/**
 * A bidirectional map written in TypeScript.
 *
 * @author Trevor Sears <trevorsears.main@gmail.com>
 * @version v1.0.0
 * @since v0.1.0
 */
export class BiMap<K = any, V = any> {
	public primaryMap: Map<K, V>;
	public secondaryMap: Map<V, K>;
	
	public constructor() {
		this.primaryMap = new Map<K, V>();
		this.secondaryMap = new Map<V, K>();
	}

	public getValues(): IterableIterator<V> {
		return this.primaryMap.values();
	}
	
	public get(key: K): V | undefined {
		return this.getFromKey(key);
	}
	
	public set(key: K, value: V): void {
		this.setFromKey(key, value);
	}
	
	public getFromKey(key: K): V | undefined {
		return this.primaryMap.get(key);
	}
	
	public getFromValue(value: V): K | undefined {
		return this.secondaryMap.get(value);
	}
	
	public setFromKey(key: K, value: V): void {
		this.primaryMap.set(key, value);
		this.secondaryMap.set(value, key);
	}
	
	public setFromValue(value: V, key: K): void {
		this.setFromKey(key, value);
	}
	
	public removeByKey(key: K): V | undefined {
		if (this.primaryMap.has(key)) {
			const value: V = this.primaryMap.get(key) as V;
			this.primaryMap.delete(key);
			this.secondaryMap.delete(value);
			return value;
		} else return undefined;
	}
	
	public removeByValue(value: V): K | undefined {
		if (this.secondaryMap.has(value)) {
			const key: K = this.secondaryMap.get(value) as K;
			this.primaryMap.delete(key);
			this.secondaryMap.delete(value);
			return key;
		} else return undefined;
	}
	
	public hasKey(key: K): boolean {
		return this.primaryMap.has(key);
	}
	
	public hasValue(value: V): boolean {
		return this.secondaryMap.has(value);
	}
	
	public clear(): void {
		this.primaryMap.clear();
		this.secondaryMap.clear();
	}

	public size(): number {
		return this.primaryMap.size;
	}
}