package org.djunits.quantity;
   
   import org.djunits.quantity.def.Quantity;
   import org.djunits.unit.AbstractUnit;
   import org.djunits.unit.UnitInterface;
   import org.djunits.unit.UnitRuntimeException;
   import org.djunits.unit.Unitless;
   import org.djunits.unit.Units;
   import org.djunits.unit.scale.IdentityScale;
  import org.djunits.unit.scale.LinearScale;
  import org.djunits.unit.scale.Scale;
  import org.djunits.unit.si.SIPrefix;
  import org.djunits.unit.si.SIPrefixes;
  import org.djunits.unit.si.SIUnit;
  import org.djunits.unit.system.UnitSystem;
  
  /**
   * Pressure is the force exerted per unit area, measured in pascals (Pa).
   * <p>
   * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See
   * for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
   * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
   * @author Alexander Verbraeck
   */
  public class Pressure extends Quantity<Pressure>
  {
      /** Constant with value zero. */
      public static final Pressure ZERO = ofSi(0.0);
  
      /** Constant with value one. */
      public static final Pressure ONE = ofSi(1.0);
  
      /** Constant with value NaN. */
      @SuppressWarnings("checkstyle:constantname")
      public static final Pressure NaN = ofSi(Double.NaN);
  
      /** Constant with value POSITIVE_INFINITY. */
      public static final Pressure POSITIVE_INFINITY = ofSi(Double.POSITIVE_INFINITY);
  
      /** Constant with value NEGATIVE_INFINITY. */
      public static final Pressure NEGATIVE_INFINITY = ofSi(Double.NEGATIVE_INFINITY);
  
      /** Constant with value MAX_VALUE. */
      public static final Pressure POS_MAXVALUE = ofSi(Double.MAX_VALUE);
  
      /** Constant with value -MAX_VALUE. */
      public static final Pressure NEG_MAXVALUE = ofSi(-Double.MAX_VALUE);
  
      /** */
      private static final long serialVersionUID = 600L;
  
      /**
       * Instantiate a Pressure quantity with an SI or base value and a display unit.
       * @param value the quantity value expressed in the SI or base unit
       * @param displayUnit the display unit to use
       * @param useSi use SI value when true, use value in unit when false
       */
      public Pressure(final double value, final Pressure.Unit displayUnit, final boolean useSi)
      {
          super(value, displayUnit, useSi);
      }
  
      /**
       * Instantiate a Pressure quantity expressed in the given unit.
       * @param valueInUnit the quantity value expressed in the given unit
       * @param unit the unit of the value, also acts as the display unit
       */
      public Pressure(final double valueInUnit, final Pressure.Unit unit)
      {
          this(valueInUnit, unit, false);
      }
  
      /**
       * Return a Pressure instance based on an SI value.
       * @param si the si value
       * @return the Pressure instance based on an SI value
       */
      public static Pressure ofSi(final double si)
      {
          return new Pressure(si, Pressure.Unit.SI, true);
      }
  
      /**
       * Instantiate a Pressure quantity with an SI or base value and a display unit.
       * @param siValue the quantity value expressed in the SI or base unit
       * @param displayUnit the display unit to use
       * @return the Pressure instance based on an SI value with the given display unit
       */
      public static Pressure ofSi(final double siValue, final Pressure.Unit displayUnit)
      {
          return new Pressure(siValue, displayUnit, true);
      }
  
      @Override
      public Pressure instantiateSi(final double siValue, final UnitInterface<Pressure> displayUnit)
      {
          return new Pressure(siValue, (Pressure.Unit) displayUnit, true);
      }
  
     /**
      * Returns a Pressure representation of a textual representation of a value with a unit. The String representation that can
      * be parsed is the double value in the unit, followed by a localized or English abbreviation of the unit. Spaces are
      * allowed, but not required, between the value and the unit.
      * @param text the textual representation to parse into a Pressure
      * @return the Scalar representation of the value in its unit
      * @throws IllegalArgumentException when the text cannot be parsed
      * @throws NullPointerException when the text argument is null
      */
     public static Pressure valueOf(final String text)
     {
         return Quantity.valueOf(text, ZERO);
     }
 
     /**
      * Returns a Pressure based on a value expressed in the unit.
      * @param valueInUnit the value, expressed in the given unit
      * @param unit the unit of the value, also acts as the display unit
      * @return ab Pressure representation of the value in its unit
      */
     public static Pressure of(final double valueInUnit, final Pressure.Unit unit)
     {
         return new Pressure(valueInUnit, unit);
     }
 
