Final Project - Handler Class

StockItemHandler.apxc

//A Utility class to process Stock Item records from the Stock Item Handler
public with sharing class StockItemHandler {
	
	//Default Constructor
	public StockItemHandler() {
		
	}

	//Create methods here to handle the before insert, before delete and utility processes described in the requirements
	//They should accept lists of Stock_Item__c records from the trigger
	public static void onBeforeInsert(List<Stock_Item__c> newStockItems) {

        //Before a Stock Item can be created, check that there is not already a stock item record with a matching name. 
        //If there is already a Stock Item with that name, change the name so that it is the name entered, 
        //plus the words “Duplicate Item”.  We have a process in place to check for these elsewhere.
        //
        //first create a list of all existing Item Names in the Org.
        List<Stock_Item__c> allStockItems =  new List<Stock_Item__c>([SELECT Item_Name__c FROM Stock_Item__c]);
        
        //loop through the Items we are trying to create and
        for (Stock_Item__c newItem : newStockItems){
            
            //loop through existing
  		    for (Stock_Item__c item : allStockItems) {
                //compare new and existing name to check if each new Item Name matches any from the existing list
                if (newItem.Item_Name__c == item.Item_Name__c) {
                	/******option 1 with renaming:
                    //if yes, append "duplicate item" to the name
                    newItem.Item_Name__c = item.Item_Name__c + ': Duplicate Item';
					*/
                	/******option 2 with exception*/
                    newItem.addError('Duplicate name found! Fix & resubmit.', true);
                } 
                
                

            }
        //No DML needed here, since it's a BEFORE insert trigger
        //}
        } 
	}    
    public static void onBeforeDelete(List<Stock_Item__c> deleteStockItems, Map<Id, Stock_Item__c> deletedStockItemsMap) {

        //Before a Stock Item is deleted, make sure that the stock on hand is at 0.  
        //If it is not, Create a case so that someone is alerted. 
        //The case should indicate the name of the item that was deleted, the id, 
        //and the number of stock that were on hand when it was deleted in the description.  
        //The rest of the case can be configured however you think best.
        
        //make a list to hold Cases for bulkifying
        List<Case> createCases = new List<Case>();
        
        //make a list of items to delete - or use the List<Stock_Item__c> deleteStockItems
        //loop through the list and check stock levels
        for(Stock_Item__c Item : deleteStockItems){
            if(Item.Stock_on_Hand__c > 0) {
                //create a Case
                System.debug(Item.Item_Name__c + ' has stock on hand');
                Case cse = new Case();
                cse.Status = 'New';
                cse.Origin = 'Internal';
                cse.Subject = 'Clean up stock for "' + Item.Item_Name__c + '" (' + Item.Id + ')';
                cse.Description = 'Stock item "'+Item.Item_Name__c+'" was deleted but it has '+Item.Stock_on_Hand__c+' in stock.';
                createCases.add(cse);
            }  
        }
        insert createCases;

    }
    
    public static List<Stock_Item__c> getLowStockItems(){
        /*
        We need a method that can be called from elsewhere in our codebase called getLowStockItems
		This should return a list of all the Stock Items that have a stock on hand count 
		at or below their minimum stock level.
		It should include the following fields for the Stock Items it returns:
			ID
			Item_Name__c
			Item_Stock_is_Low__c
			Minimum_Stock_Level__c
			Stock_on_Hand__c
		*/
        //make a list of all stock items that meet the criteria
        List<Stock_Item__c> lowStockItems = new List<Stock_Item__c>(
            [SELECT Id, Item_Name__c, Item_Stock_is_Low__c, Minimum_Stock_Level__c, Stock_on_Hand__c
            FROM Stock_Item__c
            WHERE Item_Stock_is_Low__c = TRUE] 
        );
        //if anything is found, output details to debug log
        if(lowStockItems.size() > 0){
       		System.debug('Found '+lowStockItems.size()+' items with low inventory:');
        //Loop through the low stock items list and output to debug log
        	for(Stock_Item__c item :lowStockItems){
            	System.debug(item.Item_Name__c+', ID:'+item.Id+', Min: '+item.Minimum_Stock_Level__c+', Inv: '+item.Stock_on_Hand__c);
        	}
        } else 
            System.debug('Inventory levels are okay!');
        return lowStockItems;
    }
	
}