import datetime
import os
import re
from typing import Optional

from markdown import markdown

from flask import Flask, abort, send_from_directory, render_template

basedir = os.path.abspath(os.path.join(os.path.realpath(__file__), '..', '..'))
templates_dir = os.path.join(basedir, 'templates')
static_dir = os.path.join(basedir, 'static')
pages_dir = os.path.join(static_dir, 'pages')
img_dir = os.path.join(static_dir, 'img')
css_dir = os.path.join(static_dir, 'css')

app = Flask(__name__, template_folder=templates_dir)


def parse_page_title(page: str) -> str:
    if page.endswith('.md'):
        page = page[:-3]

    return page.replace('-', ' ')


def get_page_metadata(page: str) -> dict:
    if not page.endswith('.md'):
        page = page + '.md'

    if not os.path.isfile(os.path.join(pages_dir, page)):
        abort(404)

    metadata = {}
    with open(os.path.join(pages_dir, page), 'r') as f:
        for line in f.readlines():
            if not line:
                continue

            if not (m := re.match(r'^\[//]: # \(([^:]+):\s*([^)]+)\)\s*$', line)):
                break

            metadata[m.group(1)] = m.group(2)

    return metadata


def get_page(page: str, title: Optional[str] = None):
    if not page.endswith('.md'):
        page = page + '.md'

    metadata = get_page_metadata(page)
    with open(os.path.join(pages_dir, page), 'r') as f:
        return render_template('article.html',
                               title=title if title else metadata.get('title', 'Platypush Blog'),
                               published=(datetime.date.fromisoformat(metadata['published']).strftime('%b %d, %Y')
                                          if metadata.get('published') else None),
                               content=markdown(f.read(),extensions=['fenced_code', 'codehilite']))


@app.route('/', methods=['GET'])
def home_route():
    return get_page('Home', title='Platypush Blog')


@app.route('/favicon.ico', methods=['GET'])
def favicon_route():
    return send_from_directory(img_dir, 'favicon.ico')


@app.route('/img/<img>', methods=['GET'])
def img_route(img: str):
    return send_from_directory(img_dir, img)


@app.route('/css/<style>', methods=['GET'])
def css_route(style: str):
    return send_from_directory(css_dir, style)


@app.route('/<path:path>', methods=['GET'])
def catch_all(path: str):
    if path.endswith('.md'):
        return get_page(path)

    abort(404)