## Summary
- **Add a self-referencing `InterpolationHandler` to `ValueStringBuilder`** that writes directly into the builder's buffer — zero intermediate allocation, works with `stackalloc`-backed builders
- **Replace all `System.Text.StringBuilder` usage** across the codebase with `ValueStringBuilder`
- **Convert `ValueStringBuilder.Create()` to `stackalloc`** at 10 sites where output length is provably bounded
- **Convert manual `Dispose()` to `using var`** where possible, and hoist loop-scoped builders outside loops with `Reset()`
- **Convert verbose `Append()` chains to `Append($"...")`** interpolation for readability
- **Add comprehensive documentation** for string handling patterns
## InterpolationHandler Design
`ValueStringBuilder` is a `ref struct`, which creates challenges for C#'s interpolated string handler pattern:
- **`ref` fields to ref structs are not allowed** (CS9050)
- **`[InterpolatedStringHandlerArgument("")]` passes struct receivers by value**, not by ref
- **`ISelfInterpolatedStringHandler` requires boxing** ref structs into interface fields
**Solution: Copy-and-reconcile pattern.** The handler receives a value copy of the builder. The copy shares the same underlying `char` buffer (`Span` points to the same `stackalloc`/pooled memory), so writes go to the original buffer. `Append()` reconciles by `this = handler._builder`, updating `_length` and any buffer references changed by `Grow()`.
This is safe because:
- The game loop is single-threaded — no concurrent access between handler construction and reconciliation
- If `Grow()` occurs in the copy, the original's stale buffer isn't accessed until `Append()` replaces it
- `Dispose()` correctly returns the reconciled buffer to the pool
## Changes by Category
### ValueStringBuilder (`Projects/Server/Buffers/ValueStringBuilder.cs`)
- Added nested `InterpolationHandler` ref struct with copy-and-reconcile pattern
- Added `Append([InterpolatedStringHandlerArgument("")] scoped ref InterpolationHandler)` method
- Removed `RawInterpolatedStringHandler` overloads (new handler replaces them)
- All `AppendFormatted` overloads delegate to existing `Append` methods (no code duplication)
- Alignment support via direct private field access (nested type privilege)
### StringBuilder → ValueStringBuilder (15 files)
Replaced all `new StringBuilder()` with `ValueStringBuilder.Create()` or `stackalloc`:
- ConPVP games: KingOfTheHill, DoubleDom, CTF, BombingRun, TourneyMatch
- ConPVP infrastructure: Tournament, Participant, TourneyParticipant
- ConPVP gumps: ArenaGump, TournamentBracketGump, AcceptTeamGump, ConfirmSignupGump
- Commands: Handlers, Logging, Add
- Other: TownCrier, SpeechLogGump, TestCenter
Key patterns:
- `sb = new StringBuilder()` reassignment → `sb.Reset()`
- `sb.AppendFormat("{0:N0}", value)` → `sb.Append($"{value:N0}")`
- `sb.Append(x).Append(y)` chains → separate statements (VSB returns void)
### Create() → stackalloc (10 files)
Converted heap-allocated builders to stackalloc where output is bounded:
- ClientVersion (32), MapSelection (160), HouseRaffleStone (48)
- HolySense (96), UnholySense (96), ClientVerification (192)
- AcceptTeamGump (64), ConfirmSignupGump (64)
- BaseWeapon (160), BaseArmor (128)
### Loop optimizations (2 files)
Hoisted `ValueStringBuilder` creation outside loops with `Reset()` per iteration:
- TourneyMatch.cs: `using var` inside for loop → stackalloc before loop
- ArenaGump.cs: `Create()` + `Dispose()` per iteration → stackalloc before loop
### Append chain → interpolation (5 files)
Converted multi-line `Append()` chains to `Append($"...")`:
- BountyMessage.cs: title switch (6 cases), paragraph (15→1 Append), description lines, closing
