import SwiftUI
import SFSafeSymbols

private let df: DateFormatter = {
    let df = DateFormatter()
    df.locale = .current
    df.dateStyle = .short
    df.timeStyle = .short
    return df
}()

struct DeviceInfoView: View {
    
    private let storageWarnBytes = 500
    
    let info: DeviceInfo
    
    private var runTimeString: String {
        let number = info.numberOfSecondsRunning
        guard number >= 60 else {
            return "\(number) seconds"
        }
        let minutes = number / 60
        guard minutes > 1 else {
            return "1 minute"
        }
        guard minutes >= 60 else {
            return "\(minutes) minutes"
        }
        let hours = minutes / 60
        guard hours > 1 else {
            return "1 hour"
        }
        guard hours >= 60 else {
            return "\(hours) hours"
        }
        let days = hours / 24
        guard days > 1 else {
            return "1 day"
        }
        return "\(days) days"
    }
    
    private var nextUpdateText: String {
        let secs = Int(info.nextMeasurement.timeIntervalSinceNow.rounded())
        guard secs > 1 else {
            return "Now"
        }
        return "In \(secs) seconds"
    }
    
    private var storageIcon: SFSymbol {
        if info.storageSize - info.numberOfRecordedBytes < storageWarnBytes {
            return .externaldriveTrianglebadgeExclamationmark
        }
        return .externaldrive
    }
    
    private var storageText: String {
        if info.storageSize <= 0 {
            return "\(info.numberOfRecordedBytes)"
        }
        return "\(info.numberOfRecordedBytes) / \(info.storageSize) Bytes (\(info.storageFillPercentage) %)"
    }
    
    func sensorView(_ sensor: TemperatureSensor?, id: Int) -> some View {
        VStack(alignment: .leading, spacing: 5) {
            Text("Sensor \(id)")
                .font(.headline)
            if let sensor {
                HStack {
                    Image(systemSymbol: sensor.temperatureIcon)
                        .frame(width: 30)
                    Text(sensor.temperatureText)
                }
                HStack {
                    Image(systemSymbol: .arrowTriangle2Circlepath)
                        .frame(width: 30)
                    Text(sensor.updateText)
                    Spacer()
                }
                HStack {
                    Image(systemSymbol: .tag)
                        .frame(width: 30)
                    Text(sensor.hexAddress)
                }
            } else {
                HStack {
                    Image(systemSymbol: .thermometerMediumSlash)
                        .frame(width: 30)
                    Text("Not connected")
                }
            }
            
        }
    }
    
    var body: some View {
        VStack(alignment: .leading, spacing: 5) {
            VStack(alignment: .leading, spacing: 5) {
                Text("Recording")
                    .font(.headline)
                HStack {
                    Image(systemSymbol: .power)
                        .frame(width: 30)
                    Text(df.string(from: info.deviceStartTime))
                    Spacer()
                }
                HStack {
                    Image(systemSymbol: .clock)
                        .frame(width: 30)
                    Text("\(runTimeString)")
                }
                HStack {
                    Image(systemSymbol: .stopwatch)
                        .frame(width: 30)
                    Text("Every \(info.measurementInterval) seconds")
                    Spacer()
                }
                HStack {
                    Image(systemSymbol: .arrowTriangle2Circlepath)
                        .frame(width: 30)
                    Text(nextUpdateText)
                    Spacer()
                }
            }
            VStack(alignment: .leading, spacing: 5) {
                Text("Storage")
                    .font(.headline)
                HStack {
                    Image(systemSymbol: .speedometer)
                        .frame(width: 30)
                    Text("\(info.numberOfMeasurements) Measurements")
                }
                HStack {
                    Image(systemSymbol: storageIcon)
                        .frame(width: 30)
                    Text(storageText)
                }
                HStack {
                    Image(systemSymbol: .iphoneAndArrowForward)
                        .frame(width: 30)
                    Text("\(info.transferBlockSize) Byte Block Size")
                }
            }
            sensorView(info.sensor0, id: 0)
            sensorView(info.sensor1, id: 1)
            Spacer()
            HStack {
                Spacer()
                Text("Updated \(info.receivedDate.timePassedText)")
                    .font(.footnote)
                    .textCase(.uppercase)
                Spacer()
            }
        }.padding()
    }
}

struct DeviceInfoView_Previews: PreviewProvider {
    static var previews: some View {
        DeviceInfoView(info: .mock)
            .previewLayout(.fixed(width: 375, height: 500))
    }
}