// CSE 373 Homework 2: Star Chart
// YOU DO NOT NEED TO MODIFY THIS INSTRUCTOR-PROVIDED FILE.
// Your code should work properly with an unmodified version of this file.

import java.awt.*;
import java.io.*;
import java.util.*;
import java.util.List;

/**
 * This program runs the star chart simulator.
 * It reads the input data from the star and constellation files
 * that will be passed in to your StarChart object.
 */
public class Main {
	// constants for important file names and settings;
	// these can be changed to alter the program's default behavior
	private static final String STARS_FILENAME = "stars.txt";
	private static final int DEFAULT_SIZE = 500;
	private static final boolean ALWAYS_ON_TOP = true;
	
	/** Runs the program. */
	public static void main(String[] args) throws FileNotFoundException {
		System.out.println("CSE 373 Star Chart Display");
		System.out.println("==========================");
		System.out.println("This program shows charts of stars in the sky");
		System.out.println("and constellations based on an input data file.");
		System.out.println();
		
		Scanner console = new Scanner(System.in);
		DrawingPanel panel = createWindow(console);
		StarChart chart = new StarChart(panel.getWidth(), panel.getHeight());
		readStarsFile(STARS_FILENAME, chart);
		
		// draw the stars on a DrawingPanel on screen
		chart.draw(panel.getGraphics(), false);
		
		// text menu for user commands
		menu(console, panel, chart);
		
		System.out.println("Exiting.");
		panel.setVisible(false);
		System.exit(0);
	}
	
	/** Presents a text menu of choices to the user and runs the proper command. */
	public static void menu(Scanner console, DrawingPanel panel, StarChart chart)
			throws FileNotFoundException {
		boolean starNamesEnabled = false;
		Graphics g = panel.getGraphics();
		String command = "";
		while (!command.equals("Q")) {
			System.out.print("C)onstellation, D)istance, N)ames, S)upernova, Q)uit? ");
			command = console.nextLine().trim().toUpperCase();
			if (command.equals("C")) {
				System.out.print("Constellation filename to add? ");
				String fileName = console.nextLine().trim();
				readConstellationFile(fileName, chart);
			} else if (command.equals("N")) {
				starNamesEnabled = !starNamesEnabled;
				System.out.println("Star names are now " + 
						(starNamesEnabled ? "enabled." : "disabled."));
			} else if (command.equals("D")) {
				System.out.print("Star name or x/y coordinates for star #1? ");
				Star star1 = promptForStar(console, chart);
				System.out.print("Star name or x/y coordinates for star #2? ");
				Star star2 = promptForStar(console, chart);
				if (star1 != null && star2 != null) {
					double distance = star1.distance(star2);
					System.out.printf("Distance from %s to %s is roughly %.4f\n",
							star1, star2, distance);
				}
			} else if (command.equals("S")) {
				System.out.print("Star name or x/y coordinates to go supernova? ");
				Star novaStar = promptForStar(console, chart);
				if (novaStar != null) {
					int destroyed = chart.supernova(novaStar);
					System.out.println(destroyed + " star(s) were destroyed!");
				}
			}
			
			panel.clear();
			chart.draw(g, starNamesEnabled);
		}
	}
	
	/** Creates and returns a new drawing panel based on the user's preferred size. */ 
	public static DrawingPanel createWindow(Scanner console) {
		System.out.print("Window width and height (Enter for default " + 
				DEFAULT_SIZE + " x " + DEFAULT_SIZE + ")? ");
		String line = console.nextLine();
		int width = DEFAULT_SIZE;
		int height = DEFAULT_SIZE;
		Scanner tokens = new Scanner(line);
		if (tokens.hasNextInt()) {
			width = tokens.nextInt();
		}
		// allow skipping a comma or x between w and h
		while (tokens.hasNext() && !tokens.hasNextInt()) {
			tokens.next();
		}
		if (tokens.hasNextInt()) {
			height = tokens.nextInt();
		}
		DrawingPanel panel = new DrawingPanel(width, height);
		panel.setBackground(Color.BLACK);
		panel.setAlwaysOnTop(ALWAYS_ON_TOP);
		return panel;
	}
	
	/** Prompts the user to type the name or coordinates of a star, and returns it. */
	public static Star promptForStar(Scanner console, StarChart chart) {
		String starName = console.nextLine().trim();
		Star star = null;
		Scanner tokens = new Scanner(starName);
		if (tokens.hasNextDouble()) {
			double x = tokens.nextDouble();
			if (tokens.hasNextDouble()) {
				double y = tokens.nextDouble();
				star = chart.getStar(x, y);
			}
		} else {
			star = chart.getStar(starName);
		}
		
		if (star == null) {
			System.out.println("Star \"" + starName + "\" not found.");
		}
		return star;
	}
	
	/** Reads star input data from the given file and adds it to the star chart. */
	public static void readStarsFile(String fileName, StarChart chart)
			throws FileNotFoundException {
		System.out.println("Reading stars input data ...");
		File file = new File(fileName);
		if (!file.exists()) {
			System.out.println("File \"" + fileName + "\" not found.");
			return;
		}
		
		// Each line contains the x/y/z, an ID, a magnitude,
		// another ID, and possibly a star name at the end.  Examples:
		// 0.783 0.312 -0.537 887 6.57 423
		// 0.010 0.007 0.999 889 1.97 424 Polaris
		Scanner input = new Scanner(new File(fileName));
		while (input.hasNextLine()) {
			Scanner tokens = new Scanner(input.nextLine());
			double x = tokens.nextDouble();
			double y = tokens.nextDouble();
			double z = tokens.nextDouble();
			tokens.nextInt();  // Draper id; ignored
			double magnitude = tokens.nextDouble();
			tokens.nextInt();  // Harvard revised id; ignored
			String name = tokens.hasNext() ? tokens.nextLine().trim() : null;
			Star star = new Star(x, y, z, magnitude);
			chart.addStar(star, name);
		}
	}
	
	/** Reads constellation data from the given file and adds it to the star chart. */
	public static void readConstellationFile(String fileName, StarChart chart)
			throws FileNotFoundException {
		if (!fileName.endsWith(".txt") && !fileName.contains(".")) {
			fileName += ".txt";
		}
		File file = new File(fileName);
		if (!file.exists()) {
			System.out.println("File \"" + fileName + "\" not found.");
			return;
		}
		
		// Each line of the input is two stars, such as "Sadr,Cyg Epsilon"
		Scanner input = new Scanner(new File(fileName));
		String constellationName = input.nextLine();
		List<String> starNameList = new ArrayList<String>();
		while (input.hasNextLine()) {
			String[] tokens = input.nextLine().split(",");
			if (tokens.length >= 2) {
				starNameList.add(tokens[0]);
				starNameList.add(tokens[1]);
			}
		}
		String[] starNames = starNameList.toArray(new String[0]);
		chart.addConstellation(starNames, constellationName);
	}
}