- AcceptTeamGump, ConfirmSignupGump, TournamentBracketGump: tournament type strings
- AdminGump: comment/tag formatting in loops
### Documentation
- `dev-docs/string-handling.md`: Full reference — construction, interpolation, disposal, decision guide
- `dev-docs/claude-skills/modernuo-string-handling.md`: Claude skill with quick reference
- `CLAUDE.md`: Added rule 17 (no StringBuilder), dev-docs table entry, skills table entry
- `dev-docs/code-standards.md`: Updated memory management section
## Test Plan
- [x] `dotnet build` — 0 errors, 0 warnings
- [x] `dotnet test` — 940/940 tests pass
- [x] 28 ValueStringBuilder tests covering all reconciliation scenarios:
- Stackalloc no-grow, stackalloc with grow (→pool transition)
- Heap no-grow, heap with grow, heap double grow
- Pre-existing content with and without grow
- Sequential multiple `Append($"...")` calls
- Mixed plain + interpolated Append
- Empty interpolation, literal-only, format specifiers
- Null string holes, ISpanFormattable types
- Dispose after stackalloc→pool grow
# Bounty Boards
<img width="717" height="382" alt="image" src="https://github.com/user-attachments/assets/455e5206-47d8-4449-805c-19b143d059e5" />
<img width="918" height="637" alt="image" src="https://github.com/user-attachments/assets/e78e1ca2-62b8-4abf-8f69-21438bb1b759" />
<img width="340" height="296" alt="image" src="https://github.com/user-attachments/assets/fd17d7e6-8c53-47df-ac58-a89ea3ef665e" />
## Setup
* Setup as part of decorate when bounty system is enabled
* Several bounty board locations with a WarriorGuard spawner in front of the board. Guard spawns and idles around 5 range.
## Tests
### ReportBountyMurdererGump
* Follows same behaviour as ReportMurdererGump
* Extracted common logic
* Didn't use staticgump due to several dynamic parts including input
* Optional bounty with validation >0 and <bankbox.total
* Murder report is honored either way
### Bounty boards
* Open bounty board with many bounties, no bounties
* Keep a bounty board open, invalidate a bounty by turning in the head, then try to click on the post of the now invalid post. As expected: does nothing
* Bounty messages use the last murder time as their post date and expire in 14 days
* Bounty boards/messages are not reliant on serialization; they use serialized fields from MurderContext to build messages when clicked.
* Bounty messages use synthetic serials so they do not have to persist bounty messages as items. They are constructed and sent as raw packets when needed.
* Players only appear on the bounty board if they are a murderer (though a non-murderer can technically still have a bounty if they decayed kills)
* Tested skin/hair color descriptions vs a dozen spot checks
### Head turn in behaviour
* Guard accepts head
* Bounty -> gives bounty
* No bounty -> generic response
* Expired head (24h) -> generic response
NOTE: CUO "latest" has a bug with bounty/bulletinmessages that causes overflow outside of the container. It has nothing to do with this PR. It is fixed here in CUO https://github.com/ClassicUO/ClassicUO/pull/1871
# Murderer title
Bounty system and "murderer" title eliminated in [pub16](https://uo.com/wiki/ultima-online-wiki/technical/previous-publishes/2002-2/publish-16-part-2-5-23rd-july/). So UO:LBR and before had bounties and murderer title.
# Pre-T2A caveat
There were differences in pre-T2A, but this cannot be currently implemented because we do not have any pre-T2A systems in general, so at least for now, behavior is consistent with later eras. Pre-T2A was a whole other ballgame, but the bounty system still worked similarly.