     /**
      * Returns a Pressure based on a value and the textual representation of the unit, which can be localized.
      * @param valueInUnit the value, expressed in the unit as given by unitString
      * @param unitString the textual representation of the unit
      * @return the Scalar representation of the value in its unit
      * @throws IllegalArgumentException when the unit cannot be parsed or is incorrect
      * @throws NullPointerException when the unitString argument is null
      */
     public static Pressure of(final double valueInUnit, final String unitString)
     {
         return Quantity.of(valueInUnit, unitString, ZERO);
     }
 
     @Override
     public Pressure.Unit getDisplayUnit()
     {
         return (Pressure.Unit) super.getDisplayUnit();
     }
 
     /**
      * Calculate the division of Pressure and Pressure, which results in a Dimensionless quantity.
      * @param v quantity
      * @return quantity as a division of Pressure and Pressure
      */
     public Dimensionless divide(final Pressure v)
     {
         return new Dimensionless(this.si() / v.si(), Unitless.BASE);
     }
 
     /**
      * Calculate the multiplication of Pressure and Area, which results in a Force scalar.
      * @param v scalar
      * @return scalar as a multiplication of Pressure and Area
      */
     public Force multiply(final Area v)
     {
         return new Force(this.si() * v.si(), Force.Unit.SI);
     }
 
     /**
      * Calculate the multiplication of Pressure and Volume, which results in a Energy scalar.
      * @param v scalar
      * @return scalar as a multiplication of Pressure and Volume
      */
     public Energy multiply(final Volume v)
     {
         return new Energy(this.si() * v.si(), Energy.Unit.SI);
     }
 
     /******************************************************************************************************/
     /********************************************** UNIT CLASS ********************************************/
     /******************************************************************************************************/
 
     /**
      * Pressure.Unit encodes the units of force exerted per unit area.
      * <p>
      * Copyright (c) 2025-2026 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved.
      * See for project information <a href="https://djunits.org" target="_blank">https://djunits.org</a>. The DJUNITS project is
      * distributed under a <a href="https://djunits.org/docs/license.html" target="_blank">three-clause BSD-style license</a>.
      * @author Alexander Verbraeck
      */
     @SuppressWarnings("checkstyle:constantname")
     public static class Unit extends AbstractUnit<Pressure>
     {
         /** The dimensions of pressure: kg/m.s2. */
         public static final SIUnit SI_UNIT = SIUnit.of("kg/ms2");
 
         /** Pascal. */
         public static final Pressure.Unit Pa =
                 new Pressure.Unit("Pa", "Pa", "pascal", IdentityScale.SCALE, UnitSystem.SI_DERIVED, SIPrefixes.getSiPrefix(""));
 
         /** The SI or BASE unit. */
         public static final Pressure.Unit SI = (Unit) Pa.generateSiPrefixes(false, false);
 
         /** hectopascal. */
         public static final Pressure.Unit hPa = Units.resolve(Pressure.Unit.class, "hPa");
 
         /** kilopascal. */
         public static final Pressure.Unit kPa = Units.resolve(Pressure.Unit.class, "kPa");
 
         /** standard atmosphere. */
         public static final Pressure.Unit atm = Pa.deriveUnit("atm", "atmosphere (standard)", 101325.0, UnitSystem.OTHER);
 
         /** torr. */
         public static final Pressure.Unit torr = atm.deriveUnit("torr", "Torr", 1.0 / 760.0, UnitSystem.OTHER);
 
         /** technical atmosphere = kgf/cm2. */
         public static final Pressure.Unit at =
                 Pa.deriveUnit("at", "atmosphere (technical)", Acceleration.Unit.CONST_GRAVITY / 1.0E-4, UnitSystem.OTHER);
 
         /** barye = dyne/cm2. */
         public static final Pressure.Unit Ba = Pa.deriveUnit("Ba", "barye", 1.0E-5 / 1.0E-4, UnitSystem.CGS);
 
         /** bar. */
         public static final Pressure.Unit bar = Pa.deriveUnit("bar", "bar", 1.0E5, UnitSystem.OTHER);
 
         /** millibar. */
         public static final Pressure.Unit mbar = bar.deriveUnit("mbar", "millibar", 1.0E-3, UnitSystem.OTHER);
 
         /** cm Hg. */
         public static final Pressure.Unit cmHg = Pa.deriveUnit("cmHg", "centimeter mercury", 1333.224, UnitSystem.OTHER);
 
