import CasePaths
import PsychrometricClient
@preconcurrency import URLRouting

public enum HydronicSystemPressure {

  public static let description = """
  Calculate the required hydronic system pressure based on height of a building.
  """

  public struct Request: Codable, Equatable, Hashable, Sendable {
    public let height: Double
    public let waterTemperature: Double?

    public init(height: Double, waterTemperature: Double? = nil) {
      self.height = height
      self.waterTemperature = waterTemperature
    }

    public enum FieldKey: String, CaseIterable {
      case height
      case waterTemperature
    }
  }

  public struct Response: Codable, Equatable, Sendable {

    public let pressure: Double
    public let waterDensity: DensityOf<Water>
    public let warnings: [String]

    public init(pressure: Double, waterDensity: DensityOf<Water>, warnings: [String]) {
      self.pressure = pressure
      self.waterDensity = waterDensity
      self.warnings = warnings
    }
  }
}

// MARK: - Router

public extension SiteRoute.View {

  enum HydronicSystemPressure: Equatable, Hashable, Sendable {
    case index
    case submit(Routes.HydronicSystemPressure.Request)

    typealias Key = Routes.HydronicSystemPressure.Request.FieldKey
    static let rootPath = "hydronic-system-pressure"

    public static let router = OneOf {
      Route(.case(Self.index)) {
        Path { rootPath }
        Method.get
      }
      Route(.case(Self.submit)) {
        Path { rootPath }
        Method.post
        Body {
          FormData {
            Field(Key.height) { Double.parser() }
            Optionally { Field(Key.waterTemperature) { Double.parser() } }
          }
          .map(.memberwise(Routes.HydronicSystemPressure.Request.init))
        }
      }
    }
  }

}

#if DEBUG
  public extension HydronicSystemPressure.Response {
    static let mock = Self(
      pressure: 15,
      waterDensity: 62.37,
      warnings: [
        "Water density based on 60 water - include water temperature for more accurate result."
      ]
    )
  }

#endif