scala case test

package caseclass
//1.使用 case class 创建图书信息类 Book：包含四个属性：ID，书名，作者，价格，数量。
//2.创建一个名为 bookList 的可变 List，它只能用来保存 Book 的实例。
//3.初始化三本不同的书（注意 id 不同就是不同的书），加入到 bookList 中。
//4.添加一本已经存在的书。此时应该去修改 bookList 中对应书目的数量，而不是去添加一条新数据。
//5.根据图书名称查询是否在列表中（通过遍历列表对比名称）
//6.删除指定书名的书
//7.删除指定 ID 的书
//8.对于图书按价格从高到低排序。
//9.遍历图书列表，并打印每本书的详细信息
//10.计算全部总的金额

object case03 {

  case class Book(id: String, name: String, author: String, price: Double, amount: Int)

  object Case03 {
    def main(args: Array[String]): Unit = {

      val bookList = scala.collection.mutable.ListBuffer[Book]()


      val book1 = Book("1", "无羁", "墨香铜臭", 80.0, 10)
      val book2 = Book("2", "某某", "木苏里", 50.0, 9)
      val book3 = Book("3", "全球高考", "木苏里", 60.0, 5)
      bookList ++= List(book1, book2, book3)
      println("=== 初始化后的图书列表 ===")
      printBookList(bookList)


      println("\n=== 尝试添加已存在的书（ID=1，无羁）===")
      val existingBook = Book("1", "无羁", "墨香铜臭", 80.0, 3) 
      addBook(bookList, existingBook)
      println("添加后的图书列表：")
      printBookList(bookList)


      println("\n=== 查询图书：《某某》===")
      val targetName = "某某"
      val isExist = checkBookByName(bookList, targetName)
      println(s"图书《$targetName》是否存在：$isExist")

      println("=== 查询图书：《撒野》===")
      val targetName2 = "撒野"
      val isExist2 = checkBookByName(bookList, targetName2)
      println(s"图书《$targetName2》是否存在：$isExist2")


      println("\n=== 删除书名：《全球高考》===")
      deleteBookByName(bookList, "全球高考")
      println("删除后的图书列表：")
      printBookList(bookList)

      println("\n=== 删除 ID=2 的书 ===")
      deleteBookById(bookList, "2")
      println("删除后的图书列表：")
      printBookList(bookList)


      println("\n=== 按价格从高到低排序 ===")
      val sortedList = bookList.sortWith((a, b) => a.price > b.price) 
      printBookList(sortedList)




      println("\n=== 计算总金额 ===")
      val totalAmount = calculateTotalAmount(bookList)
      println(s"所有图书的总金额：$totalAmount 元")
    }


    def printBookList(books: scala.collection.mutable.ListBuffer[Book]): Unit = {
      if (books.isEmpty) {
        println("列表为空")
        return
      }
      books.foreach(book => {
        println(s"ID：${book.id} | 书名：${book.name} | 作者：${book.author} | 价格：${book.price}元 | 数量：${book.amount}本")
      })
    }


    def addBook(books: scala.collection.mutable.ListBuffer[Book], newBook: Book): Unit = {
      books.find(_.id == newBook.id) match {
        case Some(existBook) =>

          val updatedBook = existBook.copy(amount = existBook.amount + newBook.amount)
          books -= existBook
          books += updatedBook
          println(s"图书《${newBook.name}》已存在，数量更新为：${updatedBook.amount}本")
        case None =>

          books += newBook
          println(s"图书《${newBook.name}》新增成功")
      }
    }


    def checkBookByName(books: scala.collection.mutable.ListBuffer[Book], name: String): Boolean = {

      books.exists(book => book.name.equalsIgnoreCase(name))
    }


    def deleteBookByName(books: scala.collection.mutable.ListBuffer[Book], name: String): Unit = {
      val toDelete = books.filter(_.name.equalsIgnoreCase(name))
      if (toDelete.nonEmpty) {
        books --= toDelete
        println(s"成功删除 ${toDelete.size} 本同名图书：《$name》")
      } else {
        println(s"未找到书名《$name》的图书，删除失败")
      }
    }


    def deleteBookById(books: scala.collection.mutable.ListBuffer[Book], id: String): Unit = {
      books.find(_.id == id) match {
        case Some(book) =>
          books -= book
          println(s"成功删除 ID=$id 的图书：《${book.name}》")
        case None =>
          println(s"未找到 ID=$id 的图书，删除失败")
      }
    }


    def calculateTotalAmount(books: scala.collection.mutable.ListBuffer[Book]): Double = {

      books.map(book => book.price * book.amount).sum
    }
  }
}