#!/usr/bin/env python3
import os
import re
import sys
import yaml

from jinja2 import Environment, FileSystemLoader
from commonmark import commonmark

# "template macros"
template_replace = [
    ("<notes>", '<aside class="notes">\n'),
    ("</notes>", "\n</aside>"),
]

directory = os.path.dirname(sys.argv[1])

template_env = Environment(
    loader=FileSystemLoader(os.path.join(directory, "../_templates"))
)

if not os.path.isfile(os.path.join(directory, "index.md")):
    raise Exception("{directory} is missing index.md")

files = ["index.md"]
files.extend(
    sorted(
        [
            file
            for file in os.listdir(directory)
            if os.path.isfile(os.path.join(directory, file))
            and re.match(".*\.md$", file)
            and file != "index.md"
        ]
    )
)

config = {
    "theme": "../_assets/reveal.js/css/theme/black.css",
    "mathjax": False,
    "controls": True,
    "progress": True,
    "history": True,
    "center": True,
    "show_notes": False,  # on print
    "width": 1280,
    "height": 800,
    "transition": "none",  # none, fade, slide, convex, concave, zoom
    "background_transition": "none",
}
content = ""

for idx, file in enumerate(files):
    with open(os.path.join(directory, file), "r") as f:
        parts = f.read().split("---\n")

    if idx == 0:
        config = {**config, **yaml.safe_load(parts[0])}
        parts = parts[1:]

    section_content = "<section>"

    for slide in parts:
        for r in template_replace:
            slide = slide.replace(r[0], r[1])

        # parse config
        slide_config = slide.split("\n")[0]
        slide = "\n".join(slide.split("\n")[1:])
        if slide_config != "":
            slide_config = re.split(' (?=(?:[^"]|"[^"]*")*$)', slide_config)
            slide_config = list(
                map(
                    lambda x: x if re.match("^style=.*", x) else f"data-{x}",
                    slide_config,
                )
            )  # data-
            slide_config = " " + " ".join(slide_config)

        slide_content = f"<section{slide_config}>"
        slide_content += commonmark(slide)
        slide_content += "</section>"

        if slide_content != "<section></section>":
            section_content += slide_content

    section_content += "</section>"

    if section_content != "<section></section>":
        content += section_content

with open(os.path.join(directory, "index.html"), "w") as f:
    f.write(template_env.get_template("index.html.j2").render(config, content=content))