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package com.oracle.truffle.js.runtime.doubleconv;

This class provides the public API for the double conversion package.
Using double-conversion version 3.1.5.
/**
 * This class provides the public API for the double conversion package.
 *
 * Using double-conversion version 3.1.5.
 */
public final class DoubleConversion {

    private DoubleConversion() {
        // should not be constructed
    }

    private static final int kMaxFixedDigitsBeforePoint = 60;
    private static final int kMaxFixedDigitsAfterPoint = 60;
    private static final int kMaxExponentialDigits = 120;
    private static final int kBase10MaximalLength = 17;

    
Converts a double number to its shortest string representation.
Params:
value – number to convert
Returns:
formatted number/**
     * Converts a double number to its shortest string representation.
     *
     * @param value number to convert
     * @return formatted number
     */
    public static String toShortest(final double value) {
        assert Double.isFinite(value) : value;

        final DtoaBuffer buffer = new DtoaBuffer(FastDtoa.kFastDtoaMaximalLength);
        dtoaShortest(value, buffer);

        return buffer.format(DtoaMode.SHORTEST, 0);
    }

    private static void dtoaShortest(final double value, final DtoaBuffer buffer) {
        final double absValue = Math.abs(value);

        if (value < 0) {
            buffer.isNegative = true;
        }

        if (value == 0) {
            buffer.append('0');
            buffer.decimalPoint = 1;
        } else if (!fastDtoaShortest(absValue, buffer)) {
            buffer.reset();
            bignumDtoa(absValue, DtoaMode.SHORTEST, 0, buffer);
        }
    }

    
Converts a double number to a string representation with a fixed number of digits after the
decimal point.
Params:
value – number to convert.
requestedDigits – number of digits after decimal point
Returns:
formatted number/**
     * Converts a double number to a string representation with a fixed number of digits after the
     * decimal point.
     *
     * @param value number to convert.
     * @param requestedDigits number of digits after decimal point
     * @return formatted number
     */
    public static String toFixed(final double value, final int requestedDigits) {
        assert Double.isFinite(value) : value;

        final DtoaBuffer buffer = new DtoaBuffer(kMaxFixedDigitsBeforePoint + kMaxFixedDigitsAfterPoint);
        final double absValue = Math.abs(value);

        if (value < 0) {
            buffer.isNegative = true;
        }

        if (value == 0) {
            buffer.append('0');
            buffer.decimalPoint = 1;
        } else if (!fixedDtoa(absValue, requestedDigits, buffer)) {
            buffer.reset();
            bignumDtoa(absValue, DtoaMode.FIXED, requestedDigits, buffer);
        }

        return buffer.format(DtoaMode.FIXED, requestedDigits);
    }

    
Converts a double number to a string representation with a fixed number of digits.
Params:
value – number to convert
precision – number of digits to create
Returns:
formatted number/**
     * Converts a double number to a string representation with a fixed number of digits.
     *
     * @param value number to convert
     * @param precision number of digits to create
     * @return formatted number
     */
    public static String toPrecision(final double value, final int precision) {
        assert Double.isFinite(value) : value;

        final DtoaBuffer buffer = new DtoaBuffer(precision);
        dtoaPrecision(value, precision, buffer);

        return buffer.format(DtoaMode.PRECISION, 0);
    }

    private static void dtoaPrecision(final double value, final int precision, final DtoaBuffer buffer) {
        final double absValue = Math.abs(value);

        if (value < 0) {
            buffer.isNegative = true;
        }

        if (value == 0) {
            for (int i = 0; i < precision; i++) {
                buffer.append('0');
            }
            buffer.decimalPoint = 1;

        } else if (!fastDtoaCounted(absValue, precision, buffer)) {
            buffer.reset();
            bignumDtoa(absValue, DtoaMode.PRECISION, precision, buffer);
        }
    }

    
Converts a double number to a string representation using the BignumDtoa algorithm and the specified conversion mode and number of digits. 
Params:
v – number to convert
mode – conversion mode
digits – number of digits
buffer – buffer to use/**
     * Converts a double number to a string representation using the {@code BignumDtoa} algorithm
     * and the specified conversion mode and number of digits.
     *
     * @param v number to convert
     * @param mode conversion mode
     * @param digits number of digits
     * @param buffer buffer to use
     */
    public static void bignumDtoa(final double v, final DtoaMode mode, final int digits, final DtoaBuffer buffer) {
        assert v > 0 && !Double.isNaN(v) && !Double.isInfinite(v) : v;

