import scala.annotation.tailrec


object td3 extends App {
    val nbOfStudents = 150
    val nbOfMark = 5

    val r = scala.util.Random


    val names = List("Martin", "Bernard", "Dubois", "Thomas", "Robert", "Richard", "Petit", "Durand", "Leroy", "Moreau", "Simon", "Laurent", "Lefebvre", "Michel", "Garcia", "David", "Bertrand", "Roux", "Vincent", "Fournier", "Morel", "Girard", "Andre", "Lefevre", "Mercier", "Dupont", "Lambert", "Bonnet", "Francois", "Martinez", "Garnier", "Faure", "Rousseau", "Blanc", "Guerin", "Muller", "Henry", "Roussel", "Nicolas", "Perrin", "Morin", "Mathieu", "Clement", "Gauthier", "Dumont", "Lopez", "Fontaine", "Chevalier", "Robin", "Masson", "Sanchez", "Gerard", "Nguyen", "Boyer", "Denis", "Lemaire", "Duval", "Joly", "Gautier")

    val firstnames = List("Adam", "Alex", "Alexandre", "Alexis", "Anthony", "Antoine", "Benjamin", "Cédric", "Charles", "Christopher", "David", "Dylan", "Édouard", "Elliot", "Émile", "Étienne", "Félix", "Gabriel", "Guillaume", "Hugo", "Isaac", "Jacob", "Jérémy", "Jonathan", "Julien", "Justin", "Léo", "Logan", "Loïc", "Louis", "Lucas", "Ludovic", "Malik", "Mathieu", "Mathis", "Maxime", "Michaël", "Nathan", "Nicolas", "Noah", "Olivier", "Philippe", "Raphaël", "Samuel", "Simon", "Thomas", "Tommy", "Tristan", "Victor", "Vincent")

    /* From a list of name and first name generate a tuple which represent a student
    scala>studentGenerator(names,firstnames)
    res0: (String, String) = (Vincent,Ludovic)
   */
    def studentGenerator(names: List[String], firstNames: List[String]): (String, String) = (names(r.nextInt(names.size)),firstnames(r.nextInt(firstnames.size)))

    /*
    theStudents : a list of nbOfStudents of Students
   */
    lazy val theStudents: List[(String, String)] = List.fill(nbOfStudents)(studentGenerator(names,firstnames))

    /*
    marksGenerator : generates a list of mark, with a maximum nbOfMarks of mark
   */
    def marksGenerator(nbOfMarks: Int): List[Double] = List.fill(r.nextInt(nbOfMark)+1)(r.nextDouble()*20)

    /*
    marksForClass : generates a list of Students with marks
   */
    def marksForClass(nb: Int, aClass: List[(String, String)]): List[((String, String), List[Double])] = aClass.map(x => (x,marksGenerator(nb)))

    /*
    theClassMark : the list of the same students than theStudent with marks
   */
    lazy val theClassMark: List[((String, String), List[Double])] = marksForClass(nbOfMark,theStudents)

    /*
    average : From a list of mark, generates the average
   */
    def average(marks: List[Double]): Double = marks.sum / marks.size

    /*
    averageClass : from a list of students (with marks) generates the average marks for each students (for those who have mark)
   */
    def averageClass(aClass: List[((String, String), List[Double])]): List[((String, String), Double)] = aClass.map{case (x,y) => (x,average(y))}

    lazy val theClassResult = averageClass(theClassMark)

    /*
    betterStudent : which student is better than the other
   */
    def betterStudent(aStudent: ((String, String), Double), anotherStudent: ((String, String), Double)): ((String, String), Double) = if(aStudent._2 > anotherStudent._2) aStudent else anotherStudent

    /*
    worstStudent : which student is better than the other
   */
    def worstStudent(aStudent: ((String, String), Double), anotherStudent: ((String, String), Double)): ((String, String), Double) = if(aStudent._2 < anotherStudent._2) aStudent else anotherStudent

    /*
    theBestStudent is the student which has the highest average mark.
   */
    lazy val theBestStudent = theClassResult.reduce(betterStudent)

    /*
    theWorstStudent is the student which has the highest average mark.
   */
    lazy val theWorstStudent = theClassResult.reduce(worstStudent)


    /*
    qualifiedStudents are all students that have an average gretter (or equal) to 10
   */
    lazy val qualifiedStudents = theClassResult.filter(_._2 >= 10)

    /*
    prettyrPrintResult : a pretty printer for final result of a student
   */
    def prettyrPrintResult(aStudent: ((String, String), Double)): Unit = println(s"${aStudent._1._2} ${aStudent._1._1} : ${aStudent._2}")

    /*
    pretty print the class results, the qualified students and the best one !
   */
    def printInformations(): Unit = {
        println("----------    La classe :    ----------")
        theClassResult.foreach(prettyrPrintResult)
        println()
        println("----------    Ceux qui passent :    ----------")
        qualifiedStudents.foreach(prettyrPrintResult)
        println()
        println("----------    Le meilleur :    ----------")
        prettyrPrintResult(theBestStudent)
        println()
        println("----------    Thomas Lavaud :    ----------")
        prettyrPrintResult(theWorstStudent)
    }

    // remove comments after to print
    printInformations()

}