using System;

namespace Science.Physics.GeneralPhysics
{
	/// <summary>
	/// Fluid
	/// </summary>
	public class Fluid
	{
		private Density rho;
		public Fluid(Density rho)
		{			
			this.rho = rho;
		}
		public Force BuoyantForce(Volume V)
		{
			Force f = new Force();
			f.Z = rho.kgPERmCUBE*V.mCUBE*Constant.AccelerationOfGravity;
			return f;
		}
		public Pressure PressureAtDepth(Length h)
		{
			Pressure p = new Pressure();
			p.Pa = p.Atmosphere + rho.kgPERmCUBE*Constant.AccelerationOfGravity*h.m;
			return p;
		}
		public void SolveBernoulliEquation(Velocity v1, Length h1, Pressure P1, 
			Velocity v2, Length h2, Pressure P2)
		{		
			double sum = 0.0;
			if(!v1.XVariableQ) sum+=0.5*rho.kgPERmCUBE*v1.X*v1.X;
			if(!v1.YVariableQ) sum+=0.5*rho.kgPERmCUBE*v1.Y*v1.Y;
			if(!v1.ZVariableQ) sum+=0.5*rho.kgPERmCUBE*v1.Z*v1.Z;
			if(!h1.VariableQ) sum+=rho.kgPERmCUBE*Constant.AccelerationOfGravity*h1.m;
			if(!P1.VariableQ) sum+=P1.Pa;
			if(!v2.XVariableQ) sum-=0.5*rho.kgPERmCUBE*v2.X*v2.X;
			if(!v2.YVariableQ) sum-=0.5*rho.kgPERmCUBE*v2.Y*v2.Y;
			if(!v2.ZVariableQ) sum-=0.5*rho.kgPERmCUBE*v2.Z*v2.Z;
			if(!h2.VariableQ) sum-=rho.kgPERmCUBE*Constant.AccelerationOfGravity*h2.m;
			if(!P2.VariableQ) sum-=P2.Pa;

			if(v1.XVariableQ) v1.X = Math.Sqrt(2.0/rho.kgPERmCUBE*(-sum));
			if(v1.YVariableQ) v1.Y = Math.Sqrt(2.0/rho.kgPERmCUBE*(-sum));
			if(v1.ZVariableQ) v1.Z = Math.Sqrt(2.0/rho.kgPERmCUBE*(-sum));
			if(h1.VariableQ) h1.m = -sum/rho.kgPERmCUBE/Constant.AccelerationOfGravity;
			if(P1.VariableQ) P1.Pa = -sum;
			if(v2.XVariableQ) v2.X = Math.Sqrt(2.0/rho.kgPERmCUBE*sum);
			if(v2.YVariableQ) v2.Y = Math.Sqrt(2.0/rho.kgPERmCUBE*sum);
			if(v2.ZVariableQ) v2.Z = Math.Sqrt(2.0/rho.kgPERmCUBE*sum);
			if(h2.VariableQ) h2.m = sum/rho.kgPERmCUBE/Constant.AccelerationOfGravity;
			if(P2.VariableQ) P2.Pa = sum;
		}
	}
}