print(BGCOLOR)

def footer():
    print(f"{BGCOLOR}`r Rendered in: {(datetime.now()-s).total_seconds()}s")
    print(f"{datetime.now()}")

if __name__ == "__main__":
    pass