//============================================================================
//ZedGraph Class Library - A Flexible Line Graph/Bar Graph Library in C#
//Copyright © 2005  John Champion
//
//This library is free software; you can redistribute it and/or
//modify it under the terms of the GNU Lesser General Public
//License as published by the Free Software Foundation; either
//version 2.1 of the License, or (at your option) any later version.
//
//This library 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
//Lesser General Public License for more details.
//
//You should have received a copy of the GNU Lesser General Public
//License along with this library; if not, write to the Free Software
//Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//=============================================================================

using System;
using System.Collections;
using System.Text;
using System.Drawing;
using System.Runtime.Serialization;
using System.Security.Permissions;

namespace ZedGraph
{
	/// <summary>
	/// The LogScale class inherits from the <see cref="Scale" /> class, and implements
	/// the features specific to <see cref="AxisType.Log" />.
	/// </summary>
	/// <remarks>
	/// LogScale is a non-linear axis in which the values are scaled using the base 10
	/// <see cref="Math.Log(double)" />
	/// function.
	/// </remarks>
	/// 
	/// <author> John Champion  </author>
	/// <version> $Revision: 1.12 $ $Date: 2007/04/16 00:03:02 $ </version>
	[Serializable]
	class LogScale : Scale, ISerializable //, ICloneable
	{

	#region constructors

		/// <summary>
		/// Default constructor that defines the owner <see cref="Axis" />
		/// (containing object) for this new object.
		/// </summary>
		/// <param name="owner">The owner, or containing object, of this instance</param>
		public LogScale( Axis owner )
			: base( owner )
		{
		}

		/// <summary>
		/// The Copy Constructor
		/// </summary>
		/// <param name="rhs">The <see cref="LogScale" /> object from which to copy</param>
		/// <param name="owner">The <see cref="Axis" /> object that will own the
		/// new instance of <see cref="LogScale" /></param>
		public LogScale( Scale rhs, Axis owner )
			: base( rhs, owner )
		{
		}

		/// <summary>
		/// Create a new clone of the current item, with a new owner assignment
		/// </summary>
		/// <param name="owner">The new <see cref="Axis" /> instance that will be
		/// the owner of the new Scale</param>
		/// <returns>A new <see cref="Scale" /> clone.</returns>
		public override Scale Clone( Axis owner )
		{
			return new LogScale( this, owner );
		}

	#endregion

	#region properties

		/// <summary>
		/// Return the <see cref="AxisType" /> for this <see cref="Scale" />, which is
		/// <see cref="AxisType.Log" />.
		/// </summary>
		public override AxisType Type
		{
			get { return AxisType.Log; }
		}

		/// <summary>
		/// Gets or sets the minimum value for this scale.
		/// </summary>
		/// <remarks>
		/// The set property is specifically adapted for <see cref="AxisType.Log" /> scales,
		/// in that it automatically limits the setting to values greater than zero.
		/// </remarks>
		public override double Min
		{
			get { return _min; }
			set { if ( value > 0 ) _min = value; }
		}

		/// <summary>
		/// Gets or sets the maximum value for this scale.
		/// </summary>
		/// <remarks>
		/// The set property is specifically adapted for <see cref="AxisType.Log" /> scales,
		/// in that it automatically limits the setting to values greater than zero.
		/// <see cref="XDate" /> struct.
		/// </remarks>
		public override double Max
		{
			get { return _max; }
			set { if ( value > 0 ) _max = value; }
		}

	#endregion

	#region methods

		/// <summary>
		/// Setup some temporary transform values in preparation for rendering the <see cref="Axis"/>.
		/// </summary>
		/// <remarks>
		/// This method is typically called by the parent <see cref="GraphPane"/>
		/// object as part of the <see cref="GraphPane.Draw"/> method.  It is also
		/// called by <see cref="GraphPane.GeneralTransform(double,double,CoordType)"/> and
		/// <see cref="GraphPane.ReverseTransform( PointF, out double, out double )"/>
		/// methods to setup for coordinate transformations.
		/// </remarks>
		/// <param name="pane">
		/// A reference to the <see cref="GraphPane"/> object that is the parent or
		/// owner of this object.
		/// </param>
		/// <param name="axis">
		/// The parent <see cref="Axis" /> for this <see cref="Scale" />
		/// </param>
		override public void SetupScaleData( GraphPane pane, Axis axis )
		{
			base.SetupScaleData( pane, axis );