        BignumDtoa.bignumDtoa(v, mode, digits, buffer);
    }

    
Converts a double number to its shortest string representation using the FastDtoa algorithm. 
Params:
v – number to convert
buffer – buffer to use
Returns:
true if conversion succeeded/**
     * Converts a double number to its shortest string representation using the {@code FastDtoa}
     * algorithm.
     *
     * @param v number to convert
     * @param buffer buffer to use
     * @return true if conversion succeeded
     */
    public static boolean fastDtoaShortest(final double v, final DtoaBuffer buffer) {
        assert v > 0 && !Double.isNaN(v) && !Double.isInfinite(v) : v;

        return FastDtoa.grisu3(v, buffer);
    }

    
Converts a double number to a string representation with the given number of digits using the FastDtoa algorithm. 
Params:
v – number to convert
precision – number of digits to generate
buffer – buffer to use
Returns:
true if conversion succeeded/**
     * Converts a double number to a string representation with the given number of digits using the
     * {@code FastDtoa} algorithm.
     *
     * @param v number to convert
     * @param precision number of digits to generate
     * @param buffer buffer to use
     * @return true if conversion succeeded
     */
    public static boolean fastDtoaCounted(final double v, final int precision, final DtoaBuffer buffer) {
        assert v > 0 && !Double.isNaN(v) && !Double.isInfinite(v) : v;

        return FastDtoa.grisu3Counted(v, precision, buffer);
    }

    
Converts a double number to a string representation with a fixed number of digits after the decimal point using the FixedDtoa algorithm. 
Params:
v – number to convert.
digits – number of digits after the decimal point
buffer – buffer to use
Returns:
true if conversion succeeded/**
     * Converts a double number to a string representation with a fixed number of digits after the
     * decimal point using the {@code FixedDtoa} algorithm.
     *
     * @param v number to convert.
     * @param digits number of digits after the decimal point
     * @param buffer buffer to use
     * @return true if conversion succeeded
     */
    public static boolean fixedDtoa(final double v, final int digits, final DtoaBuffer buffer) {
        assert v > 0 && !Double.isNaN(v) && !Double.isInfinite(v) : v;

        return FixedDtoa.fastFixedDtoa(v, digits, buffer);
    }

    
Computes a representation in exponential format with requestedDigits after the decimal point.
The last emitted digit is rounded. If requestedDigits equals -1, then the shortest
exponential representation is computed.
Params:
value – number to convert
requestedDigits – number of digits after the decimal point
Returns:
true if conversion succeeded/**
     * Computes a representation in exponential format with requestedDigits after the decimal point.
     * The last emitted digit is rounded. If requestedDigits equals -1, then the shortest
     * exponential representation is computed.
     *
     * @param value number to convert
     * @param requestedDigits number of digits after the decimal point
     * @return true if conversion succeeded
     */
    public static String toExponential(double value, int requestedDigits) {
        return toExponential(value, requestedDigits, true);
    }

    
Computes a representation in exponential format with requestedDigits after the decimal point.
The last emitted digit is rounded. If requestedDigits equals -1, then the shortest
exponential representation is computed.
Params:
value – number to convert
requestedDigits – number of digits after the decimal point
uniqueZero – "-0.0" is converted to "0.0".
Returns:
true if conversion succeeded/**
     * Computes a representation in exponential format with requestedDigits after the decimal point.
     * The last emitted digit is rounded. If requestedDigits equals -1, then the shortest
     * exponential representation is computed.
     *
     * @param value number to convert
     * @param requestedDigits number of digits after the decimal point
     * @param uniqueZero "-0.0" is converted to "0.0".
     * @return true if conversion succeeded
     */
    public static String toExponential(double value, int requestedDigits, boolean uniqueZero) {
        assert Double.isFinite(value) : value;
        assert !(requestedDigits < -1 || requestedDigits > kMaxExponentialDigits) : requestedDigits;

        boolean sign = value < 0.0;
        double absValue = Math.abs(value);

        // Add space for digit before the decimal point.
        int kDecimalRepCapacity = kMaxExponentialDigits + 1;
        assert kDecimalRepCapacity > kBase10MaximalLength;
        final DtoaBuffer buffer = new DtoaBuffer(kDecimalRepCapacity);

        if (requestedDigits == -1) {
            dtoaShortest(absValue, buffer);
        } else {
            dtoaPrecision(absValue, requestedDigits + 1, buffer);
            assert buffer.getLength() <= requestedDigits + 1;

            for (int i = buffer.getLength(); i < requestedDigits + 1; ++i) {
                buffer.append('0');
            }
            assert buffer.getLength() == requestedDigits + 1;
        }

        StringBuilder resultBuilder = new StringBuilder();
        if (sign && (value != 0.0 || !uniqueZero)) {
            resultBuilder.append('-');
        }

        buffer.toExponentialFormat(resultBuilder);
        return resultBuilder.toString();
    }
}