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Beautiful.

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Once we have set up our store and reducer, now we can zero in on the specifics of the producer.

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And when it comes to producer, again, like I previously already mentioned, producer function is used

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to update our store and it takes two arguments state and action.

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And you can think of state as an old state or state before the update and action of what happened in

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your application or what kind of update you would want to make to your store.

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Now, easy way of thinking of actions is thinking what is the user doing?

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So, for example, we have the card.

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So what if a user would like to click on the increase?

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But well, we would set up the functionality where if that happens, then of course we increase the

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amount of items.

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We have an ID card.

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We also set up to total and all that.

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So the same would work if we decrease, if we remove and along those lines.

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Now, of course, since there are arguments, you can technically name them however you like, but a

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common practice is naming them state and action.

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Now, once we pass in our parameters, then I would like to console them just so we can see what is

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happening.

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So I'm going to go with the object in this case because I think it's going to be more representative

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and I'm going to go state and action.

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So once we cancel, like both of them, we notice something really interesting.

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So as far as state at the moment, it is undefined and then I'm not going to cover the action right

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now.

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This would be just the default action that is passed into initialized everything from the redox.

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So later we were going to create our own actions.

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But at this point in time, redacts just passes a default action which initializes everything.

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So we our state, we have our action.

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But of course, now we need to deal with the fact that our state at the moment is undefined.

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So what's up with that?

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When you say why don't we have to create store, we can pass in the second argument, and that would

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be our initial store, of course, we would still need to set it up.

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So, for example, above the register, I can say initial store and I'm going to create it as a variable,

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of course, const initial store, initial store.

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And for the time being there will be equal to an object.

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And then within the object I'm going to have the current property and the count will be equal to zero.

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Now, like I said, the second argument and a great store is where we pass in our initial store.

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So I'm going to go with initial store and now in a console, we should still see our default action.

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That would be that funny action with the type and then state now is count.

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So in the beginning it was undefined because we didn't pass any kind of initial value.

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But then, of course, once we set up our initial store, now this is our initial state of the application.

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And then when it comes to our producer, we have one of the two options.

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Either we are going to return updated state.

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So state after the action happened, for example, again, user decided to remove the item.

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So we're going to have functionality that checks for that action that actually happened.

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Then, of course, we're going to do our calculations, remove that product from the state, and then

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return a new state without that product.

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But always, always has a default.

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You should return the old state so state before the update.

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So if, for example, some kind of action happen and you are not checking for that action, you should

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always, always return to state before the update.

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That's why in the bottom, I'm going to write return state, essentially what I'm doing, as I'm saying.

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All right.

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I'm going to be checking for the actions.

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If none of the actions match to whatever action just happened in my application, then I'm just going

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to return the state the way it was before the update.