### Summary
Container enumeration is in dire need of optimization. Thanks to @stefanomerotta for initiating this work with PR #1443. This PR handles a small part of what Stefan started. Also included are some bug fixes.
### Method Signatures
```cs
// Use with foreach without moving/deleting items
FindItemsByTypeEnumerator<T> FindItemsByType<T>(bool recurse = true, Predicate<T> predicate = null)
// Use with foreach when moving/deleting items
QueuedItemsEnumerator<T> EnumerateItemsByType<T>(bool recurse = true, Predicate<T> predicate = null)
// Use when iterating multiple times or queuing
PooledRefQueue<T> QueueItemsByType<T>(bool recurse = true, Predicate<T> predicate = null)
// Use when iterating multiples times or manipulating elements without traversing
PooledRefList<T> ListItemsByType<T>(bool recurse = true, Predicate<T> predicate = null)
```
* `FindItemsByType<T>` has changed from returning `List<T>` to `FindItemsByTypeEnumerator<T>` - This method is not safe to use in situations where an item may get consumed, deleted, or moved.
* `EnumerateItemsByType<T>` was added as a safe way to iterate and manipulate items.
* **Note**: EnumerateItemsByType will _completely traverse the container_ before iteration starts because it uses `QueueItemsByType` under the hood.
* `QueueItemsByType<T>` and `ListItemsByType<T>` was added to return a queue or list of items to iterate multiple times and manipulate the items. This isn't the most efficient since it uses a predicate and can result in 2 or 3 total iterations unnecessarily.
### Bug Fixes
- [X] Fishing had an error in the random check that may have caused slight bias.
## Overhaul to Stamina (Overweight) System
### Added configurations
```json
{
"settings": {
"stamina.enableMountStamina": "True",
"stamina.cannotMoveWhenFatigued": "True",
"stamina.stonesPerOverweightLoss": "25",
"stamina.stonesOverweightAllowance": "4",
"stamina.baseOverweightLoss": "5",
"stamina.additionalLossWhenBelow": "0.1",
"stamina.mountLastMoveStepsReset": "01:00:00:00",
"stamina.enableMountStamina": "True",
"stamina.useMountStaminaOnlyWhenOverloaded": "False",
},
}
```
- `stamina.cannotMoveWhenFatigued` - By default, Pre-AOS expansions will outright block a player if they are fatigued. A player is fatigued when they run out of stamina by any mechanism.
- `stamina.stonesPerOverweightLoss` - The amount of stamina lost for every X stones above overweight. Example, if a person is overweight 28 stones overweight, then there there is 1 additional stamina. 28 / 25 = 1 (no decimals, no rounding)
- `stamina.stonesOverweightAllowance` - The number of stones allowed before overweight penalties take affect. This _does not_ substract from the overweight stones calculation.
- `stamina.baseOverweightLoss` - The base amount of stamina loss for being overweight. While running, the final amount is multiplied by 2. If mount stamina is turned off, then the final amount is divided by 3 while mounted.
### Mount stamina
Mounts have a new property `StepsMax` to determine the maximum steps they can take before being fatigued. To regain steps, the player _must stay on the mount and not move_ (per OSI). The gain rates are configurable. If a mount is dismounted, or the player logs off, the mount is considered inactive and mounts regain all of their steps after _24 hours_.
### Changes to player stamina
Players now have a proper inactivity time reset for their steps. If a player is idle for 16 seconds (including logging off, or the server being offline), then the steps counter is rest.
### Developer Notes
- `StepsTaken` - This field has been removed. It was not serialized and could not be used reliably. If a developer was using it, then the recommendation is to build a mechanism to track total steps another way.
- `IHasStamina` - This new interface was added and currently `IMount` and `PlayerMobile` are valid types.
Important: Entities that are sent to the StaminaSystem for tracking (mounts, players, or something else), must be an `ISerializable` to be serialized properly. If they are not, then the serialization system will record a null, and nothing will be deserialized upon world load. No errors will be given.
## Changes
- [X] Adds OPL convenience methods
- `opl.Add(cliloc, value)` and `opl.Add(value)` - value as an integer or string works just like `opl.Add(cliloc, $"{value}")`
- `opl.AddLocalized(cliloc, clilocValue)` - works the same as `opl.Add(cliloc, $"#{clilocValue}");`
- [X] Simplifies basic `list.Add()` situations
- [X] Changes cliloc as an argument so it works with custom IPropertyList implementations (HTML)
- [X] Fixes plants so they support the old localization and new (changed in 7.0.12.0+)
- [X] Exposes more methods to override for Item to make creating custom OPL possible.
