ModernUO/Projects/UOContent/Engines/Spawners/Json/SpawnerDto.cs
Kamron Batman d8a64f3316
refactor(spawners): replace DynamicJson with typed SpawnerDto records (#2505)
## Summary

Removes the dated `DynamicJson` JSON helper and migrates spawner JSON (de)serialization to a polymorphic `record SpawnerDto` hierarchy. `DynamicJson` was the last remaining consumer (regions moved off it in #1400).

The key correctness improvement: **System.Text.Json deserializes plain DTO records, never a live `Item`.** Previously, deserializing directly into an `Item` meant STJ constructed world-registered objects *before* the data was validated — a malformed/hand-edited spawn file could leave orphaned spawner Items in the world save. Now a parse failure is GC-only; `dto.ToSpawner()` constructs the spawner only from a fully-validated DTO and self-cleans on failure.

## What changed

- **New:** `SpawnerDto` (abstract) + `SpawnerDataDto` / `RegionSpawnerDto` / `ProximitySpawnerDto`, each marked with a reusable `[JsonDiscoverableType]` opt-in attribute. Auto-discovered at the `Configure` phase — no manual registration list (avoids the regions `Register<T>()` footgun), open to custom spawner subtypes.
- **Symmetric mapping:** `BaseSpawner.ToDto()` (export) ⇄ `SpawnerDto.ToSpawner()` (import). `ToSpawner()` deletes-and-rethrows on any failure, so the importer can never orphan an Item.
- **`SpawnerJsonSerializer`** wires `$type` polymorphism on the `SpawnerDto` root with loud collision/constructibility validation.
- **Import/export commands** rewired to the typed DTO path (reflection `FindTypeByName`/`CreateInstance` removed).
- **Data migration:** the 109 `Distribution/Data/Spawns/**` files moved from `"type"`→`"$type"` and legacy `homeRange`→`spawnBounds`. The runtime still *reads* legacy `homeRange` for external files. The `homeRange→spawnBounds` formula is proven equivalent to the runtime conversion (`BoundsEquivalenceTests`, hr=0/1/3/7).
- **Deleted:** `Projects/Server/Json/DynamicJson.cs`.

Sparse export output matches the legacy `ToJson` (nullable DTO properties + `WhenWritingNull`). Binary world-save serialization is untouched.

## Tests

- DTO round-trip per spawner type; sparse-default omission; legacy `homeRange` read; export/import file round-trip.
- `Import_MalformedFile_LeaksNoWorldItems` — proves a mid-array parse failure constructs zero world Items.
- `AllSpawnFilesLoadTests` — every migrated spawn file deserializes and builds.
- Duplicate-discriminator validation.
- UOContent.Tests 485/485, Server.Tests 710/710, build clean.

## Follow-up (not in this PR)

`Rectangle3DConverter.Write` (in `Projects/Server/`) omits `z1/z2` when `Start.Z == -128`, so a future server-side export of a `homeRange`-style spawner round-trips depth 256→255. Pre-existing and out of scope here (Server change); the migrated data reads correctly. Worth a separate small converter PR.
2026-06-25 23:24:45 -07:00

