# nginx for chess: browsers (web and WASM clients) call <origin>/chess/api/...
# and <origin>/chess/health, which map to the server's /api/... and /health;
# /chess itself redirects to the project page. Replace <server-address> and
# <port>: the FreeBSD jail's address and chessd_port, or 127.0.0.1 and
# CHESSD_PORT for a Linux install on the same host (default port 8080).
#
# chess-server keys rate limits on X-Real-IP, trusted only from the addresses
# in its trusted proxies (chessd_trusted_proxies or CHESSD_TRUSTED_PROXIES):
# the address this nginx connects from, as the server sees it.
# $remote_addr must be the real client: with PROXY protocol in front of nginx,
# set real_ip_header proxy_protocol and set_real_ip_from for that hop.

# --- http {} context ---
upstream chess_api {
    server <server-address>:<port>;
    keepalive 16;
}

# --- TLS server {} context ---
location /chess/api/ {
    proxy_pass http://chess_api/api/;
    proxy_http_version 1.1;
    # Empty Connection header lets nginx reuse upstream keepalive connections.
    proxy_set_header Connection "";
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $remote_addr;
    proxy_set_header X-Forwarded-Proto https;

    # Long-polling holds a request up to 30 seconds.
    proxy_buffering off;
    proxy_read_timeout 60s;
    proxy_send_timeout 60s;

    # API payloads are small JSON documents.
    client_max_body_size 16k;
}

location = /chess/health {
    proxy_pass http://chess_api/health;
    proxy_http_version 1.1;
    proxy_set_header Connection "";
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_read_timeout 10s;
}

# Short link: /chess and /chess/ redirect to the page that embeds the client
# (adjust /projects/chess/). 302 rather than 301: browsers cache a 301
# indefinitely, which would loop if the direction is ever reversed. A server
# listening on a non-default port (PROXY protocol or TLS passthrough behind a
# front end) needs `absolute_redirect off;` so the port does not leak into
# Location. If this server block also answers for other host names, guard with
# a host map so only the main site redirects.
location = /chess {
    return 302 /projects/chess/$is_args$args;
}
location = /chess/ {
    return 302 /projects/chess/$is_args$args;
}

# Everything else under /chess is not served by the API.
location /chess/ {
    return 404;
}