Item = {
    list = {}
}

setmetatable(Item, {
    __call = function (self, ...)
        return self:create(...)
    end
})

function Item:create(name, weight, category)
    if Item.list[name] then
        return Item.list[name]
    end

    local new = {
        name = name,
        weight = weight,
        category = category
    }
    setmetatable(new, {__index = Item})
    Item.list[name] = new

    return new
end

function Item.exists(name)
    return Item.list[name] and true or false
end

function Item:getWeight()
    return self.weight
end

function Item:setWeight(weight)
    self.weight = weight
end

function Item:getName()
    return self.name
end

function Item:getCategory()
    return self.category
end

function Item:setCategory(category)
    self.category = category
end

-- Create consumable items
Item("Apple", 2, "Consumable")
Item("Banana", 3, "Consumable")
Item("Orange", 1, "Consumable")
Item("Water", 10, "Consumable")
Item("Cola", 8, "Consumable")

-- Create 2 weapons
Item("M4A1", 50, "Weapon")
Item("MP5", 30, "Weapon")