Throw away and redo most of board

+ filling notation points to score...

CustomTypes/Sources/CustomTypes/Display.swift

@@ -1,11 +1,11 @@
 import Model
 
-extension Piece: CustomStringConvertible {
+extension Player: CustomStringConvertible {
     public var description: String {
         switch self {
-        case .PlayerA:
+        case .A:
             "🔴"
-        case .PlayerB:
+        case .B:
             "🟡"
         }
     }
@@ -17,7 +17,7 @@ extension Board: CustomStringConvertible, CustomDebugStringConvertible {
         
         for row in 0..<self.rows {
             for col in 0..<self.columns {
-                str += self[col, row]?.description ?? "  "
+                str += self[col, row]?.owner.description ?? "⚪"
             }
             
             str += "\n"
@@ -27,8 +27,7 @@ extension Board: CustomStringConvertible, CustomDebugStringConvertible {
     }
     
     public var debugDescription: String {
-        let (a, b) = self.countPieces()
-        return "Board[\(self.columns)x\(self.rows), \(a) A and \(b) B pieces]"
+        return "Board[\(self.columns)x\(self.rows), \(self.countPieces { p in p.owner == .A }) A and \(self.countPieces { p in p.owner == .B }) B pieces]"
     }
 }
 

CustomTypes/Tests/CustomTypesTests/DisplayTests.swift

@@ -9,13 +9,13 @@ final class CustomTypesTests: XCTestCase {
             return
         }
         
-        board[1, 1] = .PlayerA
-        board[2, 1] = .PlayerA
-        board[2, 2] = .PlayerA
-        board[1, 2] = .PlayerB
+        board[1, 1] = Piece(owner: .A)
+        board[2, 1] = Piece(owner: .A)
+        board[2, 2] = Piece(owner: .A)
+        board[1, 2] = Piece(owner: .B)
         
         let text: String = board.description
         
-        XCTAssertEqual(text, "        \n  🔴🔴  \n  🟡🔴  \n        \n")
+        XCTAssertEqual(text, "⚪⚪⚪⚪\n⚪🔴🔴⚪\n⚪🟡🔴⚪\n⚪⚪⚪⚪\n")
     }
 }

Model/Sources/Model/Board.swift

@@ -16,128 +16,105 @@ public struct Board {
         self.grid = grid
 	}
     
-    private func checkBounds(_ column: Int, _ row: Int) {
-        precondition(column >= 0 && column < self.columns && row >= 0 && row < self.rows, "Coordinates out of bounds")
+    private func isInBounds(_ pos: Coords) -> Bool {
+        pos.col >= 0 && pos.col < self.columns && pos.row >= 0 && pos.row < self.rows
+    }
+    
+    private func ensureBounds(_ pos: Coords) {
+        precondition(isInBounds(pos), "Coordinates out of bounds")
     }
     
     public subscript(column: Int, row: Int) -> Piece? {
+        get { self[Coords(column, row)] }
+        
+        set { self[Coords(column, row)] = newValue }
+    }
+    
+    public subscript(pos: Coords) -> Piece? {
         get {
-            checkBounds(column, row)
-            return grid[column][row]
+            ensureBounds(pos)
+            return grid[pos.col][pos.row]
         }
         
-        set {
-            checkBounds(column, row)
-            grid[column][row] = newValue
+        set(piece) {
+            ensureBounds(pos)
+            grid[pos.col][pos.row] = piece
         }
     }
     
-    public func countPieces() -> (a: Int, b: Int) {
-        var a = 0
-        var b = 0
+    public func countPieces(filter: (Piece) -> Bool = { piece in true }) -> Int {
+        var count = 0
         
         for column in grid {
             for piece in column {
-                switch piece {
-                case .PlayerA:
-                    a += 1
-                case .PlayerB:
-                    b += 1
-                case nil:
-                    break
+                if let piece = piece {
+                    if filter(piece) {
+                        count += 1
+                    }
                 }
             }
         }
         
-        return (a, b)
+        return count
     }
     
-    @discardableResult
-    public mutating func insert(piece: Piece, side: Side = .Top, offset: Int, pushing push: Bool = false) -> Bool {
+    // insertion coordinate computation is intentionally separated from actual insertion because the user may want to
+    // display a where the piece would end-up before doing the actual insertion
+    
+    public func getInsertionCoordinates(direction: Direction, offset: Int) -> Coords {
         precondition(offset >= 0, "Offset out of bounds")
         
