(game "Diagonals (2002)"
    (players 2)
    (equipment {
        (board (rectangle 5 10) use:Vertex)
        (piece "Ball" Each)
        (piece "Ball" Neutral)
    })
    (rules
        (start {
            (place "Ball1" (intersection (expand (sites Bottom)) (sites Right)))
            (place "Ball2" (intersection (expand (sites Top)) (sites Left)))
        })
        (play 
            (or
                (move Add (to (intersection (sites Direction from:(sites Occupied by:Mover) Diagonal stop:(is Occupied (to))) (sites Empty))))
                (move Select
                    (from
                        (forEach (sites Occupied by:Next)
                            if:(!= 0 (count Sites in:(intersection (sites LineOfSight at:(site) Diagonal) (sites Occupied by:Mover))))
                        )
                    )
                    (then
                        (and
                            (remove (last To))
                            (add (piece (id "Ball" Neutral)) (to (last To)))
                        )
                    )
                )
            )
        )
        (end (if (and (no Moves P1) (no Moves P2))
                (byScore {
                    (score P1 (count Pieces P1))
                    (score P2 (count Pieces P2))
                })
            )
        )
    )
)

//------------------------------------------------------------------------------

(metadata 
    
    (info
        {
        (description "This game is played in a 5x10 square board.")
        (rules "MOVE - On each turn, a player may do one of the following actions:
            - Drop a friendly stone at an empty cell, which is in a diagonal line of sight with another friendly stone, i.e., both stones must be separated by a diagonal line of empty cells. 
            - Transform an enemy stone, at a diagonal line of sight of a friendly stone, into a wall (which is a neutral stone).
            
        GOAL - When there are no valid moves, wins the player with more friendly stones.")
        (id "1819")
        (source "<a href=\"http://www.di.fc.ul.pt/~jpn/gv/diagonals2.htm\" target=\"_blank\" class=\"style1\" style=\"color: #0000EE\" />www.di.fc.ul.pt</a>")
        (version "1.3.13")
        (classification "board/war/replacement/eliminate/all")
        (author "Walter Joris")
        (credit "Eric Piette")
        (date "2002")
        }
    )
    
    (graphics {
        (show Edges Diagonal (colour Hidden))
        (board Colour OuterEdges (colour Black))
        (board Colour InnerEdges (colour Black))
        (board Colour OuterVertices (colour Hidden))
        (board Colour InnerVertices (colour Hidden))
        (player Colour Neutral (colour Red))
        (show Symbol "disc" (sites Corners) fillColour:(colour Black) edgeColour:(colour Black) scale:0.3)
    })
    
    (ai
        "Diagonals (2002)_ai"
    )
)