"""Give each work a tile size derived from what it actually contains.

A uniform grid gives a ten-hour festival set and a two-line workshop note the
same visual weight, which is both untrue and the most dated thing about the
original layout. Weight is taken from evidence already in the entry: how much
imagery survived, whether there is video, and how much was written about it.
"""
import re

from pelican import signals

IMG = re.compile(r'<img\b', re.I)
VID = re.compile(r'<(?:iframe|embed|video)\b', re.I)


def _weigh(content):
    if content.__class__.__name__ != 'Article':
        return
    body = getattr(content, '_content', '') or ''
    imgs = len(IMG.findall(body))
    vids = len(VID.findall(body))
    words = len(re.sub(r'<[^>]+>', ' ', body).split())

    score = imgs + vids * 4 + words / 90.0
    # a work with no surviving image cannot carry a large tile: it would be a
    # big rectangle of static, which reads as a fault rather than a choice
    if content.metadata.get('thumb_missing') or not content.metadata.get('thumb'):
        size = 'sm'
    elif score >= 9:
        size = 'lg'
    elif score >= 4.5:
        size = 'md'
    else:
        size = 'sm'
    content.metadata['tilesize'] = size
    content.metadata['tilescore'] = round(score, 1)


def register():
    signals.content_object_init.connect(_weigh)