//================================================================
/**
 * @packageDocumentation
 * @module std.base
 */
//================================================================
import { IContainer } from "../../base/container/IContainer";

/**
 * Basic reverse iterator.
 *
 * @author Jeongho Nam - https://github.com/samchon
 */
export abstract class ReverseIterator<
    T extends PElem,
    Source extends IContainer<T, Source, Base, This, PElem>,
    Base extends IContainer.Iterator<T, Source, Base, This, PElem>,
    This extends ReverseIterator<T, Source, Base, This, PElem>,
    PElem = T,
> implements IContainer.ReverseIterator<T, Source, Base, This, PElem>
{
    protected base_: Base;

    /* ---------------------------------------------------------
        CONSTRUCTORS
    --------------------------------------------------------- */
    /**
     * Initializer Constructor.
     *
     * @param base The base iterator.
     */
    public constructor(base: Base) {
        this.base_ = base.prev();
    }

    // CREATE A NEW OBJECT WITH SAME (DERIVED) TYPE
    protected abstract _Create_neighbor(base: Base): This;

    /* ---------------------------------------------------------
        ACCESSORS
    --------------------------------------------------------- */
    /**
     * Get source container.
     *
     * @return The source container.
     */
    public source(): Source {
        return this.base_.source();
    }

    /**
     * @inheritDoc
     */
    public base(): Base {
        return this.base_.next();
    }

    /**
     * @inheritDoc
     */
    public get value(): T {
        return this.base_.value;
    }

    /* ---------------------------------------------------------
        MOVERS
    --------------------------------------------------------- */
    /**
     * @inheritDoc
     */
    public prev(): This {
        // this.base().next()
        return this._Create_neighbor(this.base().next());
    }

    /**
     * @inheritDoc
     */
    public next(): This {
        // this.base().prev()
        return this._Create_neighbor(this.base_);
    }

    /* ---------------------------------------------------------
        COMPARES
    --------------------------------------------------------- */
    /**
     * @inheritDoc
     */
    public equals(obj: This): boolean {
        return this.base_.equals(obj.base_);
    }
}