coding UTF-8;

import Math;
import Text;
import GUI;
import File;
import tool.Graph3D;


/** The default value of the expression z(x,y) to plot graph */
const string DEFAULT_Z_EXPRESSION = "sin(2*x) + cos(2*y)";

/** The default value of the maximum value of the x-range of the graph. */
const string DEFAULT_X_MAX = "1.0";

/** The default value of the minimum value of the x-range of the graph. */
const string DEFAULT_X_MIN = "-1.0";

/** The default value of the number of the point toward x-direction of the mesh. */
const string DEFAULT_X_N = "80";

/** The default value of the maximum value of the y-range of the graph. */
const string DEFAULT_Y_MAX = "1.0";

/** The default value of the minimum value of the y-range of the graph. */
const string DEFAULT_Y_MIN = "-1.0";

/** The default value of the number of the point toward y-direction of the mesh. */
const string DEFAULT_Y_N = "80";


// Followings  are variables to store IDs of the graph and GUI components.

/** Stores the ID of the graph. **/
int graph = NULL;

/** Stores the ID of the input-window. **/
int window = NULL;

/** Stores the ID of the text-field of the expression z(x,y). **/
int expressionField = NULL;

/** Stores the ID of the text-field of the maximum value of x-range. **/
int xMaxField = NULL;

/** Stores the ID of the text-field of the minimum value of x-range. **/
int xMinField = NULL;

/** Stores the value of the number of the point toward x-direction of the mesh. */
int xNField = NULL;

/** Stores the ID of the text-field of the maximum value of y-range. **/
int yMaxField = NULL;

/** Stores the ID of the text-field of the minimum value of y-range. **/
int yMinField = NULL;

/** Stores the value of the number of the point toward y-direction of the mesh. */
int yNField = NULL;

/** Stores the ID of the PLOT button. **/
int plotButton = NULL;

/** Stores the ID of the CLEAR button. **/
int clearButton = NULL;

/** Stores the ID of the EXPORT button. **/
int exportButton = NULL;

/** Stores the ID of the EXIT button. **/
int exitButton = NULL;



/**
 * Invoked automatically when this program have started.
 */
void main(){

	// Set the console window invisible because it is not necessary for GUI program.
	hide();

	// Create (or get from the system) a 3D graph window.
	graph = getGraph3D();

	// Set the size and the location of the graph-window.
	setGraph3DLocation(graph, 350, 0);
	setGraph3DSize(graph, 720, 600);

	// Set options of the graph
	setGraph3DOption( graph, "WITH_POINTS", false );
	setGraph3DOption( graph, "WITH_LINES", false );
	setGraph3DOption( graph, "WITH_MEMBRANES", true );
	setGraph3DOption( graph, "WITH_MESHES", false );

	// Create and launch the input-window.
	createInputWindow();

	// If you want to read processings after when the user click PLOT button, 
	// see "onButtonClick" function at near the bottom of this code.
}


/**
 * Plots the expression to the 3D graph.
 * 
 * @param zExpression   The expression of z(x,y).
 * @param xMin   The minimum value of x-range.
 * @param xMax   The maximum value of x-range.
 * @param xN   The number of points toward x-direction of the mesh.
 * @param xMin   The minimum value of y-range.
 * @param xMax   The maximum value of y-range.
 * @param yN   The number of points toward y-direction of the mesh.
 */
void plotGraph( string zExpression, double xMin, double xMax, int xN, double yMin, double yMax, int yN ){

	// Arrays storing vertices data to transfer the graph.
	double xArray[yN][xN];
	double yArray[yN][xN];
	double zArray[yN][xN];

	// coordinate variables of a point.
	double x;
	double y;
	double z;

	// Check the syntax of the expression z(x,y).
	if( !evaluable(zExpression, 0.0) ){
		alert("The form of the expression of \"z(x,y)\" is wrong.");
		return;
	}

