const { compare }= require('natural-orderby');
const errors = require("./errors.js");
import { SortingFields } from "./freeDatas2HTMLInterfaces";
import { FreeDatas2HTML } from "./freeDatas2HTML";

export class SortingField implements SortingFields
{
    _converter: FreeDatas2HTML;
    _fieldsDOMSelector: string; 
    _datasFieldNb: number;
    _order: "asc"|"desc"|undefined = undefined;

    // Injection de la classe principale, mais uniquement si le nom des champs ont été importés et affichés correctement
    constructor(converter: FreeDatas2HTML, datasFieldNb: number, fieldsDOMSelector: string = "th")
    {
        if(converter.fields === undefined)
            throw new Error(errors.sortingFieldNeedDatas);
        else if(! converter.checkFieldExist(Number(datasFieldNb)))
            throw new Error(errors.sortingFieldFieldNotFound);
        else
        {
            const  fields=document.querySelectorAll(fieldsDOMSelector);
            if(fields === undefined)
                throw new Error(errors.sortingFieldsNotInHTML);
            else if(fields.length !== converter.fields.length)
                throw new Error(errors.sortingFieldsNbFail);
            else
            {
                this._converter=converter;
                this._datasFieldNb=datasFieldNb;
                this._fieldsDOMSelector= fieldsDOMSelector;
            }
        }
    }

    get fieldsDOMSelector() : string
    {
        return this._fieldsDOMSelector;
    }
    
    get datasFieldNb() : number
    {
        return this._datasFieldNb;
    }
    
    get order() : "asc"|"desc"|undefined
    {
        return this._order;
    }
    
    // Création du lien dans le HTML correspondant au champ de classement
    public field2HTML() : void
    {
        if(this._converter === undefined || this._fieldsDOMSelector === "" || this._datasFieldNb === undefined)
            throw new Error(errors.sortingField2HTMLFail);
        else
        {
            const  fields=document.querySelectorAll(this._fieldsDOMSelector);
            let htmlContent=fields[this._datasFieldNb].innerHTML;
            htmlContent="<a href='#freeDatas2HTMLSorting"+this._datasFieldNb+"' id='freeDatas2HTMLSorting"+this._datasFieldNb+"'>"+htmlContent+"</a>";
            fields[this._datasFieldNb].innerHTML=htmlContent;
            const sortingElement=document.getElementById("freeDatas2HTMLSorting"+this._datasFieldNb), field=this;
            sortingElement!.addEventListener("click", function(e) // je sais que sortingElement existe, car je viens de le créer !
            {
                e.preventDefault();
                let order=field._order ;
                if(order === undefined || order === "desc")
                    field._order="asc";
                else
                    field._order="desc";
                field._converter.datasSortedField = field;
                field._converter.refreshView();
            });
        }
    }
    
}