/*
 * Copyright (c) 2002, 2023, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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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 */

package java.lang;

import jdk.internal.vm.annotation.IntrinsicCandidate;
import jdk.internal.vm.annotation.Stable;

/** The CharacterDataLatin1 class encapsulates the large tables found in
    Java.lang.Character. */

final class CharacterDataLatin1 extends CharacterData {

    /* The character properties are currently encoded into 32 bits in the following manner:
        1 bit   mirrored property
        4 bits  directionality property
        9 bits  signed offset used for converting case
        1 bit   if 1, adding the signed offset converts the character to lowercase
        1 bit   if 1, subtracting the signed offset converts the character to uppercase
        1 bit   if 1, this character has a titlecase equivalent (possibly itself)
        3 bits  0  may not be part of an identifier
                1  ignorable control; may continue a Unicode identifier or Java identifier
                2  may continue a Java identifier but not a Unicode identifier (unused)
                3  may continue a Unicode identifier or Java identifier
                4  is a Java whitespace character
                5  may start or continue a Java identifier;
                   may continue but not start a Unicode identifier (underscores)
                6  may start or continue a Java identifier but not a Unicode identifier ($)
                7  may start or continue a Unicode identifier or Java identifier
                Thus:
                   5, 6, 7 may start a Java identifier
                   1, 2, 3, 5, 6, 7 may continue a Java identifier
                   7 may start a Unicode identifier
                   1, 3, 5, 7 may continue a Unicode identifier
                   1 is ignorable within an identifier
                   4 is Java whitespace
        2 bits  0  this character has no numeric property
                1  adding the digit offset to the character code and then
                   masking with 0x1F will produce the desired numeric value
                2  this character has a "strange" numeric value
                3  a Java supradecimal digit: adding the digit offset to the
                   character code, then masking with 0x1F, then adding 10
                   will produce the desired numeric value
        5 bits  digit offset
        5 bits  character type

        The encoding of character properties is subject to change at any time.
     */

    int getProperties(int ch) {
        char offset = (char)ch;
        int props = $$Lookup(offset);
        return props;
    }

    int getPropertiesEx(int ch) {
        char offset = (char)ch;
        int props = $$LookupEx(offset);
        return props;
    }

    @IntrinsicCandidate
    boolean isDigit(int ch) {
        return '0' <= ch && ch <= '9';
    }

    @IntrinsicCandidate
    boolean isLowerCase(int ch) {
        return (getPropertiesEx(ch) & $$maskOtherLowercase) != 0;
    }

    @IntrinsicCandidate
    boolean isUpperCase(int ch) {
        return (getPropertiesEx(ch) & $$maskOtherUppercase) != 0;
    }

    boolean isOtherAlphabetic(int ch) {
        int props = getPropertiesEx(ch);
        return (props & $$maskOtherAlphabetic) != 0;
    }

    boolean isIdeographic(int ch) {
        int props = getPropertiesEx(ch);
        return (props & $$maskIdeographic) != 0;
    }

    int getType(int ch) {
        int props = getProperties(ch);
        return (props & $$maskType);
    }

    boolean isJavaIdentifierStart(int ch) {
        int props = getProperties(ch);
        return ((props & $$maskIdentifierInfo) >= $$lowJavaStart);
    }

    boolean isJavaIdentifierPart(int ch) {
        int props = getProperties(ch);
        return ((props & $$nonzeroJavaPart) != 0);
    }

    boolean isUnicodeIdentifierStart(int ch) {
        return (getPropertiesEx(ch) & $$maskIDStart) != 0;
    }

    boolean isUnicodeIdentifierPart(int ch) {
        return (getPropertiesEx(ch) & $$maskIDContinue) != 0 ||
               isIdentifierIgnorable(ch);
    }

    boolean isIdentifierIgnorable(int ch) {
        int props = getProperties(ch);
        return ((props & $$maskIdentifierInfo) == $$valueIgnorable);
    }

    boolean isEmoji(int ch) {
        return (getPropertiesEx(ch) & $$maskEmoji) != 0;
    }

    boolean isEmojiPresentation(int ch) {
        return (getPropertiesEx(ch) & $$maskEmojiPresentation) != 0;
    }

    boolean isEmojiModifier(int ch) {
        return (getPropertiesEx(ch) & $$maskEmojiModifier) != 0;
    }

    boolean isEmojiModifierBase(int ch) {
        return (getPropertiesEx(ch) & $$maskEmojiModifierBase) != 0;
    }

    boolean isEmojiComponent(int ch) {
        return (getPropertiesEx(ch) & $$maskEmojiComponent) != 0;
    }

    boolean isExtendedPictographic(int ch) {
        return (getPropertiesEx(ch) & $$maskExtendedPictographic) != 0;
    }

    int toLowerCase(int ch) {
        if (ch < 'A') { // Fast path for low code points
            return ch;
        }
        // ASCII and Latin-1 were designed to optimize case-twiddling operations
        int lower = ch | 0x20;
        if (lower <= 'z' // In range a-z
                || (lower >= 0xE0 && lower <= 0xFE && lower != 0xF7)) { // ..or agrave-thorn, excluding division
            return lower;
        }
        return ch;
    }

    int toUpperCase(int ch) {
        if (ch < 'a') { // Fast path for low code points
            return ch;
        }
        // ASCII and Latin-1 were designed to optimize case-twiddling operations
        int upper = ch & 0xDF;
        if (upper <= 'Z' // In range A-Z
                || (upper >= 0xC0 && upper <= 0xDE && upper != 0xD7)) { // ..or Agrave-Thorn, not multiplication
            return upper;
        }

