Binary Search visualized on the Apple Watch, Swiftsy Bitsy Datastructures and Algorithms

BinarySearchView.swift

//
//  BinarySearchView.swift
//  WatchSort WatchKit Extension
//
//  Created by Paul Wood on 8/22/19.
//  Copyright © 2019 Paul Wood. All rights reserved.
//

import SwiftUI
import Combine

class BinarySearchAlgorithmDisplayable: ObservableObject {
  var displayResults: [[BinarySearchNode<Int>]]!
  let count: Int = 15
  var values: [BinarySearchNode<Int>] {
    return displayResults[currentIndex]
  }
  func displayNext() {
    guard !isSortedInternal else { return }
    objectWillChange.send()
    currentIndex += 1
    if currentIndex >= displayResults.count - 1 {
      isSortedInternal = true
    }
  }
  var isSorted: Bool {
    return isSortedInternal
  }
  private var currentIndex = 0
  private var isSortedInternal = false
  public var objectWillChange = PassthroughSubject<Void, Never>()
  private var search: Int = 1
  public var searching: Binding<Double>!
  
  init() {
    let b = Binding<Double>(
    get:{
      return Double(self.search)
    }, set: {
      self.objectWillChange.send()
      self.search = Int(round($0))
      self.resultsForTree(searching: Int(round($0)))
    })
    self.searching = b
    resultsForTree(searching: search)
  }
  
  func resultsForTree(searching: Int){
    currentIndex = 0
    isSortedInternal = false
    let tree = BinarySearchTree<Int>(value: 08)
    _ = ([04,12,02,06,10,14,01,03,05,07,09,11,13,15]).map { v in
      tree.insert(value: v)
    }
    displayResults = BinarySearchAlgorithmDisplayable.recordSearch(tree,
                                                                   value: searching)
  }
}

extension BinarySearchAlgorithmDisplayable {
  static func recordSearch<T>(_ tree: BinarySearchTree<T>,
                              value: T) -> [[BinarySearchNode<T>]] {
    var results = [[BinarySearchNode<T>]]()
    
    var node: BinarySearchTree? = tree
    
    func createRecord(tree: BinarySearchTree<T>,
                      currentNodeValue: T) -> [BinarySearchNode<T>] {
      var list = [BinarySearchNode<T>]()
      tree.traversePreOrder { value in
        list.append(BinarySearchNode<T>(index: 0,
                                        content: value,
                                        wasSearched: false,
                                        isSearched: value == currentNodeValue))
      }
      return list
    }
    
    
    while let n = node {
      results.append(createRecord(tree: tree, currentNodeValue: n.value))
      if value < n.value {
        node = n.left
      } else if value > n.value {
        node = n.right
      } else {
        break
        //return node
      }
    }
    
    return results
  }
}

struct BinarySearchNode<T: Comparable> {
  var index: Int
  var content: T
  var wasSearched: Bool
  var isSearched: Bool
}

struct BinarySearchView: View {
  
  @ObservedObject var bsAlgorithm = BinarySearchAlgorithmDisplayable()
  
  private func handleTap() {
    bsAlgorithm.displayNext()
  }
  @State var quantity: Double = 0

  var body: some View {
    VStack{
      HStack{
        IndexView(bsAlgorithm.values[0])
      }
      HStack{
        Spacer()
        IndexView(bsAlgorithm.values[1])
        Spacer()
        IndexView(bsAlgorithm.values[8])
        Spacer()
      }
      HStack{
        Spacer()
        IndexView(bsAlgorithm.values[2])
        Spacer()
        IndexView(bsAlgorithm.values[5])
        Spacer()
        IndexView(bsAlgorithm.values[9])
        Spacer()
        IndexView(bsAlgorithm.values[12])
        Spacer()
      }
      HStack(spacing:1){
        IndexView(bsAlgorithm.values[3])
        IndexView(bsAlgorithm.values[4])
        IndexView(bsAlgorithm.values[6])
        IndexView(bsAlgorithm.values[7])
        IndexView(bsAlgorithm.values[10])
        IndexView(bsAlgorithm.values[11])
        IndexView(bsAlgorithm.values[13])
        IndexView(bsAlgorithm.values[14])
      }
      Slider(value: bsAlgorithm.searching, in: ClosedRange(uncheckedBounds: (1,15)), step: 1)
      
      }.navigationBarTitle(      Text("Binary Search: \(Int(bsAlgorithm.searching.wrappedValue))"))
    .onTapGesture(perform: handleTap)
      .animation(.default)
  }
  
  private func IndexView(_ node: BinarySearchNode<Int>) -> some View {
    return Text(String(node.content))
      .frame(width: 18, height: 20, alignment: .center)
      .background(
        RoundedRectangle(cornerRadius: 1.0)
          .border(node.isSearched ? Color.green : Color.white, width: 1)
          .foregroundColor(Color.gray)
        
    )
  }
  
}

struct BinarySearchView_Previews: PreviewProvider {
  static var previews: some View {
    BinarySearchView()
  }
}