-        switch side {
+        switch direction {
         case .Top:
             precondition(offset < self.columns, "Offset (column) out of bounds")
-            
-            if self.grid[offset].first! != nil {
-                if (!push) {
-                    return false
-                }
-                
-                Board.shiftDown(column: &self.grid[offset])
-            }
-            
-            self.grid[offset][0] = piece
-            
-            return true
+            return Coords(offset, 0)
         case .Left:
             precondition(offset < self.rows, "Offset (row) out of bounds")
-            
-            if self.grid.first![offset] != nil {
-                if (!push) {
-                    return false
-                }
-                
-                self.shiftRight(row: offset)
-            }
-            
-            self.grid[0][offset] = piece
-            
-            return true
+            return Coords(0, offset)
         case .Bottom:
             precondition(offset < self.columns, "Offset (column) out of bounds")
-            
-            if self.grid[offset].last! != nil {
-                if (!push) {
-                    return false
-                }
-                
-                Board.shiftUp(column: &self.grid[offset])
-            }
-            
-            let lastIndex = self.grid[offset].count - 1
-            self.grid[offset][lastIndex] = piece
-            
-            return true
+            return Coords(offset, self.rows - 1)
         case .Right:
             precondition(offset < self.rows, "Offset (row) out of bounds")
-            
-            if self.grid.last![offset] != nil {
-                if (!push) {
-                    return false
+            return Coords(self.columns - 1, offset)
+        }
     }
     
-                self.shiftLeft(row: offset)
+    public enum FallResult: Equatable {
+        case Border(at: Coords)
+        case Piece(at: Coords, touched: Coords)
+        case Occupied
     }
     
-            self.grid[self.columns - 1][offset] = piece
+    public func fallCoordinates(initialCoords: Coords, direction: Direction) -> FallResult {
+        ensureBounds(initialCoords)
         
-            return true
-        }
+        let dir: (dc: Int, dr: Int) = switch direction {
+        case .Top: (0, -1)
+        case .Left: (-1, 0)
+        case .Bottom: (0, 1)
+        case .Right: (1, 0)
         }
         
-    private static func shiftDown(column: inout [Piece?]) {
-        for i in (1..<column.count).reversed() {
-            column[i] = column[i - 1]
-        }
+        if (self[initialCoords] != nil) {
+            return FallResult.Occupied
         }
         
-    private static func shiftUp(column: inout [Piece?]) {
-        for i in 0..<(column.count - 1) {
-            column[i] = column[i + 1]
-        }
-    }
+        var coords = initialCoords
+        var next: Coords
+        while true {
+            next = Coords(coords.col + dir.dc, coords.row + dir.dr)
             
-    private mutating func shiftLeft(row: Int) {
-        for i in 0..<(grid.count - 1) {
-            self.grid[i][row] = self.grid[i + 1][row]
-        }
+            if !isInBounds(next) {
+                return FallResult.Border(at: coords)
+            } else if self[next] != nil {
+                return FallResult.Piece(at: coords, touched: next)
             }
             
-    private mutating func shiftRight(row: Int) {
-        for i in 1..<grid.count {
-            self.grid[i - 1][row] = self.grid[i][row]
+            coords.col = next.col
+            coords.row = next.row
         }
     }
+    
+    // TODO push
 }

Model/Sources/Model/Coords.swift

@@ -0,0 +1,14 @@
+// public typealias Coords = (col: Int, row: Int)
+public struct Coords: Equatable {
+    var col: Int
+    var row: Int
+    
+    public init(_ col: Int, _ row: Int) {
+        self.col = col
+        self.row = row
+    }
+    
+    public init(pair: (Int, Int)) {
+        self.init(pair.0, pair.1)
+    }
+}

Model/Sources/Model/Direction.swift

@@ -0,0 +1,16 @@
+public enum Direction {
+    case Top, Left, Bottom, Right
+    
+    var opposite: Self {
+        switch self {
+        case .Top:
+                .Bottom
+        case .Left:
+                .Right
+        case .Bottom:
+                .Top
+        case .Right:
+                .Left
+        }
+    }
+}

Model/Sources/Model/Piece.swift

@@ -1,3 +1,8 @@
-public enum Piece {
-    case PlayerA, PlayerB
+public struct Piece {
+    public let owner: Player
+    
+    // Required for public visibility
+    public init(owner: Player) {
+        self.owner = owner
+    }
 }

Model/Sources/Model/Player.swift

@@ -0,0 +1,3 @@
+public enum Player {
+    case A, B
+}

Model/Sources/Model/Side.swift

@@ -1,3 +0,0 @@
-public enum Side {
-    case Top, Left, Bottom, Right
-}

Model/Tests/ModelTests/EmptyBoardTests.swift

@@ -4,7 +4,7 @@ import XCTest
 final class EmptyBoardTests: XCTestCase {
     private var board: Board!
     