## Important Notes
* Using a ternary as an argument, like this `opl.Add(number, showType ? $"{type}\t{value}" : $"{value}");` _will not use the correct string interpolation_. This means if you use a custom PropertyList (for HTML or some other purpose), the property list won't be localized properly.
* All localization values must be interpolated, even if they are literal strings, or integers. Example: `opl.Add(number, $"{"Charges"}\t{m_Charges}");` is correct. Using the following: `$"Charges\t{m_Charges}"` will not work for custom PropertyList implementations!
## Breaking Changes (New API)
ObjectPropertyList supports the following API:
```cs
list.Add(500000);
list.Add(500001, stringArgument);
list.Add("Some text");
list.Add($"Some text with {argument}");
list.Add(500002, $"{arg1}\t{arg2}");
```
## Notes
1. All API uses that require a formatter like this:
```cs
list.Add(500002, "{0}\t{1}", arg1, arg2);
```
Should be changed to use string interpolation, for example:
```cs
list.Add(500002, $"{arg1}\t{arg2}");
```
2. The following paradigm should no longer be used:
```cs
list.Add(1061170, prop.ToString()); // strength requirement ~1_val~
```
The new string interpolation API will avoid having to convert the argument to a string before writing it to the packet. Instead use the following:
```cs
list.Add(1061170, $"{prop}"); // strength requirement ~1_val~
```
### Benchmarks
```cs
| Method | Mean | Error | StdDev | Gen 0 | Allocated |
|------------------------------- |---------:|--------:|--------:|-------:|----------:|
| BenchmarkOldOPL | 241.0 ns | 0.56 ns | 0.47 ns | 0.0105 | 88 B |
| BenchmarkStringInterpolatedOPL | 199.9 ns | 2.44 ns | 2.39 ns | - | - |
```
### Changes
- [X] Removes crash in STArray.Return when array is null.
- [X] Fixes NPE in OPL when entity is null. Serial in packet will be 0 when entity is null.
- [X] Fixes NPE in AosAttributes when Parent is null.
- [X] Changes OPL to use string interpolation.
- [X] Introduces `IPropertyList` to allow extending PropertyList for other uses.
* Removes scaled speed by dex for monsters
* Changes scaled speed by dex for pets (HS+ expansion) to be 400ms -> 100ms between 50 -> 200 dex
* Removes speed changes that were broken for various mobs
* Combines "Legacy" speed and renames the class to `NPCSpeeds`
* Creates speed "classes" (slow, medium, fast, very fast)
* Introduces a new overridable property `SpeedClass`. Register a new speed class using `NPCSpeeds.Register()` and then set the speed class to bulk/mass apply speeds.
Order of speed determination:
1. SpeedMod
2. SpeedClass property (not null)
3. SpeedClass entry in Data\npc-speeds.json for that type
4. "Fast" (200ms Active, 400ms Passive)
* Adds the following configurations:
* `movement.delay.npcMinDelay` - 0.1 - Pets or Non-monster NPCs
* `movement.delay.npcMaxDelay` - 0.4 - Pets or Non-monster NPCs
* `movement.delay.monsterMinDelay` - 0.4 - Non-pet Monsters or NPC vs Player Combat
* `movement.delay.monsterMaxDelay` - 0.8 - Non-pet Monsters or NPC vs Player Combat
* `movement.delay.monsterMinDex` - 150 - Dex maximum for delay by dex
* `movement.delay.MinDex` - 190 - Dex maximum for delay by dex
### Changes/Fixes:
* Adds timer pooling.
* Allows pool to be configurable in ModernUO.json
* Pool replenishes itself asynchronously if depleted.
* Fixes an issue with barkeeps and town criers
* Fixes an issue with incognito buff icons not being removed
* Fixes an issue with polymorph name mod not being removed
* Fixes several places where timers go on forever even after an object is deleted, keeping a reference (memory leak)
* Eliminates the timer for MiningCart altogether.
* Deletes `AcidSlime` since it is a duplicate of `PoolOfAcid`
* Fixes HonorableExecution and standardizes the code for other Bushido moves.
## Changes to the Timer API:
```cs
public class Timer
{
// Creates a timer that will be returned to the pool once execution stops.
public static void StartTimer(Action callback);
public static void StartTimer(TimeSpan delay, Action callback);
public static void StartTimer(TimeSpan delay, TimeSpan interval, Action callback);
public static void StartTimer(TimeSpan interval, int count, Action callback);
public static void StartTimer(TimeSpan delay, TimeSpan interval, int count, Action callback);
// Creates a timer and returns a token for more control. Requires manual cancellation in order for the timer to be returned to the pool.