	// Store coordinate values to arrays at lattice points
	// (xN-1 and yN-1 equally divided points of the x-range and y-range)
	float dx = (xMax-xMin)/(xN-1);
	float dy = (yMax-yMin)/(yN-1);
	for( int xi=0; xi<xN; xi++ ){
		for( int yi=0; yi<yN; yi++ ){
			x = xMin + xi * dx;
			y = yMin + yi * dy;

			// Evaluate the value of z(x,y). (The second argument is an option to get the value of float type)
			z = feval( zExpression, 0.0 );

			xArray[ yi ][ xi ] = x;
			yArray[ yi ][ xi ] = y;
			zArray[ yi ][ xi ] = z;
		}
	}

	// Transfer arrays to the graph, and plot it.
	addGraph3DData( graph, xArray, yArray, zArray );
}


/**
 * Creates GUI components of the input-window and launch it.
 */
void createInputWindow(){

	int leftWidth = 100;
	int rightX = leftWidth + 10;
	int rightWidth = 190;
	int buttonWidth = 290;
	int fontSize = 20;

	window = newWindow( 0, 0, 340, 450, "Input Window" );

	int expressionLabel = newTextLabel( 10, 10, leftWidth, 25, "z(x,y) =" );
	setComponentFontSize(expressionLabel, fontSize);
	mountComponent( expressionLabel, window );

	expressionField = newTextField( rightX, 10, rightWidth, 25, DEFAULT_Z_EXPRESSION );
	setComponentFontSize(expressionField, fontSize);
	mountComponent( expressionField, window );


	int lowX = 10;
	int columnWidth = 70;

	int xMaxLabel = newTextLabel( lowX, 60, columnWidth, 25, "x-max" );
	setComponentFontSize(xMaxLabel, fontSize);
	mountComponent( xMaxLabel, window );

	xMaxField = newTextField( lowX+columnWidth, 60, columnWidth, 25, DEFAULT_X_MAX );
	setComponentFontSize(xMaxField, fontSize);
	mountComponent( xMaxField, window );

	int xMinLabel = newTextLabel( lowX, 90, columnWidth, 25, "x-min" );
	setComponentFontSize(xMinLabel, fontSize);
	mountComponent( xMinLabel, window );

	xMinField = newTextField( lowX+columnWidth, 90, columnWidth, 25, DEFAULT_X_MIN );
	setComponentFontSize(xMinField, fontSize);
	mountComponent( xMinField, window );

	int xNLabel = newTextLabel( lowX, 120, columnWidth, 25, "x-N" );
	setComponentFontSize(xNLabel, fontSize);
	mountComponent( xNLabel, window );

	xNField = newTextField( lowX+columnWidth, 120, columnWidth, 25, DEFAULT_X_N );
	setComponentFontSize(xNField, fontSize);
	mountComponent( xNField, window );


	lowX = 160;
	columnWidth = 70;

	int yMaxLabel = newTextLabel( lowX, 60, columnWidth, 25, "y-max" );
	setComponentFontSize(yMaxLabel, fontSize);
	mountComponent( yMaxLabel, window );

	yMaxField = newTextField( lowX+columnWidth, 60, columnWidth, 25, DEFAULT_Y_MAX );
	setComponentFontSize(yMaxField, fontSize);
	mountComponent( yMaxField, window );

	int yMinLabel = newTextLabel( lowX, 90, columnWidth, 25, "y-min" );
	setComponentFontSize(yMinLabel, fontSize);
	mountComponent( yMinLabel, window );

	yMinField = newTextField( lowX+columnWidth, 90, columnWidth, 25, DEFAULT_Y_MIN );
	setComponentFontSize(yMinField, fontSize);
	mountComponent( yMinField, window );

	int yNLabel = newTextLabel( lowX, 120, columnWidth, 25, "y-N" );
	setComponentFontSize(yNLabel, fontSize);
	mountComponent( yNLabel, window );

	yNField = newTextField( lowX+columnWidth, 120, columnWidth, 25, DEFAULT_Y_N );
	setComponentFontSize(yNField, fontSize);
	mountComponent( yNField, window );


	plotButton = newButton( 10, 160, buttonWidth, 50, "PLOT" );
	setComponentFontSize(plotButton, fontSize);
	mountComponent( plotButton, window );


