Daily Programmer X Mas Lights, using as many computed properties as possible

dailyProgrammerXmasLights.swift

import Foundation

///the led information
struct LED{
    let voltageDrop     :Float!
    let currentDrawn    :Float!
    let image           :String = "-|>|-"
    
    init(voltageDrop: Float, currentDrawn: Float){
        self.voltageDrop = voltageDrop
        self.currentDrawn = currentDrawn
    }
}

///the battery information
struct battery{
    var voltage         :Float!
    var capacityMAH     :Float!
    
    init(voltage: Float, capacity: Float){
        self.voltage     = voltage
        self.capacityMAH = capacity
    }
}

class circuit{
    
    var maximumNumberOfComponentsInSeries: Int {
        get{
            return Int(powerSupply.voltage/components.voltageDrop)
        }
    }
    
    var currentDrawOfComponentsInSeries: Float {
        get{
            return components.currentDrawn
        }
    }
    
    var powerSupply: battery
    var components: LED
    
    var numberOfHoursToRun: Int = 0
    
    var currentAvailableFromCell: Float{
        get{
            return powerSupply.capacityMAH / Float(numberOfHoursToRun)
        }
    }
    
    var maxParallelComponents: Int{
        get{
            return Int(currentAvailableFromCell/currentDrawOfComponentsInSeries)
        }
    }
    
    var totalComponents:Int{
        get{
            return maxParallelComponents * maximumNumberOfComponentsInSeries
        }
    }
    
    var remainingVoltage: Float{
        get{
            return powerSupply.voltage - (Float(maximumNumberOfComponentsInSeries) * components.voltageDrop)
        }
    }
    
    var resistorValueNeeded: Float{
        get{
            ///v = I*R, therefore r = V/I
            return remainingVoltage/(powerSupply.capacityMAH / Float(numberOfHoursToRun))
        }
    }
    
    
    init(components: LED, psuType: battery, hoursToRun: Int = 1){
        self.powerSupply = psuType
        self.components = components
        self.numberOfHoursToRun = hoursToRun
    }
    
    func draw(){
        
        ///show resistor value to 3dp
        print("Resistor Value: \(String(format: "%.3f",resistorValueNeeded))Ω")

        ///Need to have double the number of rows, so hat I can draw separators between the parallel branches
        for row in 1...(maxParallelComponents*2){
            
            ///The first row has the cell terminals on
            if row == 1{
                print("*", terminator: "")
            }
            ///if not the first row then there must be whitespace as padding to make everything line up
            else{
                print(" ", terminator: "")
            }
            
            ///There need to draw components on the separatos branches
            if row % 2 == 1{
                for comp in 1...(maximumNumberOfComponentsInSeries){
                    
                    ///Put an extra spcaes in front of each LED image
                    print("-\(components.image)", terminator: "")
                    
                    ///if it's the last time round then add an end spacer to line everything up
                    if comp == maximumNumberOfComponentsInSeries{
                        print("-", terminator: "")
                    }
                }
            }
            
                ///now the brnaches separators remain, I only want to print on the ones between the branches, 
                ///so miss out the last one
            else if row != (maxParallelComponents*2){
                ///draw connection
                print("|",  terminator: "")
                
                ///skip over the number of whitespaces where components would be
                for _ in 0...(maximumNumberOfComponentsInSeries){
                    for _ in 1...components.image.characters.count{
                        print(" ", terminator: "")
                    }
                }
                
                ///conneciton at end
                print("|",  terminator: "")
            }
            
            ///cell terminal
            if row == 1{
                print("-*", terminator: "")
            }
            
            ///go to next line
            print("")
            
        }
    }

}


var c = circuit(components: LED(voltageDrop: 1.7, currentDrawn: 0.02), psuType: battery(voltage: 9, capacity: 1.2), hoursToRun: 20)

c.draw()