/**

 * The MIT License (MIT)

 *

 * Copyright (C) 2013 Jaroslav Tulach <jaroslav.tulach@apidesign.org>

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

package org.apidesign.html.demo.chess;

import java.util.Arrays;

import java.util.Collections;

import java.util.List;

import java.util.Timer;

import java.util.TimerTask;

import net.java.html.json.ComputedProperty;

import net.java.html.json.Function;

import net.java.html.json.Model;

import net.java.html.json.ModelOperation;

import net.java.html.json.OnPropertyChange;

import net.java.html.json.Property;

import net.java.html.sound.AudioClip;

@Model(className="Board", properties={

    @Property(name = "player", type = String.class),

    @Property(name = "gameId", type = String.class),

    @Property(name = "whitePlayer", type = String.class),

    @Property(name = "blackPlayer", type = String.class),

    @Property(name = "alertMessage", type = String.class),

    @Property(name = "status", type = String.class),

    @Property(name = "rows", type = Row.class, array = true),

    @Property(name = "turn", type = Color.class),

    @Property(name = "moves", type = Move.class, array = true),

    @Property(name = "pendingMove", type = Move.class),

    @Property(name = "active", type = boolean.class),

})

public class BoardModel {

    @ComputedProperty static String title(String status, String gameId) {

        String t = status != null ? status : gameId;

        if (t != null && t.length() > 10) {

            return t.substring(0, 10);

        }

        return t;

    }

    @ModelOperation static void updateSummary(Board b, String summary) {

        if (summary != null) {

            b.setStatus(summary);

        }

    }

    @ComputedProperty static boolean myTurn(String player, String whitePlayer, String blackPlayer, Color turn) {

        if (turn != null && player != null) switch (turn) {

            case B: return player.equals(blackPlayer);

            case W: return player.equals(whitePlayer);

        }

        return false;

    }

    @ComputedProperty static boolean justObserving(String player) {

        return player == null;

    }

    private static final AudioClip MOVE = AudioClip.create("sounds/move.mp3");

    @OnPropertyChange("moves") static void playMove() {

        MOVE.play();

    }

    private static final AudioClip CHECK = AudioClip.create("sounds/check.mp3");

    private static final AudioClip CHECKMATE = AudioClip.create("sounds/checkmate.mp3");

    @Function static void selected(Board b, Square data) {

        if (!b.isMyTurn()) {

            b.setAlertMessage("Not your turn!");

            return;

        }

        Square previoslySelected = findSelectedSquare(b);

        if (previoslySelected == null) {

            if (data.getPiece() != null && data.getPieceColor() == b.getTurn()) {

                data.setSelected(true);

                Rules.computeAccessible(b, data);

            }

        } else {

            if (previoslySelected == data) {

                data.setSelected(false);

                Rules.computeAccessible(b, null);

                return;

            }

            if (data.getPiece() != null && data.getPieceColor() == previoslySelected.getPieceColor()) {

                previoslySelected.setSelected(false);

                data.setSelected(true);

                Rules.computeAccessible(b, data);

                return;

            }

            if (data.isAccessible()) {

                previoslySelected.setSelected(false);

                Move newMove = new Move();

                newMove.setFrom(previoslySelected.getPosition());

                newMove.setTo(data.getPosition());

                newMove.setRound(b.getMoves().size() / 2 + 1);

                newMove.setPiece(previoslySelected.getPiece());

                newMove.setTurn(previoslySelected.getPieceColor());

                newMove.setTakes(data.getPiece() != null);

                b.getMoves().add(newMove);

                b.setPendingMove(newMove);

                data.setPending(true);

                data.setPieceColor(previoslySelected.getPieceColor());

                data.setPiece(previoslySelected.getPiece());

                b.setTurn(null);

                previoslySelected.setPiece(null);

                previoslySelected.setPieceColor(null);

                Rules.computeAccessible(b, null);

