import { Session } from './session';

export class Filter {
    private readonly befores: Array<{ 'before': I_before }> = [];
    private readonly afters: Array<{ 'after': I_after }> = [];
    private readonly globalBefores: Array<{ 'before': I_globalBefore }> = [];

    before(filter: { 'before': I_before }) {
        this.befores.push(filter);
    }

    after(filter: { 'after': I_after }) {
        this.afters.push(filter);
    }

    globalBefore(filter: { 'before': I_globalBefore }) {
        this.globalBefores.push(filter);
    }

    beforeFilter(cmd: number, msg: any, session: Session, cb: (hasError?: boolean) => void) {
        let index = 0;
        const cbFunc = (hasError?: boolean) => {
            if (hasError || index >= this.befores.length) {
                cb(hasError);
                return;
            }
            const filter = this.befores[index];
            index++;
            filter.before(cmd, msg, session, cbFunc);
        };

        cbFunc();
    }

    afterFilter(cmd: number, msg: any, session: Session) {
        let index = 0;
        const cbFunc = () => {
            if (index >= this.afters.length) {
                return;
            }
            const filter = this.afters[index];
            index++;
            filter.after(cmd, msg, session, cbFunc);
        };

        cbFunc();
    }

    globalBeforeFilter(info: { cmd: number; msg: Buffer }, session: Session, cb: (hasError?: boolean) => void) {
        let index = 0;
        const cbFunc = (hasError?: boolean) => {
            if (hasError || index >= this.globalBefores.length) {
                cb(hasError);
                return;
            }
            const filter = this.globalBefores[index];
            index++;
            filter.before(info, session, cbFunc);
        };

        cbFunc();
    }
}

export type I_before = (cmd: number, msg: any, session: Session, cb: (hasError?: boolean) => void) => void

export type I_after = (cmd: number, msg: any, session: Session, cb: () => void) => void

export type I_globalBefore = (info: { cmd: number; msg: Buffer }, session: Session, cb: (hasError?: boolean) => void) => void