#!/usr/bin/env python3
"""Both ends of an upload, for tests/shell/test-upload.sh.

    POST /sign/<name>   mints a URL pointing at this server's /s3/<name>, or
                        fails, per the first line of <dir>/mint-mode
    PUT  /s3/<name>     the signed destination
    PUT  /api/<name>    headquarters' own route, which arena no longer uses

Every request is appended to <dir>/requests as "METHOD path", which is what the
shell test asserts on. /api/ is still served so the test can show that nothing
arrives there, even from a manifest that offers it. The port is written to
<dir>/port once bound, because the test asks for port 0 rather than guessing at
a free one.
"""

import http.server
import json
import pathlib
import sys

SIGN_PREFIX = "/sign/"


class Handler(http.server.BaseHTTPRequestHandler):
    directory = pathlib.Path()

    def log_message(self, *args):
        """Quiet. The test reads the request log, not stderr."""

    def record(self):
        with (self.directory / "requests").open("a") as log:
            log.write(f"{self.command} {self.path}\n")

    def discard_body(self):
        length = int(self.headers.get("Content-Length") or 0)
        while length > 0:
            length -= len(self.rfile.read(min(length, 65536)))

    def do_POST(self):
        self.discard_body()
        self.record()
        mode = (self.directory / "mint-mode").read_text().strip()
        if mode != "ok" or not self.path.startswith(SIGN_PREFIX):
            self.send_response(500)
            self.end_headers()
            return
        name = self.path[len(SIGN_PREFIX) :]
        body = json.dumps(
            {
                "url": f"http://{self.headers['Host']}/s3/{name}",
                "method": "PUT",
                "expiresIn": 900,
            }
        ).encode()
        self.send_response(200)
        self.send_header("Content-Type", "application/json")
        self.send_header("Content-Length", str(len(body)))
        self.end_headers()
        self.wfile.write(body)

    def do_PUT(self):
        self.discard_body()
        self.record()
        self.send_response(200)
        self.end_headers()


def main():
    directory = pathlib.Path(sys.argv[1])
    Handler.directory = directory
    server = http.server.ThreadingHTTPServer(("127.0.0.1", 0), Handler)
    (directory / "port").write_text(str(server.server_address[1]))
    server.serve_forever()


if __name__ == "__main__":
    main()