import http.server
import socketserver
import cgi
from urllib.parse import unquote, parse_qs
import re
import subprocess

PORT = 8000
url_format = re.compile(r"^(?:(?:https://)?platform\.physik\.kit\.edu/codimd/)?(?P<id>[\w_]+)([\?#].*)?$")

class CodiToPdfHandler(http.server.SimpleHTTPRequestHandler):
    def __init__(self, *args, **kwargs):
         super().__init__(*args, directory="/app/html", **kwargs)

    # forward get requests
    def do_GET(self):
        print(self.path)
        print(self.headers)
        super().do_GET()
        return

    def do_POST(self):
        content_length = int(self.headers["Content-Length"])
        _body = self.rfile.read(content_length)
        body = unquote(_body.decode("ASCII"))
        post_data = parse_qs(body)
        pad = post_data["pad"][0]
        pad_id = url_format.match(pad).group("id")

        subprocess.call(["codimd", "export", "--md", pad_id, "tmp.md"])
        subprocess.call(["pandoc", "tmp.md", "-o", "tmp.pdf"])
        pdf = open("tmp.pdf", "rb").read()
        subprocess.call(["rm", "tmp.md", "tmp.pdf"])

        self.send_response(200)
        self.send_header("Content-Type", "application/pdf")
        self.send_header("Content-Length", str(len(pdf)))
        self.end_headers()

        self.wfile.write(pdf)
        return

with http.server.ThreadingHTTPServer(("", PORT), CodiToPdfHandler) as httpd:
    httpd.serve_forever()