feat: Adds attic ventilation calculation.

Sources/Routes/Models/AtticVentilation.swift

@@ -0,0 +1,102 @@
+public enum AtticVentilation {
+
+  public struct Request: Codable, Equatable, Sendable {
+
+    public let pressureDifferential: Double
+    public let outdoorTemperature: Double
+    public let outdoorDewpoint: Double
+    public let atticTemperature: Double
+    public let atticDewpoint: Double
+    public let atticFloorArea: Double
+    public let existingIntakeArea: Double?
+    public let existingExhaustArea: Double?
+
+    public init(
+      pressureDifferential: Double,
+      outdoorTemperature: Double,
+      outdoorDewpoint: Double,
+      atticTemperature: Double,
+      atticDewpoint: Double,
+      atticFloorArea: Double,
+      existingIntakeArea: Double? = nil,
+      existingExhaustArea: Double? = nil
+    ) {
+      self.pressureDifferential = pressureDifferential
+      self.outdoorTemperature = outdoorTemperature
+      self.outdoorDewpoint = outdoorDewpoint
+      self.atticTemperature = atticTemperature
+      self.atticDewpoint = atticDewpoint
+      self.atticFloorArea = atticFloorArea
+      self.existingIntakeArea = existingIntakeArea
+      self.existingExhaustArea = existingExhaustArea
+    }
+  }
+
+  public struct Response: Codable, Equatable, Sendable {
+
+    public let pressureDifferential: Double
+    public let temperatureDifferential: Double
+    public let dewpointDifferential: Double
+    public let stackEffect: Double
+    public let requiredVentilationArea: RequiredVentilationArea
+    public let recommendations: [String]
+    public let warnings: [String]
+    public let ventilationStatus: VentilationStatus
+
+    public init(
+      pressureDifferential: Double,
+      temperatureDifferential: Double,
+      dewpointDifferential: Double,
+      stackEffect: Double,
+      requiredVentilationArea: AtticVentilation.RequiredVentilationArea,
+      recommendations: [String],
+      warnings: [String],
+      ventilationStatus: AtticVentilation.VentilationStatus
+    ) {
+      self.pressureDifferential = pressureDifferential
+      self.temperatureDifferential = temperatureDifferential
+      self.dewpointDifferential = dewpointDifferential
+      self.stackEffect = stackEffect
+      self.requiredVentilationArea = requiredVentilationArea
+      self.recommendations = recommendations
+      self.warnings = warnings
+      self.ventilationStatus = ventilationStatus
+    }
+  }
+
+  public enum VentilationStatus: String, Codable, CaseIterable, Equatable, Sendable {
+    case adequate
+    case inadequate
+    case critical
+  }
+
+  public struct RequiredVentilationArea: Codable, Equatable, Sendable {
+
+    public let intake: Double
+    public let exhaust: Double
+
+    public init(intake: Double, exhaust: Double) {
+      self.intake = intake
+      self.exhaust = exhaust
+    }
+  }
+}
+
+#if DEBUG
+  public extension AtticVentilation.Response {
+    static let mock = Self(
+      pressureDifferential: 4,
+      temperatureDifferential: 15,
+      dewpointDifferential: 10,
+      stackEffect: 2,
+      requiredVentilationArea: .init(intake: 4.9, exhaust: 3.3),
+      recommendations: [
+        "Install 4.9 sq. ft. of intake ventilation",
+        "Install 3.3 sq. ft. of exhaust ventilation",
+        "Consider adding exhaust ventilation to balance pressure"
+      ],
+      warnings: ["High pressure differential - may indicate blocked vents or insufficient ventilation."],
+      ventilationStatus: AtticVentilation.VentilationStatus.allCases.randomElement()!
+    )
+  }
+#endif

Sources/Routes/SiteRoutes.swift

@@ -23,6 +23,7 @@ public extension SiteRoute {
 
   enum Api: Equatable, Sendable {
 
+    case calculateAtticVentilation(AtticVentilation.Request)
     case calculateCapacitor(Capacitor.Request)
     case calculateDehumidifierSize(DehumidifierSize.Request)
     case calculateHVACSystemPerformance(HVACSystemPerformance.Request)
@@ -32,6 +33,11 @@ public extension SiteRoute {
     static let rootPath = Path { "api"; "v1" }
 
     public static let router = OneOf {
+      Route(.case(Self.calculateAtticVentilation)) {
+        Path { "api"; "v1"; "calculateAtticPressure" }
+        Method.post
+        Body(.json(AtticVentilation.Request.self))
+      }
       Route(.case(Self.calculateCapacitor)) {
         Path { "api"; "v1"; "calculateRoomPressure" }
         Method.post
@@ -75,6 +81,7 @@ public extension SiteRoute {
   enum View: Equatable, Sendable {
 
     case index
+    case atticVentilation(AtticVentilation)
     case capacitor(Capacitor)
     case dehumidifierSize(DehumidifierSize)
     case hvacSystemPerformance(HVACSystemPerformance)
@@ -85,6 +92,9 @@ public extension SiteRoute {
       Route(.case(Self.index)) {
         Method.get
       }
+      Route(.case(Self.atticVentilation)) {
+        AtticVentilation.router
+      }
       Route(.case(Self.capacitor)) {
         Capacitor.router
       }
@@ -102,6 +112,37 @@ public extension SiteRoute {
       }
     }
 
+    public enum AtticVentilation: Equatable, Sendable {
+      case index
+      case submit(Routes.AtticVentilation.Request)
+
+      static let rootPath = "attic-ventilation"
+
+      public static let router = OneOf {
+        Route(.case(Self.index)) {
+          Path { rootPath }
+          Method.get
+        }
+        Route(.case(Self.submit)) {
+          Path { rootPath }
+          Method.post
+          Body {
+            FormData {
+              Field("pressureDifferential") { Double.parser() }
+              Field("outdoorTemperature") { Double.parser() }
+              Field("outdoorDewpoint") { Double.parser() }
+              Field("atticTemperature") { Double.parser() }
+              Field("atticDewpoint") { Double.parser() }
+              Field("atticFloorArea") { Double.parser() }
+              Optionally { Field("existingIntakeArea") { Double.parser() } }
+              Optionally { Field("existingExhaustArea") { Double.parser() } }
+            }
+            .map(.memberwise(Routes.AtticVentilation.Request.init))
+          }
+        }
+      }
+    }
+
     public enum Capacitor: Equatable, Sendable {
       case index(mode: Routes.Capacitor.Mode? = nil)
       case submit(Routes.Capacitor.Request)

Sources/Routes/String+double.swift

@@ -0,0 +1,17 @@
+import Foundation
+
+private let numberFormatter: NumberFormatter = {
+  let formatter = NumberFormatter()
+  formatter.numberStyle = .decimal
+  formatter.maximumFractionDigits = 2
+  return formatter
+}()
+
+public extension String.StringInterpolation {
+  mutating func appendInterpolation(double: Double, fractionDigits: Int = 2) {
+    let formatter = NumberFormatter()
+    formatter.numberStyle = .decimal
+    formatter.maximumFractionDigits = fractionDigits
+    appendInterpolation(numberFormatter.string(from: NSNumber(value: double))!)
+  }
+}