         /** mm Hg. */
         public static final Pressure.Unit mmHg = Pa.deriveUnit("mmHg", "millimeter mercury", 133.3224, UnitSystem.OTHER);
 
         /** foot Hg. */
         public static final Pressure.Unit ftHg = Pa.deriveUnit("ftHg", "foot mercury", 40.63666E3, UnitSystem.IMPERIAL);
 
         /** inch Hg. */
         public static final Pressure.Unit inHg = Pa.deriveUnit("inHg", "inch mercury", 3.386389E3, UnitSystem.IMPERIAL);
 
         /** kilogram-force per square millimeter. */
         public static final Pressure.Unit kgf_mm2 = Pa.deriveUnit("kgf/mm2", "kilogram-force per square millimeter",
                 Acceleration.Unit.CONST_GRAVITY / 1.0E-6, UnitSystem.OTHER);
 
         /** pound-force per square foot. */
         public static final Pressure.Unit lbf_ft2 = Pa.deriveUnit("lbf/ft2", "pound-force per square foot",
                 Mass.Unit.CONST_LB * Acceleration.Unit.CONST_GRAVITY / (Length.Unit.CONST_FT * Length.Unit.CONST_FT),
                 UnitSystem.IMPERIAL);
 
         /** pound-force per square inch. */
         public static final Pressure.Unit lbf_in2 = Pa.deriveUnit("lbf/in2", "pound-force per square inch",
                 Mass.Unit.CONST_LB * Acceleration.Unit.CONST_GRAVITY / (Length.Unit.CONST_IN * Length.Unit.CONST_IN),
                 UnitSystem.IMPERIAL);
 
         /** psi = pound-force per square inch. */
         public static final Pressure.Unit psi = lbf_in2;
 
         /** pieze. */
         public static final Pressure.Unit pz = Pa.deriveUnit("pz", "pi\u00E8ze", 1000.0, UnitSystem.MTS);
 
         /**
          * Create a new Pressure unit.
          * @param id the id or main abbreviation of the unit
          * @param name the full name of the unit
          * @param scaleFactorToBaseUnit the scale factor of the unit to convert it TO the base (SI) unit
          * @param unitSystem the unit system such as SI or IMPERIAL
          */
         public Unit(final String id, final String name, final double scaleFactorToBaseUnit, final UnitSystem unitSystem)
         {
             super(id, name, scaleFactorToBaseUnit, unitSystem);
         }
 
         /**
          * Return a derived unit for this unit, with textual abbreviation(s) and a display abbreviation.
          * @param textualAbbreviation the textual abbreviation of the unit, which doubles as the id
          * @param displayAbbreviation the display abbreviation of the unit
          * @param name the full name of the unit
          * @param scale the scale to use to convert from this unit to the standard (e.g., SI, BASE) unit
          * @param unitSystem unit system, e.g. SI or Imperial
          * @param siPrefix the SI Prefix of this unit
          */
         public Unit(final String textualAbbreviation, final String displayAbbreviation, final String name, final Scale scale,
                 final UnitSystem unitSystem, final SIPrefix siPrefix)
         {
             super(textualAbbreviation, displayAbbreviation, name, scale, unitSystem, siPrefix);
         }
 
         @Override
         public SIUnit siUnit()
         {
             return SI_UNIT;
         }
 
         @Override
         public Unit getBaseUnit()
         {
             return SI;
         }
 
         @Override
         public Pressure ofSi(final double si, final UnitInterface<Pressure> displayUnit)
         {
             return new Pressure(si, (Unit) displayUnit, true);
         }
 
         @Override
         public Pressure.Unit deriveUnit(final String textualAbbreviation, final String displayAbbreviation, final String name,
                 final double scaleFactor, final UnitSystem unitSystem, final SIPrefix siPrefix)
         {
             if (getScale() instanceof LinearScale ls)
             {
                 return new Pressure.Unit(textualAbbreviation, displayAbbreviation, name,
                         new LinearScale(ls.getScaleFactorToBaseUnit() * scaleFactor), unitSystem, siPrefix);
             }
             throw new UnitRuntimeException("Only possible to derive a unit from a unit with a linear scale");
         }
 
         @Override
         public Pressure.Unit deriveUnit(final String abbreviation, final String name, final double scaleFactor,
                 final UnitSystem unitSystem)
         {
             return (Unit) super.deriveUnit(abbreviation, name, scaleFactor, unitSystem);
         }
 
     }
 
 }