/*
A pattern match includes a sequence of alternatives, each starting with the keyword case.
Each alternative includes a pattern and one or more expressions, which will be evaluated
if the pattern matches. An arrow symbol => separates the pattern from the expressions.
*/

def matchTest(x: Int): String = x match {
  case 1 => "one"
  case 2 => "two"
  case _ => "many"
}

matchTest(1)
matchTest(2)
matchTest(3)

def matchTest2(x: Any): Any = x match {
  case 1 => "one"
  case "two" => 2
  case y: Int => "scala.Int"
  case _ => "many"
}

matchTest2(1)
matchTest2("two")
matchTest2(3)





sealed class Account
case class Paypal(email:String) extends Account
case class Bitcoin(key:String) extends Account
case class User(name:String, account:Account)

def whatis1(obj: Any) = {
  if (obj.isInstanceOf[User]) {
    val user = obj.asInstanceOf[User]
    if (user.account.isInstanceOf[Paypal]) {
      val paypal = user.account.asInstanceOf[Paypal]
      "Paypal for email" + paypal.email
    }
    else if (user.account.isInstanceOf[Bitcoin]) {
      val bitcoin = user.account.asInstanceOf[Bitcoin]
      "Bitcoin with key " + bitcoin.key
    }
    else {
      "Unknown account type"
    }
  } else {
    "Unknown object type"
  }

}

def whatis2(obj:Any) = {
  obj match {
    case User(name, Paypal(email)) =>
      "Paypal for meail " + email
    case User(name, Bitcoin(email)) =>
      "Bitcoin for meail " + email
    case User(name, _) =>
      "Unknown account type"
    case _ => "Unknown object type"
  }
}

whatis1(User("bilbo", Paypal("bilbo@shire.com")))
whatis2(User("bilbo", Paypal("bilbo@shire.com")))

case class WellsFargo(name:String)  extends Account
whatis2(User("bilbo", WellsFargo("bilbo@shire.com")))
whatis2(WellsFargo("johnbush"))

def whatis3(obj: Any) = {
  if (obj.isInstanceOf[User]) {
    val user = obj.asInstanceOf[User]
    if (!user.name.isEmpty) {
      if (user.account.isInstanceOf[Paypal]) {
        val paypal = user.account.asInstanceOf[Paypal]
        if (paypal.equals("bilbo@shire.com"))
          "Bilbo's got Paypal"
      }
    }
  }
}

def whatis4(obj:Any) = {
  obj match {
    case User(name, Paypal("bilbo@shire.com"))
      if !name.isEmpty => "Bilbo's got Paypal"
  }
}

def getTuple: (User, Account) = (User("bilbo", Paypal("bilbo@shire.com")), Paypal("bilbo@shire.com"))
val u = getTuple._1
val a = getTuple._2
val (user, account) = getTuple


case class Dog(name:String)
case class Person(first:String, last:String)

def echoWhatYouGaveMe(x: Any): String = x match {

  // constant patterns
  case 0 => "zero"
  case true => "true"
  case "hello" => "you said 'hello'"
  case Nil => "an empty List"

  // sequence patterns
  case List(0, _, _) => "a three-element list with 0 as the first element"
  case List(1, _*) => "a list beginning with 1, having any number of elements"
  case Vector(1, _*) => "a vector starting with 1, having any number of elements"

  // tuples
  case (a, b) => s"got $a and $b"
  case (a, b, c) => s"got $a, $b, and $c"

  // constructor patterns
  case Person(first, "Alexander") => s"found an Alexander, first name = $first"
  case Dog("Suka") => "found a dog named Suka"

  // typed patterns
  case s: String => s"you gave me this string: $s"
  case i: Int => s"thanks for the int: $i"
  case f: Float => s"thanks for the float: $f"
  case a: Array[Int] => s"an array of int: ${a.mkString(",")}"
  case as: Array[String] => s"an array of strings: ${as.mkString(",")}"
  case d: Dog => s"dog: ${d.name}"
  case list: List[_] => s"thanks for the List: $list"
  case m: Map[_, _] => m.toString

  // the default wildcard pattern
  case _ => "Unknown"
}

// trigger the constant patterns
echoWhatYouGaveMe(0)
echoWhatYouGaveMe(true)
echoWhatYouGaveMe("hello")
echoWhatYouGaveMe(List())

// trigger the sequence patterns
echoWhatYouGaveMe(List(0,1,2))
echoWhatYouGaveMe(List(1,2))
echoWhatYouGaveMe(List(1,2,3))
echoWhatYouGaveMe(Vector(1,2,3))

// trigger the tuple patterns
echoWhatYouGaveMe((1,2))        // two element tuple
echoWhatYouGaveMe((1,2,3))      // three element tuple

// trigger the constructor patterns
echoWhatYouGaveMe(Person("Melissa", "Alexander"))
echoWhatYouGaveMe(Dog("Suka"))

// trigger the typed patterns
echoWhatYouGaveMe("Hello, world")
echoWhatYouGaveMe(42)
echoWhatYouGaveMe(42F)
echoWhatYouGaveMe(Array(1,2,3))
echoWhatYouGaveMe(Array("coffee", "apple pie"))
echoWhatYouGaveMe(Dog("Fido"))
echoWhatYouGaveMe(List("apple", "banana"))
echoWhatYouGaveMe(Map(1->"Al", 2->"Alexander"))

// trigger the wildcard pattern
echoWhatYouGaveMe("33d")