#!/usr/bin/env python3

from collections import namedtuple, Counter
from datetime import date
from glob import glob
from itertools import chain
from jinja2 import Environment, FileSystemLoader
from markdown import markdown
from markupsafe import Markup
from operator import attrgetter
from subprocess import call as run
from pygments.formatters import HtmlFormatter
import meta
import os

CONTENT = './content'
OUTPUT = './output'
KWORDS = { 'Tomasz Kramkowski', 'the-tk', 'blog', 'projects', 'TK', 'Arch-TK' }
ERRORS = {
    403: "Forbidden",
    404: "File Not Found",
    500: "Internal Server Error",
    502: "Bad Gateway",
    503: "Service Unavailable",
    504: "Gateway Timeout",
}

md = lambda s: Markup(markdown(s, extensions=['fenced_code', 'codehilite', 'toc']))

File = namedtuple('File', 'content date slug ext')
def parse(path, has_date=False):
    with open(path) as f:
        content = meta.parse(f.read())
    slug, ext = os.path.splitext(os.path.split(path)[1])
    if has_date:
        y, m, d, slug = slug.split('-', 3)
        dat = date(int(y), int(m), int(d))
    else:
        dat = None
    return File(content, dat, slug, ext)

Post = namedtuple('Post', 'title date tags pre content location')
def readpost(path):
    pf = parse(path, has_date=True)
    location = os.path.join('post',
            '{:04}'.format(pf.date.year),
            '{:02}'.format(pf.date.month),
            '{:02}'.format(pf.date.day),
            pf.slug + '.html')
    tags = set(pf.content.meta.get('tags', []))
    return Post(' '.join(pf.content.meta['title']), pf.date, tags,
            pf.content.sects['pre'],
            '\n'.join(pf.content.sects.values()), location)

Project = namedtuple('Project', 'name description source ml aur content location')
def readproject(path):
    pf = parse(path)
    source = pf.content.meta.get('source', [None])[0]
    ml = pf.content.meta.get('ml', [None])[0]
    aur = pf.content.meta.get('aur', [None])[0]
    content = '\n'.join(pf.content.sects.values())
    location = os.path.join('project', pf.slug + '.html')
    return Project(' '.join(pf.content.meta['name']),
            pf.content.sects.get('desc', content), source, ml, aur, content,
            location);

def output(dest, cont):
    dest = os.path.join(OUTPUT, dest)
    destdir = os.path.dirname(dest)
    if not os.path.exists(destdir):
        os.makedirs(destdir)
    with open(dest, 'w') as f:
        f.write(cont)

def outputpost(env, post, tags):
    page = {
        'title': post.title,
        'description': md(post.pre),
        'keywords': ', '.join(KWORDS | post.tags),
        'date': post.date,
        'content': md(post.content),
        'tags': sorted(post.tags & set(tags)),
    }
    output(post.location, env.get_template('post.html').render(page=page))

def outputtag(env, posts, tag):
    page = {
        'title': 'Posts tagged - {}'.format(tag),
        'description': "List of posts tagged '{}'.".format(tag),
        'keywords': ', '.join(KWORDS | {tag}),
        'tag': tag,
        'posts': [ p for p in posts if tag in p.tags ],
    }
    output('tag/{}.html'.format(tag), env.get_template('tag.html').render(page=page))

def outputproject(env, project):
    page = {
        'title': project.name,
        'description': project.description.replace('\n', ' '),
        'keywords': ', '.join(KWORDS | {project.name}),
        'content': md(project.content),
        'source': project.source,
        'ml': project.ml,
        'aur': project.aur,
    }
    output(project.location, env.get_template('project.html').render(page=page))

def main(argv=['generate.py']):
    from getopt import getopt
    global OUTPUT

    opts = dict(getopt(argv[1:], "o:b:")[0])
    OUTPUT = opts.get('-o', OUTPUT)
    baseurl = opts.get('-b', 'https://the-tk.com')

    run(['rm', '-rf', os.path.join(OUTPUT, '*')])

    env = Environment(loader=FileSystemLoader('./templates'), autoescape=True)
    env.globals['site'] = {'baseurl': baseurl}
    env.filters['datefmt'] = lambda d, f='%Y-%m-%d': d.strftime(f)
    env.filters['md'] = md

    posts = glob(os.path.join(CONTENT, 'posts', '*'))
    posts = [p for p in posts if not os.path.split(p)[1].startswith('_')]
    posts = sorted(map(readpost, posts), key=attrgetter('date'), reverse=True)
    tags = Counter(chain(*(p.tags for p in posts)))
    tags = sorted(k for k, v in tags.items() if v > 1)

    page = {
        'title': 'Blog',
        'description': 'New posts will appear chronologically on this page.',
        'keywords': ', '.join(KWORDS | set(tags)),
        'tags': tags,
        'posts': posts,
    }
    output('blog.html', env.get_template('blog.html').render(page=page))
    output('blog.atom.xml', env.get_template('blog.atom.xml').render(page=page))

    projects = glob(os.path.join(CONTENT, 'projects', '*'))
    projects = [p for p in projects if not os.path.split(p)[1].startswith('_')]
    projects = sorted(map(readproject, projects), key=lambda e: e.name.lower())

    page = {
        'title': 'Projects',
        'description': 'This is a listing of all of my notable projects.',
        'keywords': ', '.join(KWORDS),
        'projects': projects,
    }
    output('projects.html', env.get_template('projects.html').render(page=page))

    page = {
        'title': 'the-tk.com',
        'description': 'This is my website. Here you can find some blog posts and descriptions for notable projects.',
        'keywords': ', '.join(KWORDS),
        'posts': posts[:3],
    }
    output('index.html', env.get_template('index.html').render(page=page))

    for post in posts:
        outputpost(env, post, tags)
    for tag in tags:
        outputtag(env, posts, tag)
    for project in projects:
        outputproject(env, project)

    for code, error in ERRORS.items():
        page = {
            'title': 'Error: {} - {}'.format(code, error),
            'code': code,
            'error': error,
        }
        output('error/{}.html'.format(code), env.get_template('error.html').render(page=page))

    with open(os.path.join(OUTPUT, 'style.css'), 'w') as f:
        with open(os.path.join(CONTENT, 'style.css')) as css:
            f.write(css.read())
        f.write(HtmlFormatter().get_style_defs('.codehilite'))
    run(['cp', '-r', os.path.join(CONTENT, 'images'), OUTPUT])

if __name__ == '__main__':
    from sys import argv
    main(argv)