Merge branch 'phase/84-wet-aftereffect'

src/HSchool.Simulation/DiseaseSystem.cs

@@ -37,6 +37,7 @@ internal static class DiseaseSystem
         if (school.LastDiseaseDay != dayNumber)
         {
             school.LastDiseaseDay = dayNumber;
+            changed |= TryWet(school);
             changed |= TryOnset(school);
             changed |= TryContagion(school);
         }
@@ -58,6 +59,70 @@ internal static class DiseaseSystem
         return changed;
     }
 
+    private static bool TryWet(School school)
+    {
+        var catalog = school.Catalog!;
+        var rules = catalog.BehaviorRules;
+        if (rules is null || !catalog.Diseases.ContainsKey(DiseaseFamilies.WetDefName))
+        {
+            return false;
+        }
+
+        var chance = school.Weather.Precipitation switch
+        {
+            Precipitation.Rain => rules.WetRainChance,
+            Precipitation.Snow => rules.WetSnowChance,
+            _ => 0f,
+        };
+        if (chance <= 0f)
+        {
+            return false;
+        }
+
+        var dayNumber = DateOnly.FromDateTime(school.Clock.Time).DayNumber;
+        var source = school.Weather.Precipitation == Precipitation.Snow ? "snow" : "rain";
+        var changed = false;
+
+        foreach (var person in school.Roster!.People)
+        {
+            if (!person.IsStudent && !person.IsStaff)
+            {
+                continue;
+            }
+
+            if (school.Plans.TryGetValue(person.Id, out var plan) && !plan.Comes)
+            {
+                continue;
+            }
+
+            if (HealthConditions.Has(person, DiseaseFamilies.WetDefName))
+            {
+                continue;
+            }
+
+            var roll = Seed.Mix(school.PeopleSeed, person.Id, dayNumber, Seed.WetSalt);
+            var unit = (roll & int.MaxValue) / (float)int.MaxValue;
+            if (unit >= chance)
+            {
+                continue;
+            }
+
+            HealthConditions.Add(
+                person,
+                new HealthCondition
+                {
+                    DefName = DiseaseFamilies.WetDefName,
+                    Severity = 0.65f,
+                    Progress = 0f,
+                    Source = source,
+                    StartedAt = school.Clock.Time,
+                });
+            changed = true;
+        }
+
+        return changed;
+    }
+
     private static bool TryOnset(School school)
     {
         var catalog = school.Catalog!;
@@ -78,16 +143,19 @@ internal static class DiseaseSystem
                 continue;
             }
 
+            var wet = HealthConditions.Has(person, DiseaseFamilies.WetDefName);
+
             foreach (var disease in catalog.Diseases.Values)
             {
                 if (disease.Abstract
+                    || disease.Family.Equals(DiseaseFamilies.Condition, StringComparison.Ordinal)
                     || HealthConditions.Has(person, disease.DefName)
                     || DiseaseImmunities.IsImmune(person, disease.DefName, school.Clock.Time))
                 {
                     continue;
                 }
 
-                var chance = OnsetChance(disease, weather, rules.DiseaseVectorScale);
+                var chance = OnsetChance(disease, weather, rules.DiseaseVectorScale, wet);
                 if (chance <= 0f)
                 {
                     continue;
@@ -108,7 +176,7 @@ internal static class DiseaseSystem
                         DefName = disease.DefName,
                         Severity = 0.05f,
                         Progress = 0f,
-                        Source = SourceOf(disease, weather),
+                        Source = SourceOf(disease, weather, wet),
                         StartedAt = school.Clock.Time,
                     });
                 changed = true;
@@ -145,6 +213,7 @@ internal static class DiseaseSystem
             {
                 if (!catalog.Diseases.TryGetValue(condition.DefName, out var disease)
                     || disease.Abstract
+                    || disease.Family.Equals(DiseaseFamilies.Condition, StringComparison.Ordinal)
                     || !CanTransmit(condition, disease, now))
                 {
                     continue;
@@ -348,7 +417,11 @@ internal static class DiseaseSystem
         return map;
     }
 
-    internal static float OnsetChance(DiseaseDef disease, OutdoorWeather weather, float vectorScale)
+    internal static float OnsetChance(
+        DiseaseDef disease,
+        OutdoorWeather weather,
+        float vectorScale,
+        bool wet = false)
     {
         if (vectorScale <= 0f)
         {
@@ -368,11 +441,21 @@ internal static class DiseaseSystem
             _ => 0f,
         };
 
+        if (wet)
+        {
+            chance += disease.WetChancePerDay;
+        }
+
         return Math.Clamp(chance * vectorScale, 0f, 1f);
     }
 
-    private static string SourceOf(DiseaseDef disease, OutdoorWeather weather)
+    private static string SourceOf(DiseaseDef disease, OutdoorWeather weather, bool wet)
     {
+        if (wet && disease.WetChancePerDay > 0f)
+        {
+            return "wet";
+        }
+
         if (disease.ColdBelowC is { } below && weather.TemperatureC <= below)
         {
             return "cold";