resolve-page-data

resolve-page-data.js

"use strict";

const falze = require( "falze" );
const falzy = require( "falzy" );

const resolvePageData = function resolvePageData( pageData ){
	/*;
		@note:
			pageData if string denotes pageIndex
		@end-note
	*/
	if(
			typeof pageData == "string"
		&&	pageData.length > 0

		&&	( /^\d+$/ ).test( pageData )
	){
		pageData = parseInt( pageData );
	}

	/*;
		@note:
			pageData if number denotes pageIndex
		@end-note
	*/
	if(
		typeof pageData == "number"
	){
		const pageIndex = (
				pageData
			||	1
		);

		pageData = {
			"pageIndex": pageIndex,

			"listCount": 0,

			"pageSize": 0,
			"pageCount": 0,
			"lastPageSize": 0,

			"startIndex": 0,
			"endIndex": 0,

			"currentPageSize": 0
		};
	}

	if(
		falze( pageData )
	){
		pageData = (
			{
				"pageIndex": 1,

				"listCount": 0,

				"pageSize": 0,
				"pageCount": 0,
				"lastPageSize": 0,

				"startIndex": 0,
				"endIndex": 0,

				"currentPageSize": 0
			}
		);
	}

	const pageDataPropertyList = Object.keys( pageData );
	const pageDataPropertyListLength = pageDataPropertyList.length;

	let pageDataProperty = undefined;
	for(
		let pageDataPropertyIndex = 0;
		pageDataPropertyIndex < pageDataPropertyListLength;
		pageDataPropertyIndex++
	){
		pageDataProperty = pageDataPropertyList[ pageDataPropertyIndex ];

		if(
				typeof pageData[ pageDataProperty ] != "number"

			&&	typeof pageData[ pageDataProperty ] == "string"
			&&	( /^\d+$/ ).test( pageData[ pageDataProperty ] )
		){
			pageData[ pageDataProperty ] = parseInt( pageData[ pageDataProperty ] );
		}

		if(
			isNaN( pageData[ pageDataProperty ] ) === true
		){
			const pageDataPropertyValueError = (
				new Error( "invalid page data property value" )
			);

			throw	pageDataPropertyValueError;
		}
	}

	/*;
		@note:
			pageIndex should always default to 1
			and must not be less than 1
		@end-note
	*/
	if(
			falzy( pageData.pageIndex )

		||	pageData.pageIndex <= 0
	){
		pageData.pageIndex = 1;
	}

	if(
			falzy( pageData.listCount )

		||	pageData.listCount < 0
	){
		pageData.listCount = 0;
	}

	if(
			falzy( pageData.pageSize )

		||	pageData.pageSize < 0
	){
		pageData.pageSize = 0;
	}

	if(
			falzy( pageData.pageCount )

		||	pageData.pageCount < 0
	){
		pageData.pageCount = 0;
	}

	if(
			falzy( pageData.lastPageSize )

		||	pageData.lastPageSize < 0
	){
		pageData.lastPageSize = 0;
	}

	if(
			falzy( pageData.startIndex )

		||	pageData.startIndex < 0
	){
		pageData.startIndex = 0;
	}

	if(
			falzy( pageData.endIndex )

		||	pageData.endIndex < 0
	){
		pageData.endIndex = 0;
	}

	pageData.currentPageSize = (
			pageData.endIndex
		-	pageData.startIndex
	);

	return	pageData;
};

module.exports = resolvePageData;