            }

        }

    }

    static class NextMove extends TimerTask {

        private static final Timer T = new Timer("Animate moves");

        private final Board b;

        private final Move m;

        public NextMove(Board b, Move m) {

            this.b = b;

            this.m = m;

            T.schedule(this, 1000);

        }

        @Override

        public void run() {

            b.showPosition(m);

        }

    }

    @ModelOperation @Function static void showPosition(Board b, Move data) {

        Rules.initBoard(b);

        boolean found = false;

        for (Move m : b.getMoves()) {

            if (found) {

                b.setTurn(null);

                new NextMove(b, m);

                return;

            }

            Square from = findSquare(b, (char)m.getFrom().getX(), m.getFrom().getY());

            Square to = findSquare(b, (char)m.getTo().getX(), m.getTo().getY());

            to.setPiece(from.getPiece());

            to.setPieceColor(from.getPieceColor());

            from.setPiece(null);

            from.setPieceColor(null);

            if (m == data) {

                found = true;

            }

        }

        b.setTurn(b.getMoves().size() % 2 == 0 ? Color.W : Color.B);

    }

    @Function static void rotateBoard(Board b) {

        Collections.reverse(b.getRows());

        for (Row r : b.getRows()) {

            Collections.reverse(r.getColumns());

        }

        Square sq = findSelectedSquare(b);

        if (sq != null) {

            sq.setSelected(false);

            Rules.computeAccessible(b, null);

        }

    }

    @ComputedProperty static boolean whiteTurn(Color turn) {

        return turn == Color.W;

    }

    @ComputedProperty static boolean blackTurn(Color turn) {

        return turn == Color.B;

    }

    @ComputedProperty static List<String> columnNames(List<Row> rows) {

        boolean whiteDown = rows.isEmpty() || rows.get(0).getY() == 8;

        String[] arr = new String[8];

        for (int i = 0; i < 8; i++) {

            String s;

            if (whiteDown) {

                s = "" + (char)('A' + i);

            } else {

                s = "" + (char)('H' - i);

            }

            arr[i] = s;

        }

        return Arrays.asList(arr);

    }

    static Square findSquare(Board b, char column, int row) {

        for (Row r : b.getRows()) {

            for (Square square : r.getColumns()) {

                if (square.getPosition().getX() == column && square.getPosition().getY() == row) {

                    return square;

                }

            }

        }

        return null;

    }

    private static Square findSquare(Board b, Position to) {

        return findSquare(b, (char)to.getX(), to.getY());

    }

    static Square findSelectedSquare(Board b) {

        for (Row row : b.getRows()) {

            for (Square square : row.getColumns()) {

                if (square.isSelected()) {

                    return square;

                }

            }

        }

        return null;

    }

    static void moveResponse(

        final Board b, final String errMsg, 

        final List<String> whites, final List<String> blacks, 

        final Color turn, Object alert

    ) {

        if (errMsg != null) {

            b.getMoves().remove(b.getPendingMove());

            b.setPendingMove(null);

            b.setAlertMessage(errMsg);

        } else {

            b.setTurn(turn);

            b.setAlertMessage(null);

        }

        Rules.initBoard(b, whites, blacks, turn);

    }

    static void moveUpdate(

        final Board b, final Move move, 

        final List<String> whites, final List<String> blacks, 

        final Color turn, Object alert

    ) {

        final Square from = BoardModel.findSquare(b, move.getFrom());

        final Square to = BoardModel.findSquare(b, move.getTo());

        move.setPiece(from.getPiece());

        move.setTurn(from.getPieceColor());

        if (to.getPiece() != null) {

            move.setTakes(true);

        }

        move.setRound(b.getMoves().size() / 2 + 1);

        b.getMoves().add(move);

        Rules.initBoard(b, whites, blacks, turn);

    }

    @Model(className="Row", properties = {

        @Property(name = "columns", type = Square.class, array = true)

    })

    static class RowsImpl {

        @ComputedProperty static int y(List<Square> columns) {

            return columns.isEmpty() ? 0 : columns.get(0).getY();