			_minLinTemp = Linearize( _min );
			_maxLinTemp = Linearize( _max );
		}

		/// <summary>
		/// Convert a value to its linear equivalent for this type of scale.
		/// </summary>
		/// <remarks>
		/// The default behavior is to just return the value unchanged.  However,
		/// for <see cref="AxisType.Log" /> and <see cref="AxisType.Exponent" />,
		/// it returns the log or power equivalent.
		/// </remarks>
		/// <param name="val">The value to be converted</param>
		override public double Linearize( double val )
		{
			return SafeLog( val );
		}

		/// <summary>
		/// Convert a value from its linear equivalent to its actual scale value
		/// for this type of scale.
		/// </summary>
		/// <remarks>
		/// The default behavior is to just return the value unchanged.  However,
		/// for <see cref="AxisType.Log" /> and <see cref="AxisType.Exponent" />,
		/// it returns the anti-log or inverse-power equivalent.
		/// </remarks>
		/// <param name="val">The value to be converted</param>
		override public double DeLinearize( double val )
		{
			return Math.Pow( 10.0, val );
		}

		/// <summary>
		/// Determine the value for any major tic.
		/// </summary>
		/// <remarks>
		/// This method properly accounts for <see cref="Scale.IsLog"/>, <see cref="Scale.IsText"/>,
		/// and other axis format settings.
		/// </remarks>
		/// <param name="baseVal">
		/// The value of the first major tic (floating point double)
		/// </param>
		/// <param name="tic">
		/// The major tic number (0 = first major tic).  For log scales, this is the actual power of 10.
		/// </param>
		/// <returns>
		/// The specified major tic value (floating point double).
		/// </returns>
		override internal double CalcMajorTicValue( double baseVal, double tic )
		{
			return baseVal + (double)tic * CyclesPerStep;

		//	double val = baseVal + (double)tic * CyclesPerStep;
		//	double frac = val - Math.Floor( val );
		}

		/// <summary>
		/// Determine the value for any minor tic.
		/// </summary>
		/// <remarks>
		/// This method properly accounts for <see cref="Scale.IsLog"/>, <see cref="Scale.IsText"/>,
		/// and other axis format settings.
		/// </remarks>
		/// <param name="baseVal">
		/// The value of the first major tic (floating point double).  This tic value is the base
		/// reference for all tics (including minor ones).
		/// </param>
		/// <param name="iTic">
		/// The major tic number (0 = first major tic).  For log scales, this is the actual power of 10.
		/// </param>
		/// <returns>
		/// The specified minor tic value (floating point double).
		/// </returns>
		override internal double CalcMinorTicValue( double baseVal, int iTic )
		{
			double[] dLogVal = { 0, 0.301029995663981, 0.477121254719662, 0.602059991327962,
									0.698970004336019, 0.778151250383644, 0.845098040014257,
									0.903089986991944, 0.954242509439325, 1 };

			return baseVal + Math.Floor( (double) iTic / 9.0 ) + dLogVal[( iTic + 9 ) % 9];
		}

		/// <summary>
		/// Internal routine to determine the ordinals of the first minor tic mark
		/// </summary>
		/// <param name="baseVal">
		/// The value of the first major tic for the axis.
		/// </param>
		/// <returns>
		/// The ordinal position of the first minor tic, relative to the first major tic.
		/// This value can be negative (e.g., -3 means the first minor tic is 3 minor step
		/// increments before the first major tic.
		/// </returns>
		override internal int CalcMinorStart( double baseVal )
		{
			return -9;
		}

