package com.google.common.math;

import static com.google.common.base.Preconditions.checkArgument;
import static java.lang.Double.MAX_EXPONENT;
import static java.lang.Double.MIN_EXPONENT;
import static java.lang.Double.POSITIVE_INFINITY;
import static java.lang.Double.doubleToRawLongBits;
import static java.lang.Double.isNaN;
import static java.lang.Double.longBitsToDouble;
import static java.lang.Math.getExponent;
import static java.lang.Math.max;

   * {@code n == 0}, or {@code n!}, or {@link Double#POSITIVE_INFINITY} if {@code n! >
   * Double.MAX_VALUE}.
   *
   * <p>The result is within 1 ulp of the true value.
   *
   * @throws IllegalArgumentException if {@code n < 0}
   */
  public static double factorial(int n) {
    checkNonNegative("n", n);
    if (n > MAX_FACTORIAL) {
      return Double.POSITIVE_INFINITY;
    } else {

    checkTryParse(Double.POSITIVE_INFINITY, "Infinity");
    checkTryParse(Double.POSITIVE_INFINITY, "+Infinity");
    checkTryParse(Double.NEGATIVE_INFINITY, "-Infinity");
  }

  private static final String[] BAD_TRY_PARSE_INPUTS = {
    "",
    "+-",
    "+-0",
    " 5",
    "32 ",
    " 55 ",
    "infinity",
    "POSITIVE_INFINITY",
    "0x9A",
    "0x9A.bE-5",
    ".",

    checkTryParse(Double.POSITIVE_INFINITY, "Infinity");
    checkTryParse(Double.POSITIVE_INFINITY, "+Infinity");
    checkTryParse(Double.NEGATIVE_INFINITY, "-Infinity");
  }

  private static final String[] BAD_TRY_PARSE_INPUTS = {
    "",
    "+-",
    "+-0",
    " 5",
    "32 ",
    " 55 ",
    "infinity",
    "POSITIVE_INFINITY",
    "0x9A",
    "0x9A.bE-5",
    ".",

    checkTryParse(Float.POSITIVE_INFINITY, "Infinity");
    checkTryParse(Float.POSITIVE_INFINITY, "+Infinity");
    checkTryParse(Float.NEGATIVE_INFINITY, "-Infinity");
  }

  private static final String[] BAD_TRY_PARSE_INPUTS = {
    "",
    "+-",
    "+-0",
    " 5",
    "32 ",
    " 55 ",
    "infinity",
    "POSITIVE_INFINITY",
    "0x9A",
    "0x9A.bE-5",
    ".",

    checkTryParse(Float.POSITIVE_INFINITY, "Infinity");
    checkTryParse(Float.POSITIVE_INFINITY, "+Infinity");
    checkTryParse(Float.NEGATIVE_INFINITY, "-Infinity");
  }

  private static final String[] BAD_TRY_PARSE_INPUTS = {
    "",
    "+-",
    "+-0",
    " 5",
    "32 ",
    " 55 ",
    "infinity",
    "POSITIVE_INFINITY",
    "0x9A",
    "0x9A.bE-5",
    ".",

  public void testRoundInfiniteToIntAlwaysFails() {
    for (RoundingMode mode : ALL_ROUNDING_MODES) {
      assertThrows(
          ArithmeticException.class, () -> DoubleMath.roundToInt(Double.POSITIVE_INFINITY, mode));
      assertThrows(
          ArithmeticException.class, () -> DoubleMath.roundToInt(Double.NEGATIVE_INFINITY, mode));
    }
  }

  @GwtIncompatible // DoubleMath.roundToLong(double, RoundingMode)

  public void testRoundInfiniteToIntAlwaysFails() {
    for (RoundingMode mode : ALL_ROUNDING_MODES) {
      assertThrows(
          ArithmeticException.class, () -> DoubleMath.roundToInt(Double.POSITIVE_INFINITY, mode));
      assertThrows(
          ArithmeticException.class, () -> DoubleMath.roundToInt(Double.NEGATIVE_INFINITY, mode));
    }
  }

  @GwtIncompatible // DoubleMath.roundToLong(double, RoundingMode)

          return Double.MAX_VALUE * sign(x);
        case FLOOR:
          return (roundArbitrarily == Double.POSITIVE_INFINITY)
              ? Double.MAX_VALUE
              : Double.NEGATIVE_INFINITY;
        case CEILING:
          return (roundArbitrarily == Double.POSITIVE_INFINITY)
              ? Double.POSITIVE_INFINITY
              : -Double.MAX_VALUE;
        case UP:
          return roundArbitrarily;
        case UNNECESSARY:

    assertVerticalLinearTransformation(transformation, x);
  }

  public void testMapping_infiniteX1() {
    assertThrows(
        IllegalArgumentException.class,
        () -> LinearTransformation.mapping(Double.POSITIVE_INFINITY, 3.4));
  }

  public void testMapping_infiniteY1() {
    assertThrows(
        IllegalArgumentException.class,
        () -> LinearTransformation.mapping(1.2, Double.NEGATIVE_INFINITY));
  }