217 lines
6.8 KiB
C#

/*************************************************************************
* ModernUO *
* Copyright 2019-2026 - ModernUO Development Team *
* Email: hi@modernuo.com *
* File: SpawnerDto.cs *
* *
* This program is free software: you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation, either version 3 of the License, or *
* (at your option) any later version. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program. If not, see <http://www.gnu.org/licenses/>. *
*************************************************************************/
using System;
using System.Collections.Generic;
using System.Text.Json.Serialization;
using Server.Json;
using Server.Regions;
namespace Server.Engines.Spawners;
/// <summary>
/// Plain data carrier for spawner JSON. STJ deserializes into these records (never a live Item),
/// so a malformed file fails as GC only; <see cref="ToSpawner"/> builds the spawner from a
/// validated DTO. Options use <c>WhenWritingDefault</c>; mandatory fields force-write via
/// <c>[JsonIgnore(Condition = Never)]</c> and <c>[JsonPropertyOrder]</c> sets the on-disk order.
/// </summary>
public abstract record SpawnerDto
{
// Mandatory: always written.
[JsonPropertyName("guid")]
[JsonPropertyOrder(0)]
[JsonIgnore(Condition = JsonIgnoreCondition.Never)]
public Guid Guid { get; init; }
[JsonPropertyName("name")]
[JsonPropertyOrder(1)]
public string Name { get; init; }
[JsonPropertyName("location")]
[JsonPropertyOrder(2)]
[JsonIgnore(Condition = JsonIgnoreCondition.Never)]
[JsonConverter(typeof(Point3DArrayConverter))]
public Point3D Location { get; init; }
[JsonPropertyName("map")]
[JsonPropertyOrder(3)]
[JsonIgnore(Condition = JsonIgnoreCondition.Never)]
public Map Map { get; init; }
[JsonPropertyName("count")]
[JsonPropertyOrder(4)]
[JsonIgnore(Condition = JsonIgnoreCondition.Never)]
public int Count { get; init; }
[JsonPropertyName("minDelay")]
[JsonPropertyOrder(5)]
[JsonIgnore(Condition = JsonIgnoreCondition.Never)]
public TimeSpan MinDelay { get; init; }
[JsonPropertyName("maxDelay")]
[JsonPropertyOrder(6)]
[JsonIgnore(Condition = JsonIgnoreCondition.Never)]
public TimeSpan MaxDelay { get; init; }
// Optional: omitted at default (spawnBounds/region live on the subtypes at order 8).
[JsonPropertyName("team")]
[JsonPropertyOrder(7)]
public int Team { get; init; }
[JsonPropertyName("walkingRange")]
[JsonPropertyOrder(9)]
public int WalkingRange { get; init; }
[JsonPropertyName("entries")]
[JsonPropertyOrder(10)]
[JsonIgnore(Condition = JsonIgnoreCondition.Never)]
public List<SpawnerEntry> Entries { get; init; }
[JsonPropertyName("spawnLocationIsHome")]
[JsonPropertyOrder(11)]
public bool SpawnLocationIsHome { get; init; }
[JsonPropertyName("spawnPositionMode")]
[JsonPropertyOrder(12)]
public SpawnPositionMode SpawnPositionMode { get; init; }
[JsonPropertyName("maxSpawnAttempts")]
[JsonPropertyOrder(13)]
public int MaxSpawnAttempts { get; init; }
// Compact square-bounds form, -1 when absent. Written only when >= 0 (ShouldSerialize, since 0
// is a valid radius WhenWritingDefault cannot emit); reconstructs SpawnBounds in ApplyDto.
[JsonPropertyName("homeRange")]
[JsonPropertyOrder(8)]
public int HomeRange { get; init; } = -1;
/// <summary>Constructs the empty concrete spawner Item for this DTO.</summary>
protected abstract BaseSpawner CreateEmpty();
/// <summary>Builds and populates the live spawner. Override to apply subtype fields after base.</summary>
public virtual BaseSpawner ToSpawner()
{
var spawner = CreateEmpty();
try
{
spawner.ApplyDto(this);
return spawner;
}
catch
{
// CreateEmpty registered the Item; delete it if population throws so no orphan escapes.
spawner.Delete();
throw;
}
}
}
[JsonDiscoverableType("Spawner")]
public sealed record SpawnerDataDto : SpawnerDto
{
[JsonPropertyName("spawnBounds")]
[JsonPropertyOrder(8)]
public Rectangle3D SpawnBounds { get; init; }
protected override BaseSpawner CreateEmpty() => new Spawner();
public override BaseSpawner ToSpawner()
{
var spawner = (Spawner)base.ToSpawner();
try
{
if (SpawnBounds != default)
{
spawner.SpawnBounds = SpawnBounds;
}
return spawner;
}
catch
{
spawner.Delete();
throw;
}
}
}
[JsonDiscoverableType("RegionSpawner")]
public sealed record RegionSpawnerDto : SpawnerDto
{
[JsonPropertyName("region")]
[JsonPropertyOrder(8)]
public string Region { get; init; }
protected override BaseSpawner CreateEmpty() => new RegionSpawner();
public override BaseSpawner ToSpawner()
{
var spawner = (RegionSpawner)base.ToSpawner();
try
{
spawner.SpawnRegion = Server.Region.Find(Region, Map) as BaseRegion;
return spawner;
}
catch
{
spawner.Delete();
throw;
}
}
}
[JsonDiscoverableType("ProximitySpawner")]
public sealed record ProximitySpawnerDto : SpawnerDto
{
[JsonPropertyName("spawnBounds")]
[JsonPropertyOrder(8)]
public Rectangle3D SpawnBounds { get; init; }
[JsonPropertyName("triggerRange")]
[JsonPropertyOrder(14)]
public int TriggerRange { get; init; }
[JsonPropertyName("spawnMessage")]
[JsonPropertyOrder(15)]
public TextDefinition SpawnMessage { get; init; }
[JsonPropertyName("instant")]
[JsonPropertyOrder(16)]
public bool Instant { get; init; }
protected override BaseSpawner CreateEmpty() => new ProximitySpawner();
public override BaseSpawner ToSpawner()
{
var spawner = (ProximitySpawner)base.ToSpawner();
try
{
if (SpawnBounds != default)
{
spawner.SpawnBounds = SpawnBounds;
}
spawner.TriggerRange = TriggerRange;
spawner.SpawnMessage = SpawnMessage;
spawner.InstantFlag = Instant;
return spawner;
}
catch
{
spawner.Delete();
throw;
}
}
}