/*

 * Copyright (c) 1999, 2003, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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/*

 * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved

 * (C) Copyright IBM Corp. 1996-1998 - All Rights Reserved

 *

 *   The original version of this source code and documentation is copyrighted

 * and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These

 * materials are provided under terms of a License Agreement between Taligent

 * and Sun. This technology is protected by multiple US and International

 * patents. This notice and attribution to Taligent may not be removed.

 *   Taligent is a registered trademark of Taligent, Inc.

 *

 */

package java.text;

import java.util.Vector;

import sun.text.UCompactIntArray;

import sun.text.IntHashtable;

/**

 * This class contains the static state of a RuleBasedCollator: The various

 * tables that are used by the collation routines.  Several RuleBasedCollators

 * can share a single RBCollationTables object, easing memory requirements and

 * improving performance.

 */

final class RBCollationTables {

    //===========================================================================================

    //  The following diagram shows the data structure of the RBCollationTables object.

    //  Suppose we have the rule, where 'o-umlaut' is the unicode char 0x00F6.

    //  "a, A < b, B < c, C, ch, cH, Ch, CH < d, D ... < o, O; 'o-umlaut'/E, 'O-umlaut'/E ...".

    //  What the rule says is, sorts 'ch'ligatures and 'c' only with tertiary difference and

    //  sorts 'o-umlaut' as if it's always expanded with 'e'.

    //

    // mapping table                     contracting list           expanding list

    // (contains all unicode char

    //  entries)                   ___    ____________       _________________________

    //  ________                +>|_*_|->|'c' |v('c') |  +>|v('o')|v('umlaut')|v('e')|

    // |_\u0001_|-> v('\u0001') | |_:_|  |------------|  | |-------------------------|

    // |_\u0002_|-> v('\u0002') | |_:_|  |'ch'|v('ch')|  | |             :           |

    // |____:___|               | |_:_|  |------------|  | |-------------------------|

    // |____:___|               |        |'cH'|v('cH')|  | |             :           |

    // |__'a'___|-> v('a')      |        |------------|  | |-------------------------|

    // |__'b'___|-> v('b')      |        |'Ch'|v('Ch')|  | |             :           |

    // |____:___|               |        |------------|  | |-------------------------|

    // |____:___|               |        |'CH'|v('CH')|  | |             :           |

    // |___'c'__|----------------         ------------   | |-------------------------|

    // |____:___|                                        | |             :           |

    // |o-umlaut|----------------------------------------  |_________________________|

    // |____:___|

    //

    // Noted by Helena Shih on 6/23/97

    //============================================================================================

    public RBCollationTables(String rules, int decmp) throws ParseException {

        this.rules = rules;

        RBTableBuilder builder = new RBTableBuilder(new BuildAPI());

        builder.build(rules, decmp); // this object is filled in through

                                            // the BuildAPI object

    }

    final class BuildAPI {

        /**

         * Private constructor.  Prevents anyone else besides RBTableBuilder

         * from gaining direct access to the internals of this class.

         */

        private BuildAPI() {

        }

        /**

         * This function is used by RBTableBuilder to fill in all the members of this

         * object.  (Effectively, the builder class functions as a "friend" of this

         * class, but to avoid changing too much of the logic, it carries around "shadow"

         * copies of all these variables until the end of the build process and then

         * copies them en masse into the actual tables object once all the construction

         * logic is complete.  This function does that "copying en masse".

         * @param f2ary The value for frenchSec (the French-secondary flag)

         * @param swap The value for SE Asian swapping rule

         * @param map The collator's character-mapping table (the value for mapping)

         * @param cTbl The collator's contracting-character table (the value for contractTable)

         * @param eTbl The collator's expanding-character table (the value for expandTable)

         * @param cFlgs The hash table of characters that participate in contracting-

         *              character sequences (the value for contractFlags)

         * @param mso The value for maxSecOrder

         * @param mto The value for maxTerOrder

         */

        void fillInTables(boolean f2ary,

                          boolean swap,

                          UCompactIntArray map,

                          Vector cTbl,

                          Vector eTbl,

                          IntHashtable cFlgs,

                          short mso,

                          short mto) {

            frenchSec = f2ary;

            seAsianSwapping = swap;

            mapping = map;

            contractTable = cTbl;

            expandTable = eTbl;

            contractFlags = cFlgs;

            maxSecOrder = mso;

            maxTerOrder = mto;

        }

    }

    /**

     * Gets the table-based rules for the collation object.

