/*

 * Copyright (c) 1998, 2013, 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.

 *

 * 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * @test

 * @bug 4160406 4705734 4707389 6358355 7032154

 * @summary Tests for Float.parseFloat method

 */

import java.math.BigDecimal;

import java.math.BigInteger;

public class ParseFloat {

    private static final BigDecimal HALF = BigDecimal.valueOf(0.5);

    private static void fail(String val, float n) {

        throw new RuntimeException("Float.parseFloat failed. String:" +

                                                val + " Result:" + n);

    }

    private static void check(String val) {

        float n = Float.parseFloat(val);

        boolean isNegativeN = n < 0 || n == 0 && 1/n < 0;

        float na = Math.abs(n);

        String s = val.trim().toLowerCase();

        switch (s.charAt(s.length() - 1)) {

            case 'd':

            case 'f':

                s = s.substring(0, s.length() - 1);

                break;

        }

        boolean isNegative = false;

        if (s.charAt(0) == '+') {

            s = s.substring(1);

        } else if (s.charAt(0) == '-') {

            s = s.substring(1);

            isNegative = true;

        }

        if (s.equals("nan")) {

            if (!Float.isNaN(n)) {

                fail(val, n);

            }

            return;

        }

        if (Float.isNaN(n)) {

            fail(val, n);

        }

        if (isNegativeN != isNegative)

            fail(val, n);

        if (s.equals("infinity")) {

            if (na != Float.POSITIVE_INFINITY) {

                fail(val, n);

            }

            return;

        }

        BigDecimal bd;

        if (s.startsWith("0x")) {

            s = s.substring(2);

            int indP = s.indexOf('p');

            long exp = Long.parseLong(s.substring(indP + 1));

            int indD = s.indexOf('.');

            String significand;

            if (indD >= 0) {

                significand = s.substring(0, indD) + s.substring(indD + 1, indP);

                exp -= 4*(indP - indD - 1);

            } else {

                significand = s.substring(0, indP);

            }

            bd = new BigDecimal(new BigInteger(significand, 16));

            if (exp >= 0) {

                bd = bd.multiply(BigDecimal.valueOf(2).pow((int)exp));

            } else {

                bd = bd.divide(BigDecimal.valueOf(2).pow((int)-exp));

            }

        } else {

            bd = new BigDecimal(s);

        }

        BigDecimal l, u;

        if (Float.isInfinite(na)) {

            l = new BigDecimal(Float.MAX_VALUE).add(new BigDecimal(Math.ulp(Float.MAX_VALUE)).multiply(HALF));

            u = null;

        } else {

            l = new BigDecimal(na).subtract(new BigDecimal(Math.ulp(-Math.nextUp(-na))).multiply(HALF));

            u = new BigDecimal(na).add(new BigDecimal(Math.ulp(n)).multiply(HALF));

        }

        int cmpL = bd.compareTo(l);

        int cmpU = u != null ? bd.compareTo(u) : -1;

        if ((Float.floatToIntBits(n) & 1) != 0) {

            if (cmpL <= 0 || cmpU >= 0) {

                fail(val, n);

            }

        } else {

            if (cmpL < 0 || cmpU > 0) {

                fail(val, n);

            }

        }

    }

    private static void check(String val, float expected) {

        float n = Float.parseFloat(val);

        if (n != expected)

            fail(val, n);

        check(val);

    }

    private static void rudimentaryTest() {

        check(new String(""+Float.MIN_VALUE), Float.MIN_VALUE);

        check(new String(""+Float.MAX_VALUE), Float.MAX_VALUE);

        check("10",     (float)  10.0);

        check("10.0",   (float)  10.0);

        check("10.01",  (float)  10.01);

        check("-10",    (float) -10.0);

        check("-10.00", (float) -10.0);

        check("-10.01", (float) -10.01);

        // bug 6358355

        check("144115196665790480", 0x1.000002p57f);

        check("144115196665790481", 0x1.000002p57f);

        check("0.050000002607703203", 0.05f);

        check("0.050000002607703204", 0.05f);

        check("0.050000002607703205", 0.05f);

        check("0.050000002607703206", 0.05f);

        check("0.050000002607703207", 0.05f);

        check("0.050000002607703208", 0.05f);

        check("0.050000002607703209", 0.050000004f);

    }

    static  String badStrings[] = {

        "",

        "+",

        "-",

        "+e",

        "-e",

        "+e170",

        "-e170",

        // Make sure intermediate white space is not deleted.