        }

    }

    enum PieceType {

        PAWN(5), ROCK(2), KNIGHT(4), BISHOP(3), QUEEN(1), KING(0);

        final int entityIndex;

        PieceType(int ei) {

            this.entityIndex = ei;

        }

        static PieceType fromNotation(char notation) {

            switch (notation) {

                case 'R': return ROCK;

                case 'N': return KNIGHT;

                case 'B': return BISHOP;

                case 'Q': return QUEEN;

                case 'K': return KING;

                case 'P': return PAWN;

            }

            throw new IllegalStateException("Unexpected: " + notation);

        }

        String computeEntity(Color color) {

            if (color == null) {

                color = Color.W;

            }

            int base;

            switch (color) {

                case W: base = 12; break;

                case B: base = 18; break;

                default:

                    throw new AssertionError();

            }

            return "&#98" + String.valueOf(base + entityIndex) + ";";

        }

    }

    @Model(className="Position", properties = {

        @Property(name = "x", type = char.class),

        @Property(name = "y", type = int.class),

    })

    static class PositionImpl {

        @ComputedProperty static String location(int x, int y) {

            return "" + (char)(x - 'A' + 'a') + y;

        }

    }

    @Model(className="Square", properties = {

        @Property(name = "position", type = Position.class),

        @Property(name = "color", type = Color.class),

        @Property(name = "piece", type = PieceType.class),

        @Property(name = "pieceColor", type = Color.class),

        @Property(name = "selected", type = boolean.class),

        @Property(name = "accessible", type = boolean.class),

        @Property(name = "pending", type = boolean.class),

    })

    static class SquareModel {

        @ComputedProperty static String pieceEntity(

            PieceType piece, Color pieceColor

        ) {

            if (piece == null) {

                return "";

            }

            return piece.computeEntity(pieceColor);

        }

        @ComputedProperty static String squareColor(

            Color color, boolean selected, boolean accessible, boolean pending

        ) {

            if (selected) {

                return "selected";

            }

            if (accessible) {

                return "accessible";

            }

            if (pending) {

                return "pending";

            }

            if (color == null) {

                return "";

            } else {

                if (color == Color.W) {

                    return "white";

                } else {

                    return "black";

                }

            }

        }

        @ComputedProperty static char x(Position position) {

            return position == null ? 'A' : position.getX();

        }

        @ComputedProperty static int y(Position position) {

            return position == null ? 1 : position.getY();

        }

    }

    @Model(className = "Move", properties = {

        @Property(name = "round", type = int.class),

        @Property(name = "turn", type = Color.class),

        @Property(name = "piece", type = PieceType.class),

        @Property(name = "from", type = Position.class),

        @Property(name = "to", type = Position.class),

        @Property(name = "promoted", type = PieceType.class),

        @Property(name = "takes", type = boolean.class),

        @Property(name = "check", type = boolean.class),

    })

    static class MoveImpl {

        @ComputedProperty static boolean whiteMove(Color turn) {

            return turn == Color.W;

        }

        @ComputedProperty static String html(

            Position from, Position to, boolean takes, PieceType piece, Color turn

        ) {

            if (from == null || to == null) {

                return "";

            }

            StringBuilder sb = new StringBuilder();

            if (piece != null && piece != PieceType.PAWN) {

                sb.append(piece.computeEntity(turn));

            }

            sb.append(from.getLocation());

            if (takes) {

                sb.append("x");

            }

            sb.append(to.getLocation());

            return sb.toString();

        }

        static Move valueOf(String move) {

            move = move.toUpperCase();

            Move m = new Move();

            {

                Position p = new Position();

                p.setX(move.charAt(0));

                p.setY(move.charAt(1) - '0');

                m.setFrom(p);

            }

            {

                Position p = new Position();

                p.setX(move.charAt(2));

                p.setY(move.charAt(3) - '0');

                m.setTo(p);

            }

            return m;

        }

    }

}