BadOPCode/NoDash

/**
 * @namespace NoDash
 * @author Shawn Rapp
 * @license MIT
 */
"use strict";

export type TDecision = string | number | undefined;

export interface IDecisionTree {
    [key: string]: any;
}

export const defaultUnknownDecision = (decision: any) => {
    console.error("Unknown \"" + decision + "\" command.");
};

const processOption = (decisionTree: IDecisionTree, decision: TDecision, params?: any) => {
    return (decisionTree[`${decision}`] instanceof Function)
        ? decisionTree[`${decision}`](params)
        : decisionTree[`${decision}`];
};

const processDefaultOption = (decisionTree: IDecisionTree, decision: TDecision, params?: any) => {
    return (decisionTree.default instanceof Function)
        ? decisionTree.default(`${decision}`, params)
        : decisionTree.default;
};

const runDecision = (decisionTree: IDecisionTree, decision: any, params?: any) => {
    if (decisionTree[`${decision}`]) {
        return processOption(decisionTree, decision, params);
    }

    if (decisionTree.default) { // fall back to default if specified
        return processDefaultOption(decisionTree, decision, params);
    }

    // default was not specified
    defaultUnknownDecision(`${decision}`);
};

export const Decision = (decisionTree: IDecisionTree) => {
    return (decision?: any, params?: any) => {
        if (!decision) { // blank decision
            return runDecision(decisionTree, "default");
        }
        return runDecision(decisionTree, decision, params);
    };
};

export default Decision;