        "1234   e10",

        "-1234   e10",

        // Control characters in the interior of a string are not legal

        "1\u0007e1",

        "1e\u00071",

        // NaN and infinity can't have trailing type suffices or exponents

        "NaNf",

        "NaNF",

        "NaNd",

        "NaND",

        "-NaNf",

        "-NaNF",

        "-NaNd",

        "-NaND",

        "+NaNf",

        "+NaNF",

        "+NaNd",

        "+NaND",

        "Infinityf",

        "InfinityF",

        "Infinityd",

        "InfinityD",

        "-Infinityf",

        "-InfinityF",

        "-Infinityd",

        "-InfinityD",

        "+Infinityf",

        "+InfinityF",

        "+Infinityd",

        "+InfinityD",

        "NaNe10",

        "-NaNe10",

        "+NaNe10",

        "Infinitye10",

        "-Infinitye10",

        "+Infinitye10",

        // Non-ASCII digits are not recognized

        "\u0661e\u0661", // 1e1 in Arabic-Indic digits

        "\u06F1e\u06F1", // 1e1 in Extended Arabic-Indic digits

        "\u0967e\u0967" // 1e1 in Devanagari digits

    };

    static String goodStrings[] = {

        "NaN",

        "+NaN",

        "-NaN",

        "Infinity",

        "+Infinity",

        "-Infinity",

        "1.1e-23f",

        ".1e-23f",

        "1e-23",

        "1f",

        "1",

        "2",

        "1234",

        "-1234",

        "+1234",

        "2147483647",   // Integer.MAX_VALUE

        "2147483648",

        "-2147483648",  // Integer.MIN_VALUE

        "-2147483649",

        "16777215",

        "16777216",     // 2^24

        "16777217",

        "-16777215",

        "-16777216",    // -2^24

        "-16777217",

        "9007199254740991",

        "9007199254740992",     // 2^53

        "9007199254740993",

        "-9007199254740991",

        "-9007199254740992",    // -2^53

        "-9007199254740993",

        "9223372036854775807",

        "9223372036854775808",  // Long.MAX_VALUE

        "9223372036854775809",

        "-9223372036854775808",

        "-9223372036854775809", // Long.MIN_VALUE

        "-9223372036854775810"

    };

    static String paddedBadStrings[];

    static String paddedGoodStrings[];

    static {

        String pad = " \t\n\r\f\u0001\u000b\u001f";

        paddedBadStrings = new String[badStrings.length];

        for(int i = 0 ; i <  badStrings.length; i++)

            paddedBadStrings[i] = pad + badStrings[i] + pad;

        paddedGoodStrings = new String[goodStrings.length];

        for(int i = 0 ; i <  goodStrings.length; i++)

            paddedGoodStrings[i] = pad + goodStrings[i] + pad;

    }

    /*

     * Throws an exception if <code>Input</code> is

     * <code>exceptionalInput</code> and {@link Float.parseFloat

     * parseFloat} does <em>not</em> throw an exception or if

     * <code>Input</code> is not <code>exceptionalInput</code> and

     * <code>parseFloat</code> throws an exception.  This method does

     * not attempt to test whether the string is converted to the

     * proper value; just whether the input is accepted appropriately

     * or not.

     */

    private static void testParsing(String [] input,

                                    boolean exceptionalInput) {

        for(int i = 0; i < input.length; i++) {

            double d;

            try {

                d = Float.parseFloat(input[i]);

                check(input[i]);

            }

            catch (NumberFormatException e) {

                if (! exceptionalInput) {

                    throw new RuntimeException("Float.parseFloat rejected " +

                                               "good string `" + input[i] +

                                               "'.");

                }

                break;

            }

            if (exceptionalInput) {

                throw new RuntimeException("Float.parseFloat accepted " +

                                           "bad string `" + input[i] +

                                           "'.");

            }

        }

    }

    /**

     * For each power of two, test at boundaries of

     * region that should convert to that value.

     */

    private static void testPowers() {

        for(int i = -149; i <= +127; i++) {

            float f = Math.scalb(1.0f, i);

            BigDecimal f_BD = new BigDecimal(f);

            BigDecimal lowerBound = f_BD.subtract(new BigDecimal(Math.ulp(-Math.nextUp(-f))).multiply(HALF));

            BigDecimal upperBound = f_BD.add(new BigDecimal(Math.ulp(f)).multiply(HALF));

            check(lowerBound.toString());

            check(upperBound.toString());

        }

        check(new BigDecimal(Float.MAX_VALUE).add(new BigDecimal(Math.ulp(Float.MAX_VALUE)).multiply(HALF)).toString());

    }

    public static void main(String[] args) throws Exception {

        rudimentaryTest();

        testParsing(goodStrings, false);

        testParsing(paddedGoodStrings, false);

        testParsing(badStrings, true);

        testParsing(paddedBadStrings, true);

        testPowers();

    }

}