		/// <summary>
		/// Determine the value for the first major tic.
		/// </summary>
		/// <remarks>
		/// This is done by finding the first possible value that is an integral multiple of
		/// the step size, taking into account the date/time units if appropriate.
		/// This method properly accounts for <see cref="Scale.IsLog"/>, <see cref="Scale.IsText"/>,
		/// and other axis format settings.
		/// </remarks>
		/// <returns>
		/// First major tic value (floating point double).
		/// </returns>
		override internal double CalcBaseTic()
		{
			if ( _baseTic != PointPair.Missing )
				return _baseTic;
			else
			{
				// go to the nearest even multiple of the step size
				return Math.Ceiling( Scale.SafeLog( _min ) - 0.00000001 );
			}

		}
		
		/// <summary>
		/// Internal routine to determine the ordinals of the first and last major axis label.
		/// </summary>
		/// <returns>
		/// This is the total number of major tics for this axis.
		/// </returns>
		override internal int CalcNumTics()
		{
			int nTics = 1;

			//iStart = (int) ( Math.Ceiling( SafeLog( this.min ) - 1.0e-12 ) );
			//iEnd = (int) ( Math.Floor( SafeLog( this.max ) + 1.0e-12 ) );

			//nTics = (int)( ( Math.Floor( Scale.SafeLog( _max ) + 1.0e-12 ) ) -
			//		( Math.Ceiling( Scale.SafeLog( _min ) - 1.0e-12 ) ) + 1 ) / CyclesPerStep;
			nTics = (int)( ( Scale.SafeLog( _max ) - Scale.SafeLog( _min ) ) / CyclesPerStep ) + 1;

			if ( nTics < 1 )
				nTics = 1;
			else if ( nTics > 1000 )
				nTics = 1000;

			return nTics;
		}

		private double CyclesPerStep
		{
			//get { return (int)Math.Max( Math.Floor( Scale.SafeLog( _majorStep ) ), 1 ); }
			get { return _majorStep; }
		}

		/// <summary>
		/// Select a reasonable base 10 logarithmic axis scale given a range of data values.
		/// </summary>
		/// <remarks>
		/// This method only applies to <see cref="AxisType.Log"/> type axes, and it
		/// is called by the general <see cref="PickScale"/> method.  The scale range is chosen
		/// based always on powers of 10 (full log cycles).  This
		/// method honors the <see cref="Scale.MinAuto"/>, <see cref="Scale.MaxAuto"/>,
		/// and <see cref="Scale.MajorStepAuto"/> autorange settings.
		/// In the event that any of the autorange settings are false, the
		/// corresponding <see cref="Scale.Min"/>, <see cref="Scale.Max"/>, or <see cref="Scale.MajorStep"/>
		/// setting is explicitly honored, and the remaining autorange settings (if any) will
		/// be calculated to accomodate the non-autoranged values.  For log axes, the MinorStep
		/// value is not used.
		/// <para>On Exit:</para>
		/// <para><see cref="Scale.Min"/> is set to scale minimum (if <see cref="Scale.MinAuto"/> = true)</para>
		/// <para><see cref="Scale.Max"/> is set to scale maximum (if <see cref="Scale.MaxAuto"/> = true)</para>
		/// <para><see cref="Scale.MajorStep"/> is set to scale step size (if <see cref="Scale.MajorStepAuto"/> = true)</para>
		/// <para><see cref="Scale.Mag"/> is set to a magnitude multiplier according to the data</para>
		/// <para><see cref="Scale.Format"/> is set to the display format for the values (this controls the
		/// number of decimal places, whether there are thousands separators, currency types, etc.)</para>
		/// </remarks>
		/// <param name="pane">A reference to the <see cref="GraphPane"/> object
		/// associated with this <see cref="Axis"/></param>
		/// <param name="g">
		/// A graphic device object to be drawn into.  This is normally e.Graphics from the
		/// PaintEventArgs argument to the Paint() method.
		/// </param>
		/// <param name="scaleFactor">
		/// The scaling factor to be used for rendering objects.  This is calculated and
		/// passed down by the parent <see cref="GraphPane"/> object using the
		/// <see cref="PaneBase.CalcScaleFactor"/> method, and is used to proportionally adjust
		/// font sizes, etc. according to the actual size of the graph.
		/// </param>
		/// <seealso cref="PickScale"/>
		/// <seealso cref="AxisType.Log"/>
		override public void PickScale( GraphPane pane, Graphics g, float scaleFactor )
		{
			// call the base class first
			base.PickScale( pane, g, scaleFactor );

