//================================================================
/**
 * @packageDocumentation
 * @module std
 */
//================================================================
import { MultiTreeMap } from "../internal/container/associative/MultiTreeMap";
import { ITreeContainer } from "../internal/container/associative/ITreeContainer";

import { IForwardIterator } from "../iterator/IForwardIterator";
import { MapElementList } from "../internal/container/associative/MapElementList";
import { MultiMapTree } from "../internal/tree/MultiMapTree";
import { Comparator } from "../internal/functional/Comparator";

import { IPair } from "../utility/IPair";
import { Entry } from "../utility/Entry";
import { Temporary } from "../internal/functional/Temporary";

/**
 * Multiple-key Map based on Tree.
 *
 * @author Jeongho Nam - https://github.com/samchon
 */
export class TreeMultiMap<Key, T> extends MultiTreeMap<
    Key,
    T,
    TreeMultiMap<Key, T>,
    TreeMultiMap.Iterator<Key, T>,
    TreeMultiMap.ReverseIterator<Key, T>
> {
    private tree_!: MultiMapTree<Key, T, TreeMultiMap<Key, T>>;

    /* ---------------------------------------------------------
        CONSTURCTORS
    --------------------------------------------------------- */
    /**
     * Default Constructor.
     *
     * @param comp A binary function predicates *x* element would be placed before *y*. When returns `true`, then *x* precedes *y*. Note that, because *equality* is predicated by `!comp(x, y) && !comp(y, x)`, the function must not cover the *equality* like `<=` or `>=`. It must exclude the *equality* like `<` or `>`. Default is {@link less}.
     */
    public constructor(comp?: Comparator<Key>);

    /**
     * Initializer Constructor.
     *
     * @param items Items to assign.
     * @param comp A binary function predicates *x* element would be placed before *y*. When returns `true`, then *x* precedes *y*. Note that, because *equality* is predicated by `!comp(x, y) && !comp(y, x)`, the function must not cover the *equality* like `<=` or `>=`. It must exclude the *equality* like `<` or `>`. Default is {@link less}.
     */
    public constructor(items: IPair<Key, T>[], comp?: Comparator<Key>);

    /**
     * Copy Constructor.
     *
     * @param obj Object to copy.
     */
    public constructor(obj: TreeMultiMap<Key, T>);

    /**
     * Range Constructor.
     *
     * @param first Input iterator of the first position.
     * @param last Input iterator of the last position.
     * @param comp A binary function predicates *x* element would be placed before *y*. When returns `true`, then *x* precedes *y*. Note that, because *equality* is predicated by `!comp(x, y) && !comp(y, x)`, the function must not cover the *equality* like `<=` or `>=`. It must exclude the *equality* like `<` or `>`. Default is {@link less}.
     */
    public constructor(
        first: Readonly<IForwardIterator<IPair<Key, T>>>,
        last: Readonly<IForwardIterator<IPair<Key, T>>>,
        comp?: Comparator<Key>,
    );

    public constructor(...args: any[]) {
        super((thisArg) => new MapElementList(<Temporary>thisArg) as Temporary);

        ITreeContainer.construct<
            Key,
            Entry<Key, T>,
            TreeMultiMap<Key, T>,
            TreeMultiMap.Iterator<Key, T>,
            TreeMultiMap.ReverseIterator<Key, T>,
            IPair<Key, T>
        >(
            this,
            TreeMultiMap,
            (comp) => {
                this.tree_ = new MultiMapTree(
                    this as TreeMultiMap<Key, T>,
                    comp,
                );
            },
            ...args,
        );
    }

    /**
     * @inheritDoc
     */
    public clear(): void {
        super.clear();

        this.tree_.clear();
    }

    /**
     * @inheritDoc
     */
    public swap(obj: TreeMultiMap<Key, T>): void {
        // SWAP CONTENTS
        [this.data_, obj.data_] = [obj.data_, this.data_];
        MapElementList._Swap_associative(
            this.data_ as Temporary,
            obj.data_ as Temporary,
        );

        // SWAP RB-TREE
        MultiMapTree._Swap_source(this.tree_, obj.tree_);
        [this.tree_, obj.tree_] = [obj.tree_, this.tree_];
    }

    /* ---------------------------------------------------------
        ACCESSORS
    --------------------------------------------------------- */
    /**
     * @inheritDoc
     */
    public key_comp(): Comparator<Key> {
        return this.tree_.key_comp();
    }

    /**
     * @inheritDoc
     */
    public lower_bound(key: Key): TreeMultiMap.Iterator<Key, T> {
        return this.tree_.lower_bound(key);
    }

    /**
     * @inheritDoc
     */
    public upper_bound(key: Key): TreeMultiMap.Iterator<Key, T> {
        return this.tree_.upper_bound(key);
    }

    /* ---------------------------------------------------------
        POST-PROCESS
    --------------------------------------------------------- */
    protected _Handle_insert(
        first: TreeMultiMap.Iterator<Key, T>,
        last: TreeMultiMap.Iterator<Key, T>,
    ): void {
        for (; !first.equals(last); first = first.next())
            this.tree_.insert(first);
    }

    protected _Handle_erase(
        first: TreeMultiMap.Iterator<Key, T>,
        last: TreeMultiMap.Iterator<Key, T>,
    ): void {
        for (; !first.equals(last); first = first.next())
            this.tree_.erase(first);
    }
}

/**
 *
 */
export namespace TreeMultiMap {
    // HEAD
    /**
     * Iterator of {@link TreeMultiMap}
     */
    export type Iterator<Key, T> = MapElementList.Iterator<
        Key,
        T,
        false,
        TreeMultiMap<Key, T>
    >;

    /**
     * Iterator of {@link TreeMultiMap}
     */
    export type ReverseIterator<Key, T> = MapElementList.ReverseIterator<
        Key,
        T,
        false,
        TreeMultiMap<Key, T>
    >;

    // BODY
    export const Iterator = MapElementList.Iterator;
    export const ReverseIterator = MapElementList.ReverseIterator;
}