-    override func setUp() {
+    override func setUpWithError() throws {
         super.setUp()
         
         guard let board = Board(columns: 5, rows: 6) else {
@@ -26,41 +26,128 @@ final class EmptyBoardTests: XCTestCase {
     func testEmptyByDefault() throws {
         XCTAssertNil(board[1, 1])
         let result = board.countPieces()
-        XCTAssertEqual(result.a, 0)
-        XCTAssertEqual(result.b, 0)
+        XCTAssertEqual(result, 0)
     }
     
-    func testSetGet() throws {
-        board[1, 1] = Piece.PlayerA;
+    func testCustomSubscript() throws {
+        for r in 0..<board.rows {
+            for c in 0..<board.columns {
+                for p: Player in [.A, .B] {
+                    try self.setUpWithError()
                     
-        XCTAssertEqual(board[1, 1], .PlayerA)
+                    try self._testCustomSubscript(at: Coords(c, r), player: p)
+                    
+                    try self.tearDownWithError()
+                }
+            }
+        }
+    }
+    
+    private func _testCustomSubscript(at: Coords, player: Player) throws {
+        board[at] = Piece(owner: player)
+        
+        XCTAssertEqual(board[at]?.owner, player)
     }
     
     func testCounts() throws {
-        board[1, 2] = .PlayerB
+        board[1, 2] = Piece(owner: .B)
+        board[0, 2] = Piece(owner: .A)
+        board[1, 1] = Piece(owner: .A)
         
-        let counts = board.countPieces()
-        XCTAssertEqual(counts.a, 0)
-        XCTAssertEqual(counts.b, 1)
+        XCTAssertEqual(board.countPieces { piece in piece.owner == .A }, 2)
+        XCTAssertEqual(board.countPieces { piece in piece.owner == .B }, 1)
     }
     
-    func testInsertTopNoPush() {
-        XCTAssert(board.insert(piece: .PlayerA, side: .Top, offset: 2))
-        XCTAssertEqual(board[2, 0], .PlayerA)
+    func testInsertsSides() throws {
+        for (side, offset, expected): (Direction, Int, (Int, Int)) in [
+            (.Top, 0, (0, 0)),
+            (.Left, 0, (0, 0)),
+            (.Bottom, 0, (0, 5)),
+            (.Right, 0, (4, 0)),
+            /* ... */
+            (.Top, 4, (4, 0)),
+            (.Left, 5, (0, 5)),
+            (.Bottom, 4, (4, 5)),
+            (.Right, 5, (4, 5)),
+        ] {
+            try self.setUpWithError()
+            
+            try self._testInsertSide(side: side, offset: offset, expectedCoords: Coords(pair: expected))
+            
+            try self.tearDownWithError()
         }
+    }
+    
+    private func _testInsertSide(side: Direction, offset: Int, expectedCoords: Coords) throws {
+        let result = board.getInsertionCoordinates(direction: side, offset: offset)
         
-    func testInsertBottomNoPush() {
-        XCTAssert(board.insert(piece: .PlayerB, side: .Bottom, offset: 2))
-        XCTAssertEqual(board[2, board.rows - 1], .PlayerB)
+        // Note: Not sure I want Coordinates to be a simple tuple or a struct, as both have advantages that the other dont:
+        // Tuples can be initialized like so (col, row) which I find quite handy
+        // Structs supports == operators
+        // ...
+        XCTAssertEqual(result.col, expectedCoords.col)
+        XCTAssertEqual(result.row, expectedCoords.row)
     }
     
