#!/usr/bin/env python3

import sys
import re
from markdown import markdown
from strictyaml import load as load_yaml
from pymaybe import maybe as maybe
from functools import partial as p
from ipo import read, write, dictmap, starstarmap, ipo, all_before, all_after


LIST_ITEM_TEMPLATE = """
				<li><a href="{path}">
					<div class="title">{title}</div>
					<div class="summary">{summary}</div>
				</a></li>"""


def blog_page_template():
	with open("templates/blog.html") as fh:
		return fh.read()


def date_from_filename(filename):
	return maybe(
		re.search(r"(?:^|/)([0-9]{4}-[0-9]{2}-[0-9]{2})[^/]+$", filename)
	).group(1).or_none()


def blog_page_metadata(filename):
	with open(filename) as file:
		metadata_from_file = (
			read(file=file) | p(all_before, p(re.fullmatch, "---+")) | "\n".join |
			load_yaml | (lambda x: x.data)
		).data

	return {
		**metadata_from_file,
		"path": re.sub(r".md$", "", filename),
		"published": date_from_filename(filename)
	}


def blog_page_body(filename):
	with open(filename) as file:
		return (
			read(file=file) | p(all_after, p(re.fullmatch, "---+")) | "\n".join |
			p(markdown, extensions=["abbr", "toc", "smarty", "fenced_code", "codehilite"])
		).data


def safe_metadata(metadata):
	return {
		k: (
			v
			if k in ("published", "path")
			else markdown(v, extensions=["smarty"]).replace("<p>", "").replace("</p>", "")
		)
		for k, v in metadata.items()
	}


def main():
	if sys.argv[1] == "--index":
		blog_post_list = (
			ipo(sys.argv[4:]) |
			p(map, blog_page_metadata) |
			p(sorted, key=lambda x: x["published"]) |
			p(map, safe_metadata) |
			p(map, lambda metadata: LIST_ITEM_TEMPLATE.format(**metadata)) |
			"".join
		)

		with open(sys.argv[2]) as file_in, open(sys.argv[3], "w") as file_out:
			print(
				file_in.read().format(blog_posts=blog_post_list),
				end="", file=file_out
			)

	else:
		metadata = safe_metadata(blog_page_metadata(sys.argv[1]))
		body = blog_page_body(sys.argv[1])

		with open(sys.argv[2], "w") as file_out:
			print(
				blog_page_template().format(**metadata, body=body),
				end="", file=file_out
			)

if __name__ == '__main__':
	main()