import { $joinedUser, $says, $user, asJoin, asSays, asUserInfo, fromNickClaim, fromSays, NickClaim, Says, UserId } from "./gen/secure-chat-protocol.js";
import { during, observe } from "./dataspace.js";
import { Assertion, Ref, Turn } from "./actor.js";
import readline from 'readline';

export default function (t: Turn, ds: Ref) {
    observe(t, ds, $joinedUser, {
        assert(t, j0) {
            const j = asJoin(j0);
            runSession(t, j.uid, j.handle);
        }
    });
}

function runSession(t: Turn, uid: UserId, session: Ref) {
    let username: string | undefined;

    function updateUsername(t: Turn, name: string) {
        const q = t.assert(session, fromNickClaim(NickClaim({ uid, name, k: t.ref({
            message(t, reply0) {
                if (reply0 === true) {
                    username = name;
                    console.log(`Nick changed to ${username}`);
                } else {
                    console.log(`Nick conflict: name is still ${username ?? '<not set>'}`);
                }
                t.retract(q);
            }
        })})));
    }
    updateUsername(t, 'user' + process.pid);

    const users = new Map<UserId, string>();
    observe(t, session, $user, during((_t, ui0) => {
        const ui = asUserInfo(ui0);
        const oldName = users.get(ui.uid);
        console.log(oldName === void 0
            ? `${ui.name} arrived`
            : `${oldName} changed name to ${ui.name}`);
        users.set(ui.uid, ui.name);
        return (_t) => {
            if (users.get(ui.uid) === ui.name) {
                console.log(`${ui.name} departed`);
            }
        };
    }));

    observe(t, session, $says, {
        message(_t: Turn, u0: Assertion): void {
            const u = asSays(u0);
            console.log(`${users.get(u.who) ?? `<unknown ${u.who}>`}: ${u.what}`);
        },
    });

    const rl = readline.createInterface({ input: process.stdin, output: process.stdout });

    rl.on('line', (line: string) => t.freshen(t => {
        if (line.toLowerCase().startsWith('/nick ')) {
            updateUsername(t, line.slice(5).trimLeft());
        } else {
            t.message(session, fromSays(Says({ who: uid, what: line })));
        }
    }));

    rl.on('close', () => t.freshen(t => t.stopActor()));
}