import Elementary
import ElementaryHTMX
import PsychrometricClient
import Routes
import Styleguide

struct HVACSystemPerformanceForm: HTML, Sendable {

  let response: HVACSystemPerformance.Response?

  init(response: HVACSystemPerformance.Response? = nil) {
    self.response = response
  }

  var content: some HTML {
    FormHeader(label: "HVAC System Performance", svg: .thermometerSun)
    form(
      // Using index to get the correct path, but really uses the `submit` end-point.
      .hx.post(route: .hvacSystemPerformance(.index)),
      .hx.target("#result")
    ) {
      div(.class("space-y-6")) {
        div(.class("grid grid-cols-1 md:grid-cols-3 gap-4")) {
          LabeledContent(label: "System Size (Tons)") {
            Input(id: "systemSize", placeholder: "System size")
              .attributes(.type(.number), .min("1"), .step("0.5"), .autofocus, .required)
          }
          LabeledContent(label: "Airflow (CFM)") {
            Input(id: "airflow", placeholder: "Airflow")
              .attributes(.type(.number), .min("1"), .step("0.5"), .required)
          }
          LabeledContent(label: "Altitude (ft.)") {
            Input(id: "altitude", placeholder: "Project altitude (Optional)")
              .attributes(.type(.number), .min("1"), .step("0.5"))
          }
        }

        div(.class("grid grid-cols-1 md:grid-cols-2 gap-8")) {
          div(.class("space-y-4")) {
            h3(.class("text-lg font-medium")) { "Return Air" }
            LabeledContent(label: "Dry Bulb (°F)") {
              Input(id: "returnAirTemperature", placeholder: "Return temperature")
            }
            LabeledContent(label: "Indoor Humdity (%)") {
              Input(id: "returnAirHumidity", placeholder: "Return humidity")
                .attributes(.type(.number), .step("0.1"), .min("0.1"), .required)
            }
          }
          div(.class("space-y-4")) {
            h3(.class("text-lg font-medium")) { "Supply Air" }
            LabeledContent(label: "Dry Bulb (°F)") {
              Input(id: "supplyAirTemperature", placeholder: "Supply temperature")
            }
            LabeledContent(label: "Indoor Humdity (%)") {
              Input(id: "supplyAirHumidity", placeholder: "Supply humidity")
                .attributes(.type(.number), .step("0.1"), .min("0.1"), .required)
            }
          }
        }
        div {
          SubmitButton(label: "Calculate Performance")
        }
      }
    }
    div(.id("result")) {
      if let response {
        HVACSystemPerformanceResult(response: response)
      }
    }
  }
}

struct HVACSystemPerformanceResult: HTML, Sendable {
  let response: HVACSystemPerformance.Response

  var content: some HTML {
    ResultContainer(reset: .hvacSystemPerformance(.index)) {
      // ResultContainer {
      // Capacities
      div(.class("grid grid-cols-1 lg:grid-cols-3 gap-4")) {
        CapacityContainer(title: "Total Capacity", capacity: response.capacity.total, shr: nil)
          .attributes(.class("text-blue-600 bg-blue-100 border border-blue-600 p-6"))

        CapacityContainer(title: "Sensible Capacity", capacity: response.capacity.sensible, shr: response.capacity.shr)
          .attributes(.class("text-green-600 bg-green-100 border border-green-600 p-6"))

        CapacityContainer(title: "Latent Capacity", capacity: response.capacity.latent, shr: nil)
          .attributes(.class("text-purple-600 bg-purple-100 border border-purple-600 p-6"))
      }

      // System Metrics
      SystemMetricsView(metrics: response.systemMetrics, shr: response.capacity.shr)
        .attributes(.class("mt-8 border rounded-xl shadow-lg"))

      // Psychrometric properties.
      div(.class("grid grid-cols-1 md:grid-cols-2 gap-6 mt-8")) {
        PsychrometricPropertiesGrid(title: "Return Air Properties", properties: response.returnAirProperties)
        PsychrometricPropertiesGrid(title: "Supply Air Properties", properties: response.supplyAirProperties)
      }
    }
  }

  private struct CapacityContainer: HTML, Sendable {
    let title: String
    let capacity: Double
    let shr: Double?

    var tons: Double { capacity / 12000 }

    var content: some HTML<HTMLTag.div> {
      div(.class("rounded-xl")) {
        h4(.class("text-lg font-semibold mb-2")) { title }
        div(.class("text-3xl font-bold")) {
          "\(double: tons, fractionDigits: 1)"
          span(.class("text-xl ps-2")) { "Tons" }
        }
        div(.class("text-sm mt-1")) {
          "\(double: capacity, fractionDigits: 1) BTU/h"
        }
      }
    }
  }

  private struct SystemMetricsView: HTML, Sendable {
    let metrics: HVACSystemPerformance.SystemMetrics
    let shr: Double

    var content: some HTML<HTMLTag.div> {
      div {
        h4(.class("""
        text-lg font-semibold flex justify-center py-2 mb-4 text-blue-600 dark:text-slate-300
        """)) { "System Performance Metrics" }

        div(.class("flex justify-between items-center p-4")) {
          div(.class("space-y-3")) {
            LabeledMetric(label: "Airflow per Ton", value: metrics.cfmPerTon, units: "CFM/ton")
              .attributes(.class("mb-8"))

            div {
              LabeledMetric(label: "Temperature Split", value: metrics.actualTemperatureSplit, units: "°F")
              p(.class("text-xs")) {
                "Target: \(double: metrics.targetTemperatureSplit) °F"
              }
            }
          }
          div(.class("space-y-3")) {
            LabeledMetric(label: "Moisture Removal", value: metrics.condensationRateGallonsPerHour, units: "gal/h")
              .attributes(.class("mb-8"))
            LabeledMetric(label: "Sensible Heat Ratio", value: shr, units: "%")
          }
        }

        if shr < 0.7 {
          WarningBox("Low sensible heat ratio may indicate excessive dehumidification or low airflow.")
            .attributes(.class("mb-4 mx-8"))
        }
      }
    }

    private struct LabeledMetric: HTML, Sendable {
      let label: String
      let value: Double
      let units: String
      let fractionDigits: Int

      init(
        label: String,
        value: Double,
        units: String,
        fractionDigits: Int = 1
      ) {
        self.label = label
        self.value = value
        self.units = units
        self.fractionDigits = fractionDigits
      }

      var content: some HTML<HTMLTag.div> {
        div {
          span(.class("text-sm")) { label }
          p(.class("text-2xl font-semibold")) {
            "\(double: value, fractionDigits: fractionDigits)"
            span(.class("text-base font-normal ps-2")) { units }
          }
        }
      }
    }

  }

  private struct PsychrometricPropertiesGrid: HTML, Sendable {
    let title: String
    let properties: PsychrometricProperties

    var content: some HTML<HTMLTag.div> {
      div(.class("rounded-xl border border-blue-600 dark:border-gray-400 bg-blue-100 dark:bg-slate-700 p-4")) {
        h4(.class("""
          text-lg font-semibold flex justify-center py-2 mb-4 text-blue-600 dark:text-slate-300
        """)) { title }
        PsychrometricPropertiesView(properties: properties)
          .attributes(.class("grid grid-cols-1 gap-4"))
      }
    }
  }
}