        // Special-case for 'y with Diaeresis' which uppercases out of latin1
        if (ch == 0xFF) {
            return 0x178; // Capital Letter Y with Diaeresis
        }
        // Special-case for 'Micro Sign' which uppercases out of latin1
        if (ch == 0xB5) {
            return 0x39C; // Greek Capital Letter Mu
        }
        return ch;
    }

    /**
     * Compares two latin1 code points, ignoring case considerations
     *
     * @param b1 byte representing a latin1 code point
     * @param b2 another byte representing a latin1 code point
     * @return true if the two bytes are considered equals ignoring case in latin1
     */
     static boolean equalsIgnoreCase(byte b1, byte b2) {
         if (b1 == b2) {
             return true;
         }
         // ASCII and Latin-1 were designed to optimize case-twiddling operations
         int upper = b1 & 0xDF;
         if (upper < 'A') {
             return false;  // Low ASCII
         }
         return (upper <= 'Z' // In range A-Z
                 || (upper >= 0xC0 && upper <= 0XDE && upper != 0xD7)) // ..or A-grave-Thorn, not multiplication
                 && upper == (b2 & 0xDF); // b2 has same uppercase
    }

    int toTitleCase(int ch) {
        return toUpperCase(ch);
    }

    // Digit values for codePoints in the 0-255 range. Contents generated using:
    // for (char i = 0; i < 256; i++) {
    //     int v = -1;
    //     if (i >= '0' && i <= '9') { v = i - '0'; } 
    //     else if (i >= 'A' && i <= 'Z') { v = i - 'A' + 10; }
    //     else if (i >= 'a' && i <= 'z') { v = i - 'a' + 10; }
    //     if (i % 20 == 0) System.out.println();
    //     System.out.printf("%2d, ", v);
    // }
    //
    // Analysis has shown that generating the whole array allows the JIT to generate
    // better code compared to a slimmed down array, such as one cutting off after 'z'
    @Stable
    private static final byte[] DIGITS = new byte[] {
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, -1, -1,
        -1, -1, -1, -1, -1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
        25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, -1, -1, -1, -1, -1, -1, 10, 11, 12,
        13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
        33, 34, 35, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 };

    int digit(int ch, int radix) {
        int value = DIGITS[ch];
        return (value >= 0 && value < radix && radix >= Character.MIN_RADIX
                && radix <= Character.MAX_RADIX) ? value : -1;
    }

    int getNumericValue(int ch) {
        int val = getProperties(ch);
        int retval = -1;

        switch (val & $$maskNumericType) {
            default: // cannot occur
            case ($$valueNotNumeric):         // not numeric
                retval = -1;
                break;
            case ($$valueDigit):              // simple numeric
                retval = ch + ((val & $$maskDigitOffset) >> $$shiftDigitOffset) & $$maskDigit;
                break;
            case ($$valueStrangeNumeric)      :       // "strange" numeric
                 retval = -2; 
                 break;
            case ($$valueJavaSupradecimal):           // Java supradecimal
                retval = (ch + ((val & $$maskDigitOffset) >> $$shiftDigitOffset) & $$maskDigit) + 10;
                break;
        }
        return retval;
    }

    @IntrinsicCandidate
    boolean isWhitespace(int ch) {
        int props = getProperties(ch);
        return ((props & $$maskIdentifierInfo) == $$valueJavaWhitespace);
    }

    byte getDirectionality(int ch) {
        int val = getProperties(ch);
        byte directionality = (byte)((val & $$maskBidi) >> $$shiftBidi);

        if (directionality == 0xF ) {
            directionality = -1;
        }
        return directionality;
    }

    boolean isMirrored(int ch) {
        int props = getProperties(ch);
        return ((props & $$maskMirrored) != 0);
    }

    int toUpperCaseEx(int ch) {
        int mapChar = ch;
        int val = getProperties(ch);

        if ((val & $$maskUpperCase) != 0) {
            if ((val & $$maskCaseOffset) != $$maskCaseOffset) {
                int offset = val  << $$shiftCaseOffsetSign >> ($$shiftCaseOffsetSign+$$shiftCaseOffset);
                mapChar =  ch - offset;
            }
            else {
                switch(ch) {
                    // map overflow characters
                    case 0x00B5 : mapChar = 0x039C; break;
                    default       : mapChar = Character.ERROR; break;
                }
            }
        }
        return mapChar;
    }

    @Stable
    static char[] sharpsMap = new char[] {'S', 'S'};

    char[] toUpperCaseCharArray(int ch) {
        char[] upperMap = {(char)ch};
        if (ch == 0x00DF) {
            upperMap = sharpsMap;
        }
        return upperMap;
    }

    static final CharacterDataLatin1 instance = new CharacterDataLatin1();
    private CharacterDataLatin1() {};

    $$Tables

    static {
        $$Initializers
    }
}