//  main.swift
//  Swift-test

import Foundation

struct Vector2D {
    var x = 0.0
    var y = 0.0
}

func +(left: Vector2D, right: Vector2D) -> Vector2D {
    return Vector2D(x: left.x + right.x, y: left.y + right.y)
}

let v1 = Vector2D(x: 2.0, y: 3.0)
let v2 = Vector2D(x: 1.0, y: 5.0)
print(v1 + v2)  // Swift_test.Vector2D(x: 3.0, y: 8.0)

infix operator +* {
    associativity none
    precedence 160
}

func +*(left: Vector2D, right: Vector2D) -> Double {
    return left.x * right.x + left.y * right.y
}

print(v1 +* v2) // 17.0

// MARK: 实现方法
func randomInRange(range: Range<Int>) -> Int {
    let count = UInt32(range.endIndex - range.startIndex)
    return Int(arc4random_uniform(count)) + range.startIndex
}

// TODO: 测试是否有效
for _ in 0...100 {
    print(randomInRange(1...6))
}

import Foundation

func convertToKelvin( celsius: Double) -> Double {
    let AbsoluteZeroInCelsius = -273.15
    assert(celsius > AbsoluteZeroInCelsius, "输入的摄氏温度不能低于绝对零度。")
    return celsius - AbsoluteZeroInCelsius
}

let roomTemperature = convertToKelvin(27)
print(roomTemperature)  // 300.15

class ClassA: NSObject { }
class ClassB: NSObject { }

let obj1: NSObject = ClassA()
let obj2: NSObject = ClassB()

print(obj1.isKindOfClass(ClassA.self))    // true
print(obj2.isMemberOfClass(ClassA.self))  // false

class MyClass {
    var date: NSDate {
        willSet {
        print("即将将日期从 \(date) 设定至 \(newValue)")
        }
        didSet {
        print("已经将日期从 \(oldValue) 设定至 \(date)")
        }
    }
    init() {
    date = NSDate()
    }
}

let foo = MyClass()
foo.date = foo.date.dateByAddingTimeInterval(10086)

// 输出
// 即将将日期从 2015-07-16 16:01:49 +0000 设定至 2015-07-16 18:49:55 +0000
// 已经将日期从 2015-07-16 16:01:49 +0000 设定至 2015-07-16 18:49:55 +0000

//
//  CalculatorBrain.swift
//  Calculator
//
//  Created by Will Ge on 7/11/15.
//  Copyright © 2015 gewill.org. All rights reserved.
//

import Foundation

class CauculatorBrain
{
    // 定义一个枚举类型，来分类表示输入的：运算数、一元运算和二元运算
    enum Op {
        case Operand(Double)
        case UnaryOperation(String, Double -> Double)
        case BinaryOperation(String, (Double, Double) -> Double)
    }
    
    // 定义一个数组来储存所有输入
    var opStack = [Op]()
    
    // 定义已知运算符
    var knownOps = [String:Op]()
    
    // 初始化已知运算符
    init() {
        knownOps["+"] = Op.BinaryOperation("+", +)
        knownOps["−"] = Op.BinaryOperation("−") {$1 - $0}
        knownOps["×"] = Op.BinaryOperation("×", *)
        knownOps["÷"] = Op.BinaryOperation("÷") {$1 / $0}
        knownOps["√"] = Op.UnaryOperation("√", sqrt)
    }
    
    // 定义一个函数，把输入递归取出
    func evaluate(ops: [Op]) -> (result: Double?, remainingOps:[Op]) {
        if !ops.isEmpty {
            var remainingOps = ops
            let op = remainingOps.removeLast()
            switch op {
            case.Operand(let operand):
                return (operand, remainingOps)
            case .UnaryOperation(_, let operation):
                let operandEvaluation = evaluate(remainingOps)
                if let operand = operandEvaluation.result {
                    return (operation(operand), operandEvaluation.remainingOps)
                }
            case .BinaryOperation(_, let operation):
                let op1Evaluation = evaluate(remainingOps)
                if let operand1 = op1Evaluation.result {
                    let op2Evaluation = evaluate(remainingOps)
                    if let operand2 = op2Evaluation.result {
                        return (operation(operand1, operand2), op2Evaluation.remainingOps)
                    }

                    
                }
                
            }
        }
        return (nil, ops)
    }
    
    func evaluate() -> Double? {
        let (result, remainder) = evaluate(opStack)
        print("\(opStack) = \(result) with \(remainder) left over")
        return result
        
