Appraisal

Appraisal.swift

typealias Amount = Float
struct User {
    let name: String
    let salary: Amount
}

enum PerformanceRating {
    enum Result {
        case warning(letter: String)
        case bonus(amount: Amount)
    }
    case superExceptional
    case exceptional
    case exceedExpection
    case meetExpection
    case partlyMeetExpection
    case needImprovement

    var bonusPercentage: Float {
        switch self {
        case .superExceptional:
            return 2
        case .exceptional:
            return 1.5
        case .exceedExpection:
            return 1
        case .meetExpection:
            return 0.5
        case .partlyMeetExpection, .needImprovement:
            return 0
        }
    }

    func giveResult(user: User) -> Result {
        switch self {
        case .superExceptional, .exceptional, .exceedExpection, .meetExpection:
            return Result.bonus(amount: bonusPercentage * user.salary)
        case .partlyMeetExpection:
            return Result.warning(letter: "Partly Meet expectation")
        case .needImprovement:
            return Result.warning(letter: "Need Improvement")
        }
    }
}

struct Appraisal {
    let user: User
    let rating: PerformanceRating

    func perform() -> PerformanceRating.Result {
        return rating.giveResult(user: user)
    }
}