-    func testInsertLeftNoPush() {
-        XCTAssert(board.insert(piece: .PlayerA, side: .Left, offset: 2))
-        XCTAssertEqual(board[0, 2], .PlayerA)
+    func testInsertsFallNoPiece() throws {
+        for (from, direction, expected): ((Int, Int), Direction, (Int, Int)) in [
+            ((0, 0), .Bottom, (0, 5)),
+            ((0, 0), .Left, (0, 0)),
+            ((0, 0), .Right, (4, 0)),
+            ((0, 0), .Top, (0, 0)),
+            /* ... */
+            ((4, 5), .Bottom, (4, 5)),
+            ((4, 5), .Left, (0, 5)),
+            ((4, 5), .Right, (4, 5)),
+            ((4, 5), .Top, (4, 0)),
+        ] {
+            try self.setUpWithError()
+            
+            try self._testInsertFall(from: Coords(pair: from), dir: direction, expectedCoords: .Border(at: Coords(pair: expected)))
+            
+            try self.tearDownWithError()
+        }
+    }
+    
+    func testInsertsFallOnPiece() throws {
+        for (from, direction, (expected, touched)): ((Int, Int), Direction, ((Int, Int), (Int, Int))) in [
+            ((0, 0), .Bottom, ((0, 1), (0, 2))),
+            ((0, 0), .Right, ((1, 0), (2, 0))),
+            ((4, 5), .Left, ((3, 5), (2, 5))),
+            ((4, 5), .Top, ((4, 3), (4, 2))),
+        ] {
+            try self.setUpWithError()
+            
+            // Place some pieces
+            for pos in [
+                                (2, 0),
+                                (2, 1),
+                (0, 2), (1, 2), (2, 2), (3, 2), (4, 2),
+                                (2, 3),
+                                (2, 4),
+                                (2, 5),
+            ] {
+                // ensure it works with any player
+                board[Coords(pair: pos)] = if (pos.0 + pos.1) & 1 == 1 {
+                    Piece(owner: .A)
+                } else {
+                    Piece(owner: .B)
+                }
             }
             
-    func testInsertRightNoPush() {
-        XCTAssert(board.insert(piece: .PlayerB, side: .Right, offset: 2))
-        XCTAssertEqual(board[board.columns - 1, 2], .PlayerB)
+            try self._testInsertFall(
+                from: Coords(pair: from),
+                dir: direction,
+                expectedCoords: .Piece(at: Coords(pair: expected), touched: Coords(pair: touched))
+            )
+            
+            try self.tearDownWithError()
+        }
+    }
+    
+    private func _testInsertFall(from: Coords, dir: Direction, expectedCoords: Board.FallResult) throws {
+        let result = board.fallCoordinates(initialCoords: from, direction: dir)
+        
+        XCTAssertEqual(result, expectedCoords)
     }
 }

Model/Tests/ModelTests/FilledBoardTests.swift

@@ -15,9 +15,9 @@ final class FilledBoardTests: XCTestCase {
         for row in 0..<board.rows {
             for col in 0..<board.columns {
                 board[col, row] = if (row & 1) == 1 {
-                    .PlayerA
+                    Piece(owner: .A)
                 } else {
-                    .PlayerB
+                    Piece(owner: .B)
                 }
             }
         }
@@ -25,29 +25,33 @@ final class FilledBoardTests: XCTestCase {
         self.board = board
     }
     
-    func testInsertFailTopNoPush() {
-        let before = board[2, 0]
-        XCTAssertFalse(board.insert(piece: .PlayerA, side: .Top, offset: 2))
-        XCTAssertEqual(before, board[2, 0])
-    }
+    func testRemovePiece() throws {
+        board[1, 2] = nil
         
-    func testInsertFailBottomNoPush() {
-        let before = board[2, board.rows - 1]
-        XCTAssertFalse(board.insert(piece: .PlayerB, side: .Bottom, offset: 2))
-        XCTAssertEqual(before, board[2, board.rows - 1])
+        XCTAssertNil(board[1, 2])
     }
     
-    func testInsertFailLeftNoPush() {
-        let before = board[2, 0]
-        XCTAssertFalse(board.insert(piece: .PlayerA, side: .Left, offset: 2))
-        XCTAssertEqual(before, board[0, 2])
-    }
+    func testInsertsFallFail() throws {
+        for (from, direction): ((Int, Int), Direction) in [
+            ((0, 0), .Bottom),
+            ((0, 0), .Right),
+            ((4, 5), .Left),
+            ((4, 5), .Top),
+            
+            ((4, 5), .Bottom),
+            ((4, 5), .Right),
+            ((0, 0), .Left),
+            ((0, 0), .Top),
+        ] {
+            try self.setUpWithError()
             
-    func testInsertFailRightNoPush() {
-        let before = board[board.columns - 1, 2]
-        XCTAssertFalse(board.insert(piece: .PlayerB, side: .Right, offset: 2))
-        XCTAssertEqual(before, board[board.columns - 1, 2])
+            try self._testInsertFallFail(from: Coords(pair: from), dir: direction)
+            
+            try self.tearDownWithError()
+        }
     }
     
-    // TODO Test shifting
+    private func _testInsertFallFail(from: Coords, dir: Direction) throws {
+        XCTAssertEqual(board.fallCoordinates(initialCoords: from, direction: dir), .Occupied)
+    }
 }