package bjc.rgens.text.markov;

import java.io.*;

/**
 * Generate text from a markov model of an input text
 *
 * @author ben
 *
 */
public class TextGenerator {
	/**
	 * Main method.
	 *
	 * @param args
	 * 	When used with three arguments, the first represents the k-order
	 * 	of the Markov objects. The second represents the number of
	 * 	characters to print out. The third represents the file to be
	 * 	read. 
	 *
	 * 	When used with two arguments, the first represents the k-order
	 * 	of the Markov objects, and the second represents the file to be
	 * 	read. The generated text will be the same number of characters
	 * 	as the original file.
	 */
	public static void main(String[] args) {
		int k = 0;
		int M = 0;

		String file = "";
		StringBuilder text = new StringBuilder();

		if (args.length == 3) {
			k = Integer.parseInt(args[0]);
			M = Integer.parseInt(args[1]);

			file = args[2];
		} else if (args.length == 2) {
			k = Integer.parseInt(args[0]);

			file = args[1];
		} else {
			System.out.println("\n" + "Usage: java TextGenerator k M file");
			System.out.println("where k is the markov order, M is the number");
			System.out.println("of characters to be printed, and file is the");
			System.out.println("name of the file to print from. M may be left out." + "\n");
			System.exit(1);
		}

		StandaloneMarkov markov = null;

		try (FileReader reader = new FileReader(file)) {
			markov = StandaloneTextGenerator.generateMarkovMap(k, reader);

			String generatedText = markov.generateTextFromMarkov(M);
			String desiredText = generatedText.substring(0, Math.min(M, text.length()));

			System.out.println(desiredText);
		} catch (FileNotFoundException e) {
			System.out.println("File not found.");

			e.printStackTrace();

			System.exit(1);
		} catch (IOException ioex) {
			System.out.println("IOException");

			ioex.printStackTrace();

			System.exit(1);
		}
	}
}