			// Majorstep is always 1 for log scales
			if ( _majorStepAuto )
				_majorStep = 1.0;

			_mag = 0;		// Never use a magnitude shift for log scales
			//this.numDec = 0;		// The number of decimal places to display is not used

			// Check for bad data range
			if ( _min <= 0.0 && _max <= 0.0 )
			{
				_min = 1.0;
				_max = 10.0;
			}
			else if ( _min <= 0.0 )
			{
				_min = _max / 10.0;
			}
			else if ( _max <= 0.0 )
			{
				_max = _min * 10.0;
			}

			// Test for trivial condition of range = 0 and pick a suitable default
			if ( _max - _min < 1.0e-20 )
			{
				if ( _maxAuto )
					_max = _max * 2.0;
				if ( _minAuto )
					_min = _min / 2.0;
			}

			// Get the nearest power of 10 (no partial log cycles allowed)
			if ( _minAuto )
				_min = Math.Pow( (double) 10.0,
					Math.Floor( Math.Log10( _min ) ) );
			if ( _maxAuto )
				_max = Math.Pow( (double) 10.0,
					Math.Ceiling( Math.Log10( _max ) ) );

		}

		/// <summary>
		/// Make a value label for an <see cref="AxisType.Log" /> <see cref="Axis" />.
		/// </summary>
		/// <param name="pane">
		/// A reference to the <see cref="GraphPane"/> object that is the parent or
		/// owner of this object.
		/// </param>
		/// <param name="index">
		/// The zero-based, ordinal index of the label to be generated.  For example, a value of 2 would
		/// cause the third value label on the axis to be generated.
		/// </param>
		/// <param name="dVal">
		/// The numeric value associated with the label.  This value is ignored for log (<see cref="Scale.IsLog"/>)
		/// and text (<see cref="Scale.IsText"/>) type axes.
		/// </param>
		/// <returns>The resulting value label as a <see cref="string" /></returns>
		override internal string MakeLabel( GraphPane pane, int index, double dVal )
		{
			if ( _format == null )
				_format = Scale.Default.Format;

			if ( _isUseTenPower )
				return string.Format( "{0:F0}", dVal );
			else
				return Math.Pow( 10.0, dVal ).ToString( _format );
		}

	#endregion

	#region Serialization
		/// <summary>
		/// Current schema value that defines the version of the serialized file
		/// </summary>
		public const int schema2 = 10;

		/// <summary>
		/// Constructor for deserializing objects
		/// </summary>
		/// <param name="info">A <see cref="SerializationInfo"/> instance that defines the serialized data
		/// </param>
		/// <param name="context">A <see cref="StreamingContext"/> instance that contains the serialized data
		/// </param>
		protected LogScale( SerializationInfo info, StreamingContext context ) : base( info, context )
		{
			// The schema value is just a file version parameter.  You can use it to make future versions
			// backwards compatible as new member variables are added to classes
			int sch = info.GetInt32( "schema2" );

		}
		/// <summary>
		/// Populates a <see cref="SerializationInfo"/> instance with the data needed to serialize the target object
		/// </summary>
		/// <param name="info">A <see cref="SerializationInfo"/> instance that defines the serialized data</param>
		/// <param name="context">A <see cref="StreamingContext"/> instance that contains the serialized data</param>
		[SecurityPermissionAttribute(SecurityAction.Demand,SerializationFormatter=true)]
		public override void GetObjectData( SerializationInfo info, StreamingContext context )
		{
			base.GetObjectData( info, context );
			info.AddValue( "schema2", schema2 );
		}
	#endregion

	}
}