//
//  File.swift
//  
//
//  Created by Louis DUFOUR on 15/01/2024.
//

import Foundation

public struct Board : Hashable, Equatable {
    public let nbRows: Int
    public let nbColumns: Int
    public private(set) var grid: [[Cell]]

    public init?(withGrid grid: [[Cell]]) {
        guard let firstRowLength = grid.first?.count, grid.allSatisfy({ $0.count == firstRowLength }) else {
            return nil
        }

        self.nbRows = grid.count
        self.nbColumns = firstRowLength
        self.grid=grid
    }

    public func getCell(atRow row: Int, atColumn column: Int) -> Cell? {
        guard row >= 0, row < nbRows, column >= 0, column < nbColumns else {
            return nil
        }
        return grid[row][column]
    }
    
    public func countPieces(of owner: Owner) -> Int {
        return grid.flatMap({ $0 }).filter({ $0.piece?.owner == owner }).count
    }
    
    public func countPieces() -> (player1: Int, player2: Int) {
        let player1Count = countPieces(of: .player1)
        let player2Count = countPieces(of: .player2)
        return (player1Count, player2Count)
    }
    
    public mutating func insert(piece: Piece, atRow row: Int, andColumn column: Int) -> BoardResult {
        guard row >= 0, row < nbRows, column >= 0, column < nbColumns else {
            return .failed(reason: .outOfBounds)
        }
        
        if grid[row][column].piece == nil {
            grid[row][column].piece = piece
            return .ok
        } else {
            return .failed(reason: .cellNotEmpty)
        }
    }

    public mutating func removePiece(atRow row: Int, andColumn column: Int) -> BoardResult {
        guard row >= 0, row < nbRows, column >= 0, column < nbColumns else {
            return .failed(reason: .outOfBounds)
        }
        
        if grid[row][column].piece != nil {
            grid[row][column].piece = nil
            return .ok
        } else {
            return .failed(reason: .cellEmpty)
        }
    }
    

}