# Load environment variables
map "" $webdav_backend {
    default "$WEBDAV_BACKEND";
}

server {
    listen       ${APP_PORT};
    server_name  localhost;

    # serve super-productivity as static files at the path /
    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm;
        try_files $uri $uri/ /index.html;
    }

    # forward requests starting with "/webdav/" to $WEBDAV_BACKEND
    # note: the prefix "/webdav" is removed during forwarding
    location = /webdav {
        return 302 /webdav/;
    }
    location /webdav/ {
        if ($webdav_backend = "") {
            return 404;
        }

        resolver 127.0.0.11;  # resolve webdav_backend by docker internal DNS
        rewrite ^/webdav/(.*)$ /$1 break;   # remove the `/webdav/` prefix
        proxy_pass $webdav_backend;
    }

    # redirect server error pages to the static page /50x.html
    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/share/nginx/html;
    }
}