import datetime as dt

from django.templatetags.static import static
from django.urls import reverse

from jinja2 import Environment

from typing import Any, Optional

GLOBAL_STYLES = {
    'action-button': 'db ba b--black white f5 bg-dark-blue bold pa1 ph3 pointer hover-bg-blue bg-animate',
}

def duration(seconds: Optional[float]):
    if seconds is None:
        return '-'

    secs = int(seconds % 60)
    mins = int((seconds // 60) % 60)
    hours = int(seconds // 3600)

    if hours > 0:
        return f'{hours:d}:{mins:02d}:{secs:02d}'
    else:
        return f'{mins:d}:{secs:02d}'

def distance(meters: Optional[float]):
    if meters is None:
        return '-'
    return f'{meters/1000:0.1f} km'

def isodate(d: Optional[dt.datetime]) -> str:
    if d is None:
        return '-'
    return d.strftime('%Y-%m-%d')

def isotime(d: Optional[dt.datetime]) -> str:
    if d is None:
        return '-'
    return d.strftime('%H:%M')

def date(d: Optional[dt.datetime]) -> str:
    if d is None:
        return '-'
    return d.strftime('%d.\u202f%m.\u202f%Y')

def datetime(d: Optional[dt.datetime]) -> str:
    if d is None:
        return '-'
    return d.strftime('%d.\u202f%m.\u202f%Y\u202f%H:%M')

def optional_int(x: Optional[Any]) -> str:
    if x is None:
        return '-'
    return str(round(x))

def environment(**options):
    env = Environment(**options)
    env.globals.update({
        'now': dt.datetime.now,
        'static': static,
        'url': reverse,
        'styles': GLOBAL_STYLES,
    })
    env.filters.update({
        'date': date,
        'datetime': datetime,
        'distance': distance,
        'duration': duration,
        'isodate': isodate,
        'isotime': isotime,
        'optional_int': optional_int,
    })
    return env