fsaar/TicTacToe

//
//  TTTTicTacToeView.swift
//  TicTacToe
//
//  Created by Frank Saar on 27/08/2016.
//  Copyright © 2016 SAMedialabs. All rights reserved.
//

import UIKit


@objc enum TTTBoardPlayer : Int {
    case machine
    case human
}

protocol TTTBoardDelegate : class {
    func evaluateBoardChange(_ board : TTTBoard,player : TTTBoardPlayer,config: TTTBoardConfig,position : TTTBoardPosition)
}

extension Selector {
    static let cellTouchHandler : Selector = #selector(TTTBoard.cellTouchHandler(_ :))
}


public class TTTBoard : UIView {
    weak var delegate : TTTBoardDelegate?
    @IBOutlet var cells : [TTTCell]!
    var config = TTTBoardConfig.empty() {
        didSet {
            config.states.enumerated().forEach { index,state in
                self.cells[index].state = state
            }
        }
    }
    
    override public func awakeFromNib() {
        super.awakeFromNib()
        self.clipsToBounds = true
        self.layer.borderColor = self.cells.first?.layer.borderColor
        setupCellPositions()
        setupTouchHandler() 
    }
    @objc func cellTouchHandler(_ recognizer : UITapGestureRecognizer) {
        if let cell = recognizer.view as? TTTCell , cell.state == .undefined {
            self.delegate?.evaluateBoardChange(self, player: .human, config: config, position: cell.position)
        }
    }
    
    func highlight(_ positions : [TTTBoardPosition]) {
        let cells = self.cells.filter { positions.contains($0.position) }
        cells.forEach { $0.highlight() }
    }

    func unHighlight(_ positions : [TTTBoardPosition]) {
        let cells = self.cells.filter { positions.contains($0.position) }
        cells.forEach { $0.unHighlight() }
    }

    func clear() {
        self.config = TTTBoardConfig.empty()
        unHighlight(self.cells.map { $0.position})
    }
}

/// MARK : Setup
private extension TTTBoard {
    func setupCellPositions() {
        let sortedCells = self.cells.sorted { cell1,cell2 in
            let isLeftOf =  cell1.frame.origin.x < cell2.frame.origin.x
            let isInSameRow = cell1.frame.origin.y == cell2.frame.origin.y
            let isAbove = cell1.frame.origin.y < cell2.frame.origin.y
            let isSortedBefore = isInSameRow ? isLeftOf : isAbove
            return isSortedBefore
        }
        let positions = Array(TTTBoardPositionSequence())
        let sortedCellsPositions = zip(sortedCells,positions)
        for (cell,position) in sortedCellsPositions
        {
            cell.position = position
        }
    }
    
    func setupTouchHandler() {
        for cell in cells {
            let recognizer = UITapGestureRecognizer(target: self, action:Selector.cellTouchHandler)
            cell.addGestureRecognizer(recognizer)
        }
    }
}