	clearButton = newButton( 10, 220, buttonWidth, 50, "CLEAR" );
	setComponentFontSize(clearButton, fontSize);
	mountComponent( clearButton, window );

	exportButton = newButton( 10, 280, buttonWidth, 50, "EXPORT" );
	setComponentFontSize(exportButton, fontSize);
	mountComponent( exportButton, window );

	exitButton = newButton( 10, 340, buttonWidth, 50, "EXIT" );
	setComponentFontSize(exitButton, fontSize);
	mountComponent( exitButton, window );
}


/**
 * Exports data of the current graph to a file.
 */
void exportFile(){

	// Choose the file path to export.
	string exportFilePath[] = choose();
	if (length(exportFilePath) == 0) {
		return; // Case of nothing has chosen.
	}

	// If the file path has no extension, append it.
	string name = getFileName( exportFilePath[0] );
	if( indexOf(name,".") < 0 ){
		exportFilePath += ".dat3d";
	}

	// Export to a file.
	exportGraph3DData(graph, exportFilePath[0], "COLUMN_TSV");

	// Show message of completion.
	pop( "SAVED: " + exportFilePath[0] );
}


/**
 * Invoked when buttons are clicked (event handler).
 * 
 * @param id   The ID of the clicked button.
 */
void onButtonClick( int id ){

	// Case of PLOT button is clicked.
	if( id == plotButton ){
		
		// Get the inputted expression of z(x,y).
		string zExpression = getComponentText( expressionField );

		// Check syntax of inputted contents of x-max, x-min, x-N, etc.
		if( !evaluable( getComponentText( xMaxField ), 0.0 ) ){
			alert("The form of the expression of x-max is wrong.");
			return;
		}
		if( !evaluable( getComponentText( xMinField ), 0.0 ) ){
			alert("The form of the expression of x-min is wrong.");
			return;
		}
		if( !evaluable( getComponentText( xNField ), 0.0 ) ){
			alert("The form of the expression of x-N is wrong.");
			return;
		}
		if( !evaluable( getComponentText( yMaxField ), 0.0 ) ){
			alert("The form of the expression of y-max is wrong.");
			return;
		}
		if( !evaluable( getComponentText( yMinField ), 0.0 ) ){
			alert("The form of the expression of y-min is wrong.");
			return;
		}
		if( !evaluable( getComponentText( yNField ), 0.0 ) ){
			alert("The form of the expression of y-N is wrong.");
			return;
		}

		// Evaluate values of x-max, x-min, x-N.
		double xMax = feval( getComponentText( xMaxField ), 0.0 );
		double xMin = feval( getComponentText( xMinField ), 0.0 );
		int xN = feval( getComponentText( xNField ), 0.0 );

		// Evaluate values of y-max, y-min, y-N.
		double yMax = feval( getComponentText( yMaxField ), 0.0 );
		double yMin = feval( getComponentText( yMinField ), 0.0 );
		int yN = feval( getComponentText( yNField ), 0.0 );

		// Plot the inputted expression of z(x,y) to the graph.
		// ( "plotGraph" function is declared at near the top of this program. )
		plotGraph( zExpression, xMin, xMax, xN, yMin, yMax, yN );
		return;
	}

	// Case of CLEAR button is clicked.
	if( id == clearButton ){
		clearGraph3D(graph);
		return;
	}

	// Case of EXPORT button is clicked.
	if( id == exportButton ){
		exportFile();
		return;
	}

	// Case of EXIT button is clicked.
	if( id == exitButton ){
		exit();
		return;
	}
}


/**
 * Invoked when windows are closed (event handler).
 * 
 * @param id   The ID of the closed window.
 */
void onWindowClose( int id ){
	if( id == window ){
		exit();
		return;
	}
}


/**
 * Invoked when graphs are closed (event handler).
 * 
 * @param id   The ID of the closed graph.
 */
void onGraph3DClose( int id ){
	if( id == graph ){
		exit();
		return;
	}
}