Mirror: Cycle injector transfer amount on alt. use (#178)

## Mirror of PR #25566: [Cycle injector transfer amount on alt.
use](space-wizards/space-station-14#25566) from
<img src="https://avatars.githubusercontent.com/u/10567778?v=4"
alt="space-wizards" width="22"/>
[space-wizards](https://github.com/space-wizards)/[space-station-14](https://github.com/space-wizards/space-station-14)

###### `ad6ac73f6f41d1cbd3fe80a43c8bf4b83e03f392`

PR opened by <img
src="https://avatars.githubusercontent.com/u/68151557?v=4"
width="16"/><a href="https://github.com/veprolet"> veprolet</a> at
2024-02-25 19:37:49 UTC

---

PR changed 3 files with 26 additions and 3 deletions.

The PR had the following labels:
- Status: Needs Review


---

<details open="true"><summary><h1>Original Body</h1></summary>

> ## About the PR
> When the user tries to use alternative interaction on an injector
capable of changing transfer volume, this will cycle between the maximal
and minimal transfer amount (defaulting to maximum if the value was
in-between the extremes).
> 
> The interaction is only available with in-hand usage or empty-handed
usage. This is deliberate (but not necessarily correct).
> The interaction is only implemented for injectors and not arbitrary
containers capable of solution transfers. This is to limit the scope of
this PR.
> 
> ## Why / Balance
> Changing the transfer amount was only possible using the context menu.
This was difficult and slow, but this tedium didn't seem to be a
valuable part of the gameplay experience.
> 
> Instead of cycling over all the possible transfer amounts, the choice
has been made to only cycle between the two extremes. This is for two
reasons:
> - Scalability: If this is merged, we'll probably want the same
behavior for the other solution containers like jugs. It would be very
tedious (probably more tedious than using the context menu) to cycle to
the correct transfer amount with more available transfer amount steps.
It would also be IMO unintuitive to have a different behavior between
the two types of solution containers.
> - Simplicity: It is easier to reason about the next state this way.
Otherwise, one would have to figure out how many times to perform the
interaction to cycle to the desired amount, which involves knowing the
total number of steps for each injector/container, order of the current
step and modular arithmetic (or just cycling until you are at the
correct one, which is slow, error-prone and frustrating whenever you
overshoot).
> 
> This decision has obviously some tradeoffs, but I feel like those are
manageable. If you need to transfer the in-between amounts, you can
usually switch to the minimal amount (I assume the property of
in-between amounts being a multiple of the minimum will be upheld in the
future) and click a few times. This is generally as tedious or less
tedious than cycling the amounts. There are some instances where you
can't do that. One example would be manual mixing of the advanced brute
medications. This is a niche use-case and can be still solved using the
context menu verb system and is supposed to be a bit more difficult
anyway.
> 
> This also makes the alternative interaction a bit less predictable, as
it no longer always uses the first context menu verb. I think the
interaction is similar enough and inconsequential enough to justify
this.
> 
> It makes the syringe marginally more powerful, but as this doesn't
introduce any previously unavailable actions, I believe this to be
perfectly acceptable and heavily outweighed by the convenience.
> 
> ## Technical details
> ~~This introduces a new concept of "special alternative" interactions.
Those interactions have their own events and handlers.~~
> 
> Please scrutinize the code hard ~~, because it touches some quite
fundamental parts of the game, and~~ I'm not too knowledgeable about C#
or the conventions of this repo. I tried to follow guidelines where
possible while not impacting the existing code too much, but maybe this
leads to too much weirdness in some places.
> 
> ## Media
>
![optimized](https://github.com/space-wizards/space-station-14/assets/68151557/c445b535-e4c6-49ff-b712-d540dd7fe57b)
> 
> - [X] I acknowledge that I have no idea how to showcase or record this
feature well, **or** I'm trying my best.
> 
> ## Breaking changes
> N/A
> 
> **Changelog**
> 🆑
> - tweak: Injectors like the syringe can now toggle their transfer
amount using alternative interactions.
> 


</details>

Co-authored-by: SimpleStation14 <Unknown>

Content.Shared/Chemistry/Components/InjectorComponent.cs

@@ -53,8 +53,7 @@ public sealed partial class InjectorComponent : Component
     ///     The maximum amount of solution that can be transferred at once from this solution.
     /// </summary>
     [DataField("maxTransferAmount")]
-    [ViewVariables(VVAccess.ReadWrite)]
-    public FixedPoint2 MaximumTransferAmount = FixedPoint2.New(50);
+    public FixedPoint2 MaximumTransferAmount = FixedPoint2.New(15);
 
     /// <summary>
     /// Amount to inject or draw on each usage. If the injector is inject only, it will

Content.Shared/Chemistry/EntitySystems/SharedInjectorSystem.cs

@@ -39,12 +39,34 @@ private void AddSetTransferVerbs(Entity<InjectorComponent> entity, ref GetVerbsE
 
         if (!HasComp<ActorComponent>(args.User))
             return;
+        var user = args.User;
 
         var (_, component) = entity;
 
-        // Add specific transfer verbs according to the container's size
+        var min = component.MinimumTransferAmount;
+        var max = component.MaximumTransferAmount;
+        var cur = component.TransferAmount;
+        var toggleAmount = cur == max ? min : max;
+
         var priority = 0;
-        var user = args.User;
+        AlternativeVerb toggleVerb = new()
+        {
+            Text = Loc.GetString("comp-solution-transfer-verb-toggle", ("amount", toggleAmount)),
+            Category = VerbCategory.SetTransferAmount,
+            Act = () =>
+            {
+                component.TransferAmount = toggleAmount;
+                Popup.PopupClient(Loc.GetString("comp-solution-transfer-set-amount", ("amount", toggleAmount)), user, user);
+                Dirty(entity);
+            },
+
+            Priority = priority
+        };
+        args.Verbs.Add(toggleVerb);
+
+        priority -= 1;
+
+        // Add specific transfer verbs according to the container's size
         foreach (var amount in TransferAmounts)
         {
             if (amount < component.MinimumTransferAmount || amount > component.MaximumTransferAmount)

Resources/Locale/en-US/chemistry/components/solution-transfer-component.ftl

@@ -11,6 +11,7 @@ comp-solution-transfer-is-full = {THE($target)} is full!
 ## Displayed in change transfer amount verb's name
 comp-solution-transfer-verb-custom-amount = Custom
 comp-solution-transfer-verb-amount = {$amount}u
+comp-solution-transfer-verb-toggle = Toggle to {$amount}u
 
 ## Displayed after you successfully change a solution's amount using the BUI
 comp-solution-transfer-set-amount = Transfer amount set to {$amount}u.