calories.js

const calorieMap = {};

function calculateCalories() {
  let spreadsheet = SpreadsheetApp.getActiveSpreadsheet();

  let calorieSheet = spreadsheet.getSheetByName("Calories");
  let calorieValues = calorieSheet.getRange("A2:B").getDisplayValues();
  for (let [index, item] of calorieValues.entries()) {
    if (item[0].length && item[1].length) {
      calorieMap[item[0].trim()] = parseFloat(item[1].trim());
    } else {
      break;
    }
  }
  let sheet = spreadsheet.getSheetByName("Calorie Tracker");
  let data = sheet.getRange("B2:B").getDisplayValues();
  let outputRange = sheet.getRange("C2:C");
  let outputValues = [];
  for (let [index, value] of data.entries()) {
    if (!value || !value[0].length) {
      outputValues.push([[]]);
      continue;
    }
    let foods = value[0].split(",");
    let calories = 0;
    for (let [idx, food] of foods.entries()) {
      let [foodName, consumed] = food.split("-");
      if (calorieMap[foodName]) {
        calories += calorieMap[foodName] * parseFloat(consumed);
      }
    }
    outputValues.push([calories]);
  }
  outputRange.setValues(outputValues);
}