/**

  * 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.demo.minesweeper;

 import java.util.ArrayList;

 import java.util.List;

 import java.util.Random;

 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.Property;

 /** Model of the mine field.

  */

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

     @Property(name = "state", type = MinesModel.GameState.class),

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

 })

 final class MinesModel {

     enum GameState {

         IN_PROGRESS, WON, LOST;

     }

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

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

     })

     static class RowModel {

     }

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

         @Property(name = "state", type = SquareType.class),

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

     })

     static class SquareModel {

         @ComputedProperty static String text(SquareType state) {

             if (state == null) return " ";

             switch (state) {

                 case EXPLOSION: return "B";

                 case UNKNOWN: return "?";

                 case N_0: return " ";

             }

             return "" + state.ordinal();

         }

         @ComputedProperty static String style(SquareType state) {

             return state == null ? null : state.toString();

         }

     }

     enum SquareType {

         N_0, N_1, N_2, N_3, N_4, N_5, N_6, N_7, N_8,

         UNKNOWN, EXPLOSION, DISCOVERED;

         final boolean isVisible() {

             return name().startsWith("N_");

         }

         final SquareType moreBombsAround() {

             switch (this) {

                 case EXPLOSION:

                 case UNKNOWN:

                 case DISCOVERED:

                 case N_8:

                     return this;

             }

             return values()[ordinal() + 1];

         }

     }

     @ModelOperation static void init(Mines model, int width, int height, int mines) {

         List<Row> rows = new ArrayList<Row>(height);

         for (int y = 0; y < height; y++) {

             Square[] columns = new Square[width];

             for (int x = 0; x < width; x++) {

                 columns[x] = new Square(SquareType.UNKNOWN, false);

             }

             rows.add(new Row(columns));

         }

         Random r = new Random();

         while (mines > 0) {

             int x = r.nextInt(width);

             int y = r.nextInt(height);

             final Square s = rows.get(y).getColumns().get(x);

             if (s.isMine()) {

                 continue;

             }

             s.setMine(true);

             mines--;

         }

         model.setState(GameState.IN_PROGRESS);

         model.getRows().clear();

         model.getRows().addAll(rows);

     }

     @ModelOperation static void computeMines(Mines model) {

         List<Integer> xBombs = new ArrayList<Integer>();

         List<Integer> yBombs = new ArrayList<Integer>();

         final List<Row> rows = model.getRows();

         boolean emptyHidden = false;

         SquareType[][] arr = new SquareType[rows.size()][];

         for (int y = 0; y < rows.size(); y++) {

             final List<Square> columns = rows.get(y).getColumns();

             arr[y] = new SquareType[columns.size()];

             for (int x = 0; x < columns.size(); x++) {

                 Square sq = columns.get(x);

                 if (sq.isMine()) {

                     xBombs.add(x);

                     yBombs.add(y);

                 }

                 if (sq.getState().isVisible()) {

                     arr[y][x] = SquareType.N_0;

                 } else {

                     if (!sq.isMine()) {

                         emptyHidden = true;

                     }

                 }

             }

         }

         for (int i = 0; i < xBombs.size(); i++) {

             int x = xBombs.get(i);

             int y = yBombs.get(i);

             incrementAround(arr, x, y);

         }

         for (int y = 0; y < rows.size(); y++) {

             final List<Square> columns = rows.get(y).getColumns();

             for (int x = 0; x < columns.size(); x++) {

                 Square sq = columns.get(x);

                 final SquareType newState = arr[y][x];

                 if (newState != null && newState != sq.getState()) {

                     sq.setState(newState);

                 }

             }

         }

         if (!emptyHidden) {

             model.setState(GameState.WON);

             showAllBombs(model, SquareType.DISCOVERED);

         }

     }

     private static void incrementAround(SquareType[][] arr, int x, int y) {

         incrementAt(arr, x - 1, y - 1);

         incrementAt(arr, x - 1, y);

         incrementAt(arr, x - 1, y + 1);

         incrementAt(arr, x + 1, y - 1);

         incrementAt(arr, x + 1, y);

         incrementAt(arr, x + 1, y + 1);

         incrementAt(arr, x, y - 1);

         incrementAt(arr, x, y + 1);

     }

     private static void incrementAt(SquareType[][] arr, int x, int y) {

         if (y >= 0 && y < arr.length) {

             SquareType[] r = arr[y];

             if (x >= 0 && x < r.length) {

                 SquareType sq = r[x];

                 if (sq != null) {

                     r[x] = sq.moreBombsAround();

                 }

             }

         }

     }

     static void showAllBombs(Mines model, SquareType state) {

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

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

                 if (square.isMine()) {

                     square.setState(state);

                 }

             }

         }

     }

     @Function static void click(Mines model, Square data) {

         if (model.getState() != GameState.IN_PROGRESS) {

             return;

         }

         switch (data.getState()) {

             case UNKNOWN: 

                 if (data.isMine()) {

                     showAllBombs(model, SquareType.EXPLOSION);

                     model.setState(GameState.LOST);

                 } else {

                     expandKnown(model, data);

                 }

             break;

         }

     }

     private static void expandKnown(Mines model, Square data) {

         final List<Row> rows = model.getRows();

         for (int y = 0; y < rows.size(); y++) {

             final List<Square> columns = rows.get(y).getColumns();

             for (int x = 0; x < columns.size(); x++) {

                 Square sq = columns.get(x);

                 if (sq == data) {

                     expandKnown(model, x, y);

                     return;

                 }

             }

         }

     }

     private static void expandKnown(Mines model, int x , int y) {

         if (y < 0 || y >= model.getRows().size()) {

             return;

         }

         final List<Square> columns = model.getRows().get(y).getColumns();

         if (x < 0 || x >= columns.size()) {

             return;

         }

         final Square sq = columns.get(x);

         if (sq.getState() == SquareType.UNKNOWN) {

             sq.setState(SquareType.N_0);

             model.computeMines();

             if (sq.getState() == SquareType.N_0) {

                 expandKnown(model, x - 1, y - 1);

                 expandKnown(model, x - 1, y);

                 expandKnown(model, x - 1, y + 1);

                 expandKnown(model, x , y - 1);

                 expandKnown(model, x, y + 1);

                 expandKnown(model, x + 1, y - 1);

                 expandKnown(model, x + 1, y);

                 expandKnown(model, x + 1, y + 1);

             }

         }

     }

 }