#!/usr/bin/env python3
"""Serve VT1200 font files over TFTP.

The terminal's "TFTP Font Path" is ``<host>:<filename>``; it requests that exact
filename over TFTP and (if it parses) loads it as a font.  This serves several
plausible names so we catch whatever it asks for.

    sudo python3 -u harness/serve.py [host] [port]
"""
import os
import sys
import time

HERE = os.path.dirname(os.path.abspath(__file__))
ROOT = os.path.dirname(HERE)
sys.path.insert(0, os.path.join(ROOT, "tools"))

import fontgen

FONTS = os.path.join(ROOT, "reference", "fonts")


def load(name):
    with open(os.path.join(FONTS, name), "rb") as fh:
        return fh.read()


def main():
    baseline = load("baseline.pcf")
    evil = load("evil-real.pcf")
    probe = load("probe-uniq.pcf")
    probe_snf = load("probe.snf")
    probe_dec = load("probe-dec.snf")
    probe_dec2 = load("probe-dec2.snf")
    real = load("system-10x20.pcf")
    fonts_dir = load("fonts.dir")
    files = {}
    # The font path value is <host>:<fontdir>.  The terminal fetches
    # "<fontdir>/fonts.dir" (the directory index), then the font files it names.
    for d in ("69", "font", "fonts", "misc", "X11"):
        files[f"{d}/fonts.dir"] = fonts_dir
        files[f"{d}/baseline.pcf"] = baseline
        files[f"{d}/v1200a.pcf"] = baseline
        files[f"{d}/evil.pcf"] = evil
    # also serve the plain names, in case it asks for those first
    for n in ("69", "fonts.dir", "font", "fonts", "ROM", "rom", "real.pcf"):
        files[n] = real
    files["baseline.pcf"] = baseline
    files["evil.pcf"] = evil
    if os.path.exists(os.path.join(FONTS, "fonts.dir")):
        files["fonts.dir"] = load("fonts.dir")

    host = sys.argv[1] if len(sys.argv) > 1 else "100.103.255.254"
    port = int(sys.argv[2]) if len(sys.argv) > 2 else 69
    def resolve(name):
        # The terminal first fetches the bare path, then "<dir>/fonts.dir".
        # Accept ANY name: the index for fonts.dir, the payload otherwise.
        if name == "fonts.dir" or name.endswith("/fonts.dir"):
            return fonts_dir
        if name.endswith(".snf"):
            if "dec2" in name:
                return probe_dec2
            return probe_dec if "dec" in name else probe_snf
        if name.endswith((".pcf", ".DECW$FONT")):
            if "evil" in name:
                return evil
            if "probe" in name:
                return probe
            return baseline
        return baseline          # bare directory name: give it data, not an error

    srv = fontgen.TFTPServer((host, port), files, timeout=60.0, retries=10,
                             resolver=resolve).start()
    print(f"serving {len(files)} names on {srv.address}", flush=True)
    print("  names: " + ", ".join(sorted(files)), flush=True)
    try:
        while True:
            time.sleep(0.5)
            while srv.log:
                ts, name, addr = srv.log.pop(0)
                stamp = time.strftime("%H:%M:%S", time.localtime(ts))
                print(f"{stamp}  {addr[0]}:{addr[1]} requested {name!r}", flush=True)
    except KeyboardInterrupt:
        pass
    finally:
        srv.stop()


if __name__ == "__main__":
    main()