# aqserv, a proof of concept server for Aquarius
# Copyright 2020 Hannu Hartikainen. AGPLv3.

import os
import os.path
import socketserver
import urllib.parse

HOST = "0.0.0.0"
PORT = 1970
MAX_PACKET_LENGTH = 508
CWD = os.getcwd()

# monkey-patch aquarius:// support in urljoin :shrug:
urllib.parse.uses_relative.append("aquarius")
urllib.parse.uses_netloc.append("aquarius")

class AquariusHandler(socketserver.BaseRequestHandler):
    def handle(self):
        req, socket = self.request
        url = urllib.parse.urlparse(req.strip())
        if url.scheme != b"aquarius":
            content = b"59 unsupported url\r\n"
        else:
            req_path = url.path.lstrip(b"/").decode("utf-8")
            path = os.path.join(CWD, req_path)
            if os.path.commonpath([CWD, path]) != CWD:
                # avoid escapes like ../
                content = b"59 bad request path\r\n"
            else:
                if os.path.isdir(path):
                    path = os.path.join(path, "index.gemini")
                if os.path.exists(path):
                    content = b"20 text/gemini\r\n"
                    with open(path, 'rb') as f:
                        content += f.read()
                else:
                    content = b"51 not found\r\n"

        packets = [content[i:i+MAX_PACKET_LENGTH]
            for i in range(0, len(content), MAX_PACKET_LENGTH)]
        print(f"{content[0:2].decode('utf-8')} {self.client_address[0]} {req.strip().decode('utf-8')} - {len(packets)} packets")

        for packet in packets:
            socket.sendto(packet, self.client_address)

if __name__ == "__main__":
    with socketserver.UDPServer((HOST, PORT), AquariusHandler) as server:
        server.serve_forever()