import { Variable, type MustacheValue } from "./Variable"
import { hasDuplicates } from "./helperFunctions"

/**
 * A generic class to create a view (the context for a Mustache.render() call). This class's _collection property holds all the names in any subsequently created variable registry via the allKeys getter.
 * @todo Prevent duplicates
 */
export class VariableView {
    private static _collection:VariableView[] = [];

    static get all(): Record<string, MustacheValue> {
        return Object.fromEntries(
            VariableView._collection.flatMap(view => Object.entries(view))
        );
    };
    static get allNames(){
        return VariableView._collection.map(variable=>Object.keys(variable)).flat();
    };    

    [key: string]: MustacheValue;  // [key:string] gives permission for arbitrary string keys

    constructor(...variableValuePairs:Variable[]){
        variableValuePairs.forEach(pair=>{
            this[pair.key] = pair.value;

            if (VariableView.allNames.includes(pair.key)){
                console.warn(`Master variable list already contains the variable ${pair.key} being added by ${this.constructor.name}.`);

                console.trace();
            }
        });

        VariableView._collection.push(this);

        if (hasDuplicates(variableValuePairs.map(pair=>pair.key))){
            console.warn(`Duplicated values in ${this.constructor.name}. (And yes, I should and will add where those occur.)`)
        };
    };

    add(...variableValuePair:Variable[]){
        variableValuePair.forEach(pair=>{
            // It would be a good idea to include a check for duplicate keys
            this[pair.key] = pair.value
        })
    };
    
    replace(variableKey:string,value:string|Function){
        this[variableKey] = value;
    };
};