mudb/src/schema/boolean.ts

Real-time database for multiplayer games

import { MuReadStream, MuWriteStream } from '../stream';
import { MuSchema } from './schema';

export class MuBoolean implements MuSchema<boolean> {
    public readonly muType = 'boolean';
    public readonly identity:boolean;
    public readonly json:object;

    constructor (identity?:boolean) {
        this.identity = !!identity;
        this.json = {
            type: 'boolean',
            identity: this.identity,
        };
    }

    public alloc () : boolean { return this.identity; }

    public free (bool:boolean) : void { }

    public equal (a:boolean, b:boolean) : boolean { return a === b; }

    public clone (bool:boolean) : boolean { return bool; }

    public assign (dst:boolean, src:boolean) : boolean { return src; }

    public diff (base:boolean, target:boolean, out:MuWriteStream) : boolean {
        if (base !== target) {
            out.grow(1);
            out.writeUint8(target ? 1 : 0);
            return true;
        }
        return false;
    }

    public patch (base:boolean, inp:MuReadStream) : boolean {
        const result = inp.readUint8();
        if (result > 1) {
            throw new Error(`invalid value for boolean`);
        }
        return !!result;
    }

    public toJSON (bool:boolean) : boolean { return bool; }

    public fromJSON (x:boolean) : boolean {
        if (typeof x === 'boolean') {
            return x;
        }
        return this.identity;
    }
}