import mpi.*;

public class Model {


	

	public static void main (String args[]) {

 		int node = 0;
		int numberOfNodes = 0;

		try {

			MPI.Init(args);
			node = MPI.COMM_WORLD.Rank();
			numberOfNodes = MPI.COMM_WORLD.Size();


		} catch (MPIException mpiE) {
 
			mpiE.printStackTrace();
 
		}


		int width = 10;
		int height = 10;
		int densityLimit = 100;
		int numberOfAgents = 1000;
		int nodeNumberOfAgents = 0; 
		int iterations = 100;
		Agent [] agents = null;

		Landscape landscape = new Landscape();
		landscape.setWidth(width);
		landscape.setHeight(height);


		// Setup

		if (node != 0) {

   			nodeNumberOfAgents = numberOfAgents/(numberOfNodes - 1);
 
   			if (node == (numberOfNodes - 1)) {
				nodeNumberOfAgents = nodeNumberOfAgents + (numberOfAgents % (numberOfNodes - 1));
   			}

			agents = new Agent[nodeNumberOfAgents];
 
			for (int i = 0; i < nodeNumberOfAgents; i++) {

				agents[i] = new Agent();
				agents[i].setDensityLimit(densityLimit);

				agents[i].setLandscape(landscape);

				int x = (new Double(Math.random()*(double)width)).intValue();
				int y = (new Double(Math.random()*(double)height)).intValue();

				agents[i].setX(x); 
				agents[i].setY(y); 

			} 

			landscape.setAgents(agents);

		}



		// Run

		int[] densities = null;
 
		for (int time = 0; time < iterations; time++) {





			// Send out the local densities to node zero


			if (node != 0) {
  
				landscape.calcDensities();
 
				densities = landscape.getDensities();

				//for (int a = 0; a < densities.length; a++) System.out.print (densities[a] + " a = " + a);



				try {
 
         				MPI.COMM_WORLD.Send(densities, 0, width * height, MPI.INT, 0, 50);
 
				} catch (MPIException mpiE) {
 
					mpiE.printStackTrace();
 
      				}


   			} else { // if node is node zero





			// Get the local densities in to node zero

 
				densities = new int [width*height];

      			for (int i = 1; i < numberOfNodes; i++) {
 
         				// Get the local density from each node i.
 
         				int[] localDensities = new int [width*height];
 
         				try {
 
           					MPI.COMM_WORLD.Recv(localDensities, 0, width * height, MPI.INT, i, 50);
 
         				} catch (MPIException mpiE) {
 
            				mpiE.printStackTrace();
 
					}
 
         				// Add node i's density surface to the global surface.
 
         				for (int x = 0; x < width; x++) {
 
            				for (int y = 0; y < height; y++) {
 
               					densities[(y*width) + x] = densities[(y*width) + x] + localDensities[(y*width) + x];
 
            				}
 
         				}
 
     				 } // End of looping through nodes.
 
   			} // End of if not node zero loop from above.
 
		


			// Send out the global densities to the nodes


			if (node == 0) {
 
      			for (int i = 1; i < numberOfNodes; i++) {
 
         				try {
 
            				MPI.COMM_WORLD.Send(densities, 0, width * height, MPI.INT, i, 100);
 
         				} catch (MPIException mpiE) {
 
            				mpiE.printStackTrace();
 
         				}
 
      			}
 
   			} else {
 




			// Receive the global densities from node zero.


      			int [] globalDensities = new int [width*height];
 
      			try {
 
         				MPI.COMM_WORLD.Recv(globalDensities, 0, width * height, MPI.INT, 0, 100);
 
      			} catch (MPIException mpiE) {
 
         				mpiE.printStackTrace();
 
      			}
 
      			landscape.setDensities(globalDensities);
 



				// Move the agents if the density is too high.

      			for (int i = 0; i < nodeNumberOfAgents; i++) { 
 
         				agents[i].step();
 
      			}
 


   			} // End of if node is zero
 
		} // End of time iterations loop from above.






		// Report

		landscape.setDensities(densities); 

		if (node == 0) {
			for (int x = 0 ; x < width; x++) {
				for (int y = 0; y < height; y++) {
					System.out.print(landscape.getDensity(x,y) + " ");
				} 
				System.out.println("");
			}
		}


		try {

			MPI.Finalize();

		} catch (MPIException mpiE) {
 
			mpiE.printStackTrace();
 
		}



	}




}