Apps Script - compare strings in two arrays - arrays

Question

I am a stuck on this piece of code. I have an Example sheet with two tabs. The first tab is new items. A new item is comprised of two pieces, a attribute code (string), and an item ID (number). In the other tab "Locations" there are a bunch of empty locations. Each location has primary attribute (string), and a set of secondary attribute codes in a longer string.
I have assigned these two ranges to two unique arrays.
function matchcodes() {
var locss = SpreadsheetApp.getActiveSpreadsheet().getSheetByName('Locations');
var lastlocRow = locss.getLastRow();
var newitems = SpreadsheetApp.getActiveSpreadsheet().getSheetByName('New Items');
var lastNIRow = newitems.getLastRow();
var itemcodes = newitems.getRange("A1:B" + lastNIRow).getValues();
var locations = locationssheet.getRange("A2:D" + lastlocationRow).getValues();
Logger.log(itemcodes)
Logger.log(locations)}
What I am attempting to do is compare itemcodes[i][0] to locations[j][2] (match item attribute with location primary attribute). If the strings match I want to copy itemcodes[i][1] (ItemID) and set it as the value of locations[j][1]. If the strings do not match check the next iteration of locations[j][2].
If no matching attributes are found in locations[j][2], I would like to see if it is contained as a substring in locations[j][3] (starting back at the top and iterating through the whole list of secondary attributes. If the substring code is contained in loactions[j][3] I would like take the same action in the first IF condition.
Once a new item is matched, the loop can break, and the next item can be located itemcodes[i+1][0]. If no match is found in the primary or secondary search, also iterate to the next new item.
Where I'm struggling is writing the condition statements to compare both strings and substrings within strings.
//for (var i = 0; i < itemcodes.length; i++) {
//for (var j = 0; j < locations.length; j++) {
//if (itemcodes[i][0] == locations[j][2]) {
// I want set the value of locations[j][1] with itemcodes[i][1]
}
// if no match is found in entire [j][2] column, search for substring in locations[j][3] column
//if item match is found, or no match is found in all of [j][2] or [j][3] break loop and iterate to [i+1][0] and start the next loop
Input (3 iterations)
Results
Any help would be much appreciated. Or if you can point me to a similar thread. (I've not had any success finding a similar example) Thanks in advance!

Answer 1

Try:
function matchCodes() {
const newItems = SpreadsheetApp.getActiveSpreadsheet().getSheetByName(`New Items`)
const locations = SpreadsheetApp.getActiveSpreadsheet().getSheetByName(`Locations`)
const newItemsValues = newItems.getDataRange().getValues()
const locationsValues = locations.getDataRange().offset(1, 0).getValues()
newItemsValues.forEach(([attribute, id]) => {
const primaryTarget = locationsValues.findIndex(row => row[2] === attribute && row[1] === ``)
if (primaryTarget !== -1) return locationsValues[primaryTarget][1] = id
const secondaryTarget = locationsValues.findIndex(row => row[3].includes(attribute) && row[1] === ``)
if (secondaryTarget !== -1) return locationsValues[secondaryTarget][1] = id
})
locations.getDataRange().offset(1, 0).setValues(locationsValues)
}
Learn More:
Array.findIndex()
Destructuring Assignment