     * @return returns the collation rules that the table collation object

     * was created from.

     */

    public String getRules()

    {

        return rules;

    }

    public boolean isFrenchSec() {

        return frenchSec;

    }

    public boolean isSEAsianSwapping() {

        return seAsianSwapping;

    }

    // ==============================================================

    // internal (for use by CollationElementIterator)

    // ==============================================================

    /**

     *  Get the entry of hash table of the contracting string in the collation

     *  table.

     *  @param ch the starting character of the contracting string

     */

    Vector getContractValues(int ch)

    {

        int index = mapping.elementAt(ch);

        return getContractValuesImpl(index - CONTRACTCHARINDEX);

    }

    //get contract values from contractTable by index

    private Vector getContractValuesImpl(int index)

    {

        if (index >= 0)

        {

            return (Vector)contractTable.elementAt(index);

        }

        else // not found

        {

            return null;

        }

    }

    /**

     * Returns true if this character appears anywhere in a contracting

     * character sequence.  (Used by CollationElementIterator.setOffset().)

     */

    boolean usedInContractSeq(int c) {

        return contractFlags.get(c) == 1;

    }

    /**

      * Return the maximum length of any expansion sequences that end

      * with the specified comparison order.

      *

      * @param order a collation order returned by previous or next.

      * @return the maximum length of any expansion seuences ending

      *         with the specified order.

      *

      * @see CollationElementIterator#getMaxExpansion

      */

    int getMaxExpansion(int order)

    {

        int result = 1;

        if (expandTable != null) {

            // Right now this does a linear search through the entire

            // expandsion table.  If a collator had a large number of expansions,

            // this could cause a performance problem, but in practise that

            // rarely happens

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

                int[] valueList = (int [])expandTable.elementAt(i);

                int length = valueList.length;

                if (length > result && valueList[length-1] == order) {

                    result = length;

                }

            }

        }

        return result;

    }

    /**

     *  Get the entry of hash table of the expanding string in the collation

     *  table.

     *  @param idx the index of the expanding string value list

     */

    final int[] getExpandValueList(int order) {

        return (int[])expandTable.elementAt(order - EXPANDCHARINDEX);

    }

    /**

     *  Get the comarison order of a character from the collation table.

     *  @return the comparison order of a character.

     */

    int getUnicodeOrder(int ch)

    {

        return mapping.elementAt(ch);

    }

    short getMaxSecOrder() {

        return maxSecOrder;

    }

    short getMaxTerOrder() {

        return maxTerOrder;

    }

    /**

     * Reverse a string.

     */

    //shemran/Note: this is used for secondary order value reverse, no

    //              need to consider supplementary pair.

    static void reverse (StringBuffer result, int from, int to)

    {

        int i = from;

        char swap;

        int j = to - 1;

        while (i < j) {

            swap =  result.charAt(i);

            result.setCharAt(i, result.charAt(j));

            result.setCharAt(j, swap);

            i++;

            j--;

        }

    }

    final static int getEntry(Vector list, String name, boolean fwd) {

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

            EntryPair pair = (EntryPair)list.elementAt(i);

            if (pair.fwd == fwd && pair.entryName.equals(name)) {

                return i;

            }

        }

        return UNMAPPED;

    }

    // ==============================================================

    // constants

    // ==============================================================

    //sherman/Todo: is the value big enough?????

    final static int EXPANDCHARINDEX = 0x7E000000; // Expand index follows

    final static int CONTRACTCHARINDEX = 0x7F000000;  // contract indexes follow

    final static int UNMAPPED = 0xFFFFFFFF;

    final static int PRIMARYORDERMASK = 0xffff0000;

    final static int SECONDARYORDERMASK = 0x0000ff00;

    final static int TERTIARYORDERMASK = 0x000000ff;

    final static int PRIMARYDIFFERENCEONLY = 0xffff0000;

    final static int SECONDARYDIFFERENCEONLY = 0xffffff00;

    final static int PRIMARYORDERSHIFT = 16;

    final static int SECONDARYORDERSHIFT = 8;

    // ==============================================================

    // instance variables

    // ==============================================================

    private String rules = null;

    private boolean frenchSec = false;

    private boolean seAsianSwapping = false;

    private UCompactIntArray mapping = null;

    private Vector contractTable = null;

    private Vector expandTable = null;

    private IntHashtable contractFlags = null;

    private short maxSecOrder = 0;

    private short maxTerOrder = 0;

}