## Summary
- Adds `Mobile.Murderer` virtual property and consolidates kill-threshold checks across the codebase
- Tracks ping-pong count: how many times a player crosses the 5-kill murderer threshold (T2A/UOR/UOTD only, disabled on LBR+)
- Adds `[CommandProperty]` to view a player's ping-pong count via the admin panel
- After enough ping-pongs, player is permanently flagged as a murderer regardless of kill count
- Accounts for perma-red players with low kills in murderer status transition notifications
- Implements era-appropriate "I must consider my sins" speech responses:
- **T2A**: contextual cliloc flavor text (502122–502126)
- **UOR–AOS**: raw short/long-term murder counts + ping-pong count if applicable
- **SE+**: localized stats message (1114370)
- Refactors kill-report logic out of `Keywords.cs` into `PlayerMurderSystem.ReportKillsToSelf`
## Testing
- [x] Thoroughly tested and self reviewed
- [x] Test T2A "I must consider my sins" behaviour over all scenarios.
- [x] Test UOR "I must consider my sins" behaviour over all scenarios.
- [x] Test that LBR does not have ping pongs enabled (I must consider my sins)
- [x] Test serialization cross over from v0 -> v1 increments 1 ping pong if player is already red.
## Notes
* Manually setting kills to 5 does not trigger a ping pong, it must go through the actual murder system. This includes if the kills were manually set to 5 and then migrated (as manually setting kills to 5 never adds the player into the murder system - it only happens via ReportMurderer). This is arguably a bug in the existing system, but one that currently only ever happens via staff interaction.
* Thieves guild SuspendOnMurder specifically checks for kills > 0. This means a person with 0 shorts but 5 ping pongs (flagged as murderer) can steal. This may be accurate, as according to a forum post this is how it works on UOSA which is the T2A gold standard.
* This doesn't implement Pre-T2A behaviour which should be that "I must consider my sins" does nothing at all. The reason I didn't implement it for Pre-T2A is then it 100% have to sit behind a feature flag. I don't mind adding it as a feature flag, just let me know.
### Summary
- Adds [Code Generated Events](https://github.com/modernuo/CodeGeneratedEvents)
- Removes EventSink.PlayerDeath
- Adds `PlayerDeathEvent` and `CreatureDeathEvent` using code generated events
> [!Important]
> **Developer Note**
> Use `[OnEvent(nameof(PlayerMobile.PlayerDeathEvent))]` instead of `EventSink.PlayerDeath` delegate
> Check this commit for examples of how to use this.
### Summary
- [X] Fixed a bug where entity persistence was serialized out of order, causing world corruption.
- [X] Fixed LastSerialized not being utilized properly and dangling references still becoming an issue.
- [X] Added a new `GenericEntityPersistence<T>` type to encapsulate `ISerializable` serialization.
- [X] Removing the custom logic and moved Items, Mobiles, Guilds, and Accounts to GenericEntityPersistence.
- [X] Changed serialization to use the singleton pattern to reduce calling methods from stored variables.
## 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.
## MAJOR CHANGE (API BREAKING)
Added a player murder system to facilitate reporting murders. This should make it easier to extend to create a bounty system or other related game content. Player murders will be saved in a folder called _PlayerMurders_.
### Motivation
The motivation was two-fold, performance, and bug fixes.
First, murders are one of two systems that do a pre-world-save check on _every mobile in the game_ to decay kills and set their expiring murders. This is taxing since it freezes the world and makes world saves take longer. Every mobile has ShortTermMurders even though it is a player concept. And next, 90%+ of players are not murderers but had an ever increasing MurderElapse time that was being tracked against GameTime. These properties were also serialized unnecessarily for all mobs.
Second, when I tried to optimize/refactor the code, it was obvious that the system has bugs.
### Major API Changes
- [X] Created a player murder system and moved `ShortTermMurders`, `ShortTermElapse`, and `LongTermElapse` to the system.
- [X] Added convenience property `PlayerMobile.ShortTermMurders`.
- [X] Added convenience properties `PlayerMobile.ShortTermMurderExpiration` and `PlayerMobile.LongTermMurderExpiration`
- [X] Moved ReportMurdererGump.cs
- [X] Adds an `EventSink.PlayerDeleted` event.
### Notes
The system currently does not support NPCs. To support expiring murders on NPCs I highly recommend a different architecture for large servers (500k+ mobs including players). Specifically switching from looping through all MurderContext to a time-order link list.
