esx_core-esx-framework/server/main.lua

ESX             = nil
local ShopItems = {}

TriggerEvent('esx:getSharedObject', function(obj) ESX = obj end)

-- Load items
MySQL.ready(function()
	local itemResult = MySQL.Sync.fetchAll('SELECT * FROM items')
	local shopResult = MySQL.Sync.fetchAll('SELECT * FROM shops')

	local itemInformation = {}
	for i=1, #itemResult, 1 do

		if itemInformation[itemResult[i].name] == nil then
			itemInformation[itemResult[i].name] = {}
		end

		itemInformation[itemResult[i].name].label = itemResult[i].label
		itemInformation[itemResult[i].name].limit = itemResult[i].limit
	end

	for i=1, #shopResult, 1 do
		if itemInformation[shopResult[i].item] then
			if ShopItems[shopResult[i].store] == nil then
				ShopItems[shopResult[i].store] = {}
			end

			if itemInformation[shopResult[i].item].limit == -1 then
				itemInformation[shopResult[i].item].limit = 30
			end

			table.insert(ShopItems[shopResult[i].store], {
				label = itemInformation[shopResult[i].item].label,
				item  = shopResult[i].item,
				price = shopResult[i].price,
				limit = itemInformation[shopResult[i].item].limit
			})
		else
			print(('esx_shops: invalid item "%s" found!'):format(shopResult[i].item))
		end
	end
end)

ESX.RegisterServerCallback('esx_shops:requestDBItems', function(source, cb)
	cb(ShopItems)
end)

RegisterServerEvent('esx_shops:buyItem')
AddEventHandler('esx_shops:buyItem', function(itemName, amount, zone)
	local _source = source
	local xPlayer = ESX.GetPlayerFromId(_source)
	local sourceItem = xPlayer.getInventoryItem(itemName)

	amount = ESX.Math.Round(amount)

	-- is the player trying to exploit?
	if amount < 0 then
		print('esx_shops: ' .. xPlayer.identifier .. ' attempted to exploit the shop!')
		return
	end

	-- get price
	local price = 0
	local itemLabel = ''

	for i=1, #ShopItems[zone], 1 do
		if ShopItems[zone][i].item == itemName then
			price = ShopItems[zone][i].price
			itemLabel = ShopItems[zone][i].label
			break
		end
	end

	price = price * amount

	-- can the player afford this item?
	if xPlayer.getMoney() >= price then
		-- can the player carry the said amount of x item?
		if sourceItem.limit ~= -1 and (sourceItem.count + amount) > sourceItem.limit then
			TriggerClientEvent('esx:showNotification', _source, _U('player_cannot_hold'))
		else
			xPlayer.removeMoney(price)
			xPlayer.addInventoryItem(itemName, amount)
			TriggerClientEvent('esx:showNotification', _source, _U('bought', amount, itemLabel, ESX.Math.GroupDigits(price)))
		end
	else
		local missingMoney = price - xPlayer.getMoney()
		TriggerClientEvent('esx:showNotification', _source, _U('not_enough', ESX.Math.GroupDigits(missingMoney)))
	end
end)