// If the token is dereferenced, the timer will be dereferenced too. While not returning a timer to the pool is not considered hazardous, it does defeat the purpose of pooled timers.
public static void StartTimer(Action callback, out TimerExecutionToken token);
public static void StartTimer(TimeSpan delay, Action callback, out TimerExecutionToken token);
public static void StartTimer(TimeSpan delay, TimeSpan interval, Action callback, out TimerExecutionToken token);
public static void StartTimer(TimeSpan interval, int count, Action callback, out TimerExecutionToken token);
public static void StartTimer(TimeSpan delay, TimeSpan interval, int count, Action callback, out TimerExecutionToken token);
// If you aren't sure how to use the API above, or you don't care about performance, then you can use the old RunUO Timer.DelayCall
public static DelayCallTimer DelayCall(Action callback);
public static DelayCallTimer DelayCall(TimeSpan delay, Action callback);
public static DelayCallTimer DelayCall(TimeSpan delay, TimeSpan interval, Action callback);
public static DelayCallTimer DelayCall(TimeSpan interval, int count, Action callback);
public static DelayCallTimer DelayCall(TimeSpan delay, TimeSpan interval, int count, Action callback);
}
public struct TimerExecutionToken
{
public bool Running { get; }
public int Index { get; }
public int RemainingCount { get; }
public DateTime Next { get; }
}
```
## When to use `TimerExecutionToken`?
Use tokens when you want to gain the performance benefit of using a pooled timer, but you need one of the following:
* Access to the next time the timer will tick:`token.Next`
* Access to which interval, how many intervals there are, or how many are remaining: `token.Index`, `token.Count`, and `token.RemainingCount`
* Stop a timer manually.
* Determine if the timer is running: `timer.Running`
* See notes below about requirements for using tokens!
## Notes about using the TimerExecutionToken:
When you opt-in to receive a token, you must call `Cancel()` to return the timer. This can be done inside of the callback, or outside of the callback at any time.
If this is not called and your timer is an infinite interval, then you will create a potential memory leak, or null pointer exception in your callback.
If the timer ends and is stopped, but cancel is not called, then the timer will never return to the pool and stay referenced until the token is deleted or cancel is called. (Memory leak)
## Is this thread safe?
No. The ModernUO timer system is not thread safe at all. If you require a thread safe timer system, contact me and I'll help adapt this system. Keep in mind that there is a massive performance hit to make this thread safe when there are literally no use cases for it.
If you need to synchronize execution, meaning you want to execute code from another thread on the core thread. Let's say you have a discord bot that is pushing commands to the game server. Then use `EventLoopContext.Post(SendOrPostCallback callback, object state);`.
- [X] Caches DateTime.NowUtc on the game loop (not other threads)
- [X] Replaces all locations where it makes sense
- [X] Adds Min/Max for `IComparable` (TimeSpan, DateTimes, etc)
Closes#261
- [X] Fixes an issue where a buffer smaller than 8 bytes would not double with enough space in some cases.
- [X] Fixes an issue with dupe copying the savebuffer reference (ugh).
- [X] Streamlines the IGenericWriter API to use better generics.
- [X] Streamlines the IGenericReader API to use better generics.
- [X] Forces `tidying` of a List/HashSet to be done externally since Writers/Readers should not have side effects.
- [X] Fixes an issue where Tidying a list didn't TrimExcess, causing memory leaks.
- [X] Reverted the meaning of `World.Running` to specifically refer to any world state post world loading.
- NOTE: Do not use this if you want to block on world saves. Instead use checks against `WorldState.Saving` states.
- [X] Fixes an issue with serializing negative DateTime deltas.
- [X] Fixes a potential issue with serializing non-UTC DateTime.
Bumps release version
- [X] Removes some string allocations (e.g. split)
- [X] Optimizes some collections
- [X] Converts insensitive to extension methods of built-ins.
- [X] Adds ordinal (case sensitive) string helpers
- [X] Fixes conditionals for in-game commands so they use Ordinal comparisons.
- [X] Replaces ToLower.Contains with InsensitiveContains
- [X] Adds ValueStringBuilder
- [X] Implements ValueStringBuilder in a few places where it makes sense
- [X] Removes the redundant Wrap function and replaces it with an optimized version
- [X] Fixes list conversions in Utility
Closes#351
Bumps release version