    }
    
    // 运算数
    func pushOperand(operand: Double) -> Double? {
        opStack.append(Op.Operand(operand))
        return evaluate()
    }
    
    // 运算符
    func performOperation(symbol: String) -> Double? {
        if let operation = knownOps[symbol] {
            opStack.append(operation)
        }
        return evaluate()
    }
}

//
//  ViewController.swift
//  Calculator
//
//  Created by Will Ge on 6/28/15.
//  Copyright © 2015 gewill.org. All rights reserved.
//

import UIKit

class ViewController: UIViewController {
    

    @IBOutlet weak var history: UILabel!
    
    @IBOutlet weak var display: UILabel!
    
    
    var userIsInTheMiddleOfTypingANumber: Bool = false
    
    var brain = CauculatorBrain()

    @IBAction func appendDigit(sender: UIButton) {
        let digit = sender.currentTitle!
        if userIsInTheMiddleOfTypingANumber{
              display.text = display.text! + digit
        } else {
            display.text = digit
            userIsInTheMiddleOfTypingANumber = true
        }
    
        print("digit = \(digit)")
    }

    
    
    @IBAction func enter() {
        userIsInTheMiddleOfTypingANumber = false
        if let result = brain.pushOperand(displayValue) {
            displayValue = result
        } else {
            displayValue = 0
        }
        print("pushOperand = \(displayValue)")
        
    }
    
    @IBAction func operate(sender: UIButton) {
        
        if userIsInTheMiddleOfTypingANumber {
            enter()
        }
        if let operation = sender.currentTitle {
            print("\(operation)")
        }
    }
    

    
    var displayValue: Double{
        get {
            return NSNumberFormatter().numberFromString(display.text!)!.doubleValue
        }
        set {
            display.text = "\(newValue)"
            userIsInTheMiddleOfTypingANumber = false
        }
    }
}

//
//  ViewController.swift
//  Calculator
//
//  Created by Will Ge on 6/28/15.
//  Copyright © 2015 gewill.org. All rights reserved.
//

import UIKit

class ViewController: UIViewController {
    

    @IBOutlet weak var display: UILabel!
    
    var userIsInTheMiddleOfTypingANumber: Bool = false

    @IBAction func appendDigit(sender: UIButton) {
        let digit = sender.currentTitle!
        if userIsInTheMiddleOfTypingANumber{
              display.text = display.text! + digit
        } else {
            display.text = digit
            userIsInTheMiddleOfTypingANumber = true
        }
    
        print("digit = \(digit)")
    }

    var operandStack = Array<Double>()
    
    @IBAction func enter() {
        userIsInTheMiddleOfTypingANumber = false
        operandStack.append(displayValue)
        print("operandStack = \(operandStack)")
        
    }
    
    @IBAction func operate(sender: UIButton) {
        let operation = sender.currentTitle!
        if userIsInTheMiddleOfTypingANumber {
            enter()
        }
        switch operation {
        case "×": performOperation { $0 * $1 }
        case "÷": performOperation { $1 / $1 }
        case "+": performOperation { $0 + $1 }
        case "−": performOperation { $1 - $0 }
        case "√": performOperation1 { sqrt($0) }
        default: break
        }
    }
    
    func performOperation(operation: (Double, Double) ->Double) {
        if operandStack.count >= 2 {
            displayValue = operation(operandStack.removeLast(), operandStack.removeLast())
            enter()
        }
    }
    
    func performOperation1(operation: Double ->Double) {
        if operandStack.count >= 2 {
            displayValue = operation(operandStack.removeLast())
            enter()
        }
    }

    
    var displayValue: Double{
        get {
            return NSNumberFormatter().numberFromString(display.text!)!.doubleValue
        }
        set {
            display.text = "\(newValue)"
            userIsInTheMiddleOfTypingANumber = false
        }
    }
}

//  ViewController.swift


import UIKit

class ViewController: UIViewController {

    
    @IBOutlet weak var display: UILabel!
    
    var userIsInTheMiddleOfTypingANumber: Bool = false

    @IBAction func appendDigit(sender: UIButton) {
        let digit = sender.currentTitle!
        if userIsInTheMiddleOfTypingANumber{
              display.text = display.text! + digit
        } else {
            display.text = digit
            userIsInTheMiddleOfTypingANumber = true
        }
    
        print("digit = \(digit)")
    }

}