"""A script to help create new blog posts by asking the user some questions and
then creating a new .rst file accordingly.

"""
import datetime
import os
import pwd
import re
import subprocess


POST = """\
{title}
{title_under}

:date: {date}
:tags: {tags}
:slug: {slug}
:author: {author}

"""


def slugify(s):
    """Return a slug from the string s."""

    slug = s.lower()

    # convert ellipses to spaces
    slug = re.sub(r'\.{2,}', ' ', slug)

    # flatten everything non alpha or . into a single -
    slug = re.sub(r'[^0-9a-zA-Z\.]+', '-', slug)

    # trim off leading/trailing -
    slug = re.sub(r'^-+|-+$', '', slug)
    return slug


def main():

    title = raw_input("Blog title: ")
    title_under = '#' * len(title)

    # Usually takes me about an hour to write a blog post:
    anticipated_date = datetime.datetime.now() + datetime.timedelta(hours=1)
    default_date = anticipated_date.strftime('%Y-%m-%d %H:%M')
    date_str = raw_input("Publish date [{}]: ".format(default_date))
    date_str = date_str if date_str else default_date

    tags = raw_input("Tags (comma separated): ")

    default_slug = slugify(title)
    slug = raw_input("Slug [{}]: ".format(default_slug))
    slug = slug if slug else default_slug

    # Author; yes I could just hardcode my name here... ;)
    user = os.environ.get('USER', '')
    if user:
        user = pwd.getpwnam(user)[4].split(',')[0]

    default_author = user
    author = raw_input('Author [{}]: '.format(default_author))
    author = author if author else default_author

    post = POST.format(title=title, title_under=title_under, date=date_str,
            tags=tags, slug=slug, author=author)

    # Create a file for the new post.
    # This is all specific to my convention of put posts under a category
    # directory and having the first 3 characters in the filename be a number
    # (000-999).
    category = raw_input('Category [Coding]: ')
    category = category if category else 'Coding'

    post_dir = os.path.join('content', category)
    posts = sorted(os.listdir(post_dir))
    if posts:
        last_post_num = int(posts[-1][:3])
        num = last_post_num + 1
    else:
        num = 0

    new_name = '{num:03}-{slug}.rst'.format(num=num, slug=slug)
    new_path = os.path.join('content', category, new_name)

    # Write file:
    with open(new_path, 'w') as fp:
        fp.write(post)

    # Launch editor if set
    editor = os.environ.get('VISUAL', os.environ.get('EDITOR'))
    if editor:
        subprocess.call([editor, new_path])


if __name__ == '__main__':
    main()