/* vim: set expandtab tabstop=4 shiftwidth=4 : */

import java.util.Set;
import java.util.HashSet;

public class BoggleSolver
{
    private int cols, rows;
    private BoggleHybridTST dict;
    private BoggleBoard board;
    private boolean[] visited;
    private Set<String> result;

    // assume each word in the dictionary contains only [A-Z]
    public BoggleSolver(String[] dictionary)
    {
        dict = new BoggleHybridTST();
        for (String word : dictionary)
            dict.put(word);
    }

    // Returns the set of all valid words in the given Boggle board
    public Iterable<String> getAllValidWords(BoggleBoard b)
    {
        this.board = b;
        this.cols = board.cols();
        this.rows = board.rows();
        this.result = new HashSet<String>();

        for (int r = 0; r < this.rows; r++) {
            for (int c = 0; c < this.cols; c++) {
                this.visited = new boolean[this.rows * this.cols];
                explore(r, c, dict.emptyNode(), new StringBuilder(), 0);
            }
        }

        return result;
    }

    //
    private void explore(int r, int c, BoggleHybridTST.Node parent,
            StringBuilder s, int l)
    {
        if ((r < 0) || (r >= rows) || (c < 0) || (c >= cols)) return;

        int visitedIdx = (r * this.cols) + c;
        if (visited[visitedIdx]) return;

        boolean isQu = false;
        char ch = board.getLetter(r, c);

        BoggleHybridTST.Node next = dict.filter(ch, parent, s, l);
        if (next == null) return;
        l += 1;
        s.append(ch);
        if (ch == 'Q') {
            next = dict.filter('U', next, s, l);
            if (next == null) {
                s.setLength(l - 1);
                return;
            }
            isQu = true;
            l += 1;
            s.append('U');
        }

        if (next.isWord()) result.add(s.toString());

        visited[visitedIdx] = true;

        explore((r - 1), (c - 1), next, s, l);
        explore((r - 1), c, next, s, l);
        explore((r - 1), (c + 1), next, s, l);
        explore(r, (c - 1), next, s, l);
        explore(r, (c + 1), next, s, l);
        explore((r + 1), (c - 1), next, s, l);
        explore((r + 1), c, next, s, l);
        explore((r + 1), (c + 1), next, s, l);

        visited[visitedIdx] = false;
        if (isQu) s.setLength(l - 2);
        else s.setLength(l - 1);
    }

    // Returns the score if it is in the dictionary, zero otherwise.
    // assume the word contains only [A-Z]
    public int scoreOf(String word)
    {
        if (!dict.contains(word)) return 0;

        int l = word.length();
        if (l < 3) {
            return 0;
        } else if (l < 5) {
            return 1;
        } else if (l < 6) {
            return 2;
        } else if (l < 7) {
            return 3;
        } else if (l < 8) {
            return 5;
        } else {
            return 11;
        }
    }

    public static void main(String[] args)
    {
        if (args[0].equals("timing")) {
            In in = new In("./data/dictionary-yawl.txt");
            String[] dictionary = in.readAllStrings();

            Stopwatch w = new Stopwatch();
            BoggleSolver solver = new BoggleSolver(dictionary);
            double dt = +w.elapsedTime();
            System.out.println("construction : "+dt);

            String s = "board-pneumonoultramicroscopicsilicovolcanoconiosis.txt";
            BoggleBoard []boards = new BoggleBoard[5];
            boards[0] = new BoggleBoard("./data/board-points4527.txt");
            boards[1] = new BoggleBoard("./data/board-points13464.txt");
            boards[2] = new BoggleBoard("./data/board-points4410.txt");
            boards[3] = new BoggleBoard("./data/board-points1250.txt");
            boards[4] = new BoggleBoard("./data/board-points1500.txt");
            // boards[1] = new BoggleBoard("./data/board-rotavator.txt");
            // boards[2] = new BoggleBoard("./data/board-16q.txt");
            // boards[4] = new BoggleBoard("./data/" + s);


            for (int t = 0; t < 5; t++) {
                w = new Stopwatch();
                for (int i = 0; i < 3000; i++) {
                    solver.getAllValidWords(boards[i % 5]);
                }
                dt = +w.elapsedTime();
                System.out.println("search time : "+dt);
            }
        } else {
            In in = new In(args[0]);
            String[] dictionary = in.readAllStrings();
            BoggleSolver solver = new BoggleSolver(dictionary);
            BoggleBoard board = new BoggleBoard(args[1]);
            int score = 0;
            for (String word : solver.getAllValidWords(board))
            {
                StdOut.println(word);
                score += solver.scoreOf(word);
            }
            StdOut.println("Score = " + score);
            StdOut.println("Score = " + solver.scoreOf("REQUEST"));
        }
    }
}