seyfert/vendor/gateway/shard/handleClose.ts

import { GatewayCloseEventCodes } from "../../types/shared.ts";
import { Shard, ShardSocketCloseCodes, ShardState } from "./types.ts";

export async function handleClose(shard: Shard, close: CloseEvent): Promise<void> {
    //   gateway.debug("GW CLOSED", { shardId, payload: event });

    shard.stopHeartbeating();

    switch (close.code) {
        case ShardSocketCloseCodes.TestingFinished: {
            shard.state = ShardState.Offline;
            shard.events.disconnected?.(shard);

            return;
        }
        // On these codes a manual start will be done.
        case ShardSocketCloseCodes.Shutdown:
        case ShardSocketCloseCodes.ReIdentifying:
        case ShardSocketCloseCodes.Resharded:
        case ShardSocketCloseCodes.ResumeClosingOldConnection:
        case ShardSocketCloseCodes.ZombiedConnection: {
            shard.state = ShardState.Disconnected;
            shard.events.disconnected?.(shard);

            // gateway.debug("GW CLOSED_RECONNECT", { shardId, payload: event });
            return;
        }
        // Gateway connection closes which require a new identify.
        case GatewayCloseEventCodes.UnknownOpcode:
        case GatewayCloseEventCodes.NotAuthenticated:
        case GatewayCloseEventCodes.InvalidSeq:
        case GatewayCloseEventCodes.RateLimited:
        case GatewayCloseEventCodes.SessionTimedOut: {
            shard.state = ShardState.Identifying;
            shard.events.disconnected?.(shard);

            return await shard.identify();
        }
        // When these codes are received something went really wrong.
        // On those we cannot start a reconnect attempt.
        case GatewayCloseEventCodes.AuthenticationFailed:
        case GatewayCloseEventCodes.InvalidShard:
        case GatewayCloseEventCodes.ShardingRequired:
        case GatewayCloseEventCodes.InvalidApiVersion:
        case GatewayCloseEventCodes.InvalidIntents:
        case GatewayCloseEventCodes.DisallowedIntents: {
            shard.state = ShardState.Offline;
            shard.events.disconnected?.(shard);

            throw new Error(close.reason || "Discord gave no reason! GG! You broke Discord!");
        }
        // Gateway connection closes on which a resume is allowed.
        case GatewayCloseEventCodes.UnknownError:
        case GatewayCloseEventCodes.DecodeError:
        case GatewayCloseEventCodes.AlreadyAuthenticated:
        default: {
            shard.state = ShardState.Resuming;
            shard.events.disconnected?.(shard);

            return await shard.resume();
        }
    }
}