package cz.cuni.amis.utils;
   
   import java.util.HashSet;
   import java.util.LinkedList;
   import java.util.Queue;
   import java.util.Set;
   
   /**
    * Used to produce text strings during tests, those strings are then consumed by the
   * test case.
   * <p><p>
   * Used to control that everything is OK in tested objects / classes.
   * 
   * @author Jimmy
   */
  public class TestOutput {
  	
  	/**
  	 * Flag whether to print the output to console.
  	 */
  	private static boolean log = false;
  	
  	/**
  	 * Queue with strings somebody produce.
  	 */
  	private Queue<String> output = new LinkedList<String>();
  
  	private String name;
  	
  	public TestOutput(String name) {
  		this.name = name;
  	}
  	
  	/**
  	 * Adds next String to the queue.
  	 * @param output
  	 */
  	public void push(String output) {		
  		this.output.add(output);
  	}
  	
  	/**
  	 * Consume many strings from the output - if not equals, returns false as failure.
  	 * @param outputs
  	 * @return
  	 */
  	public boolean consumeMany(String... outputs) {
  		for (String output : outputs) {
  			if (!consume(output)) return false;
  		}
  		return true;
  	}
  	
  	/**
  	 * Consume string symbol from the queue - false is failure (string didn't match).
  	 * @param output
  	 * @return
  	 */
  	public boolean consume(String output) {
  		if (log) System.out.println("CONSUME "+name+" expected : " + String.valueOf(output));
  		if (this.output.size() == 0) {
  			if (log) System.out.println("CONSUME "+name+": no output, can't consume: " + output);
  			return false;
  		}
  		if (output == null) {	
  			String str = this.output.poll();
  			boolean result = str == null;
  			if (log) 
  				if (result) {
  					System.out.println("CONSUME "+name+" got      : "+String.valueOf(str));
  				} else {
  					System.out.println("CONSUME "+name+" got      : "+String.valueOf(str));
  				}
  			return result;
  		}
  		String str = this.output.poll();
  		boolean result = output.equals(str);
  		if (log) 
  			if (result) {
  				System.out.println("CONSUME "+name+" got      : "+String.valueOf(str));
  			} else {
  				System.out.println("CONSUME "+name+" got      : "+String.valueOf(str));
  			}
  		return result;		
  	}
  	
  	/**
  	 * Try to consume many strings, false - one of them didn't match, failure.
  	 * @param output
  	 * @return
  	 */
  	public boolean consume(String[] output) {
  		for (String str : output) {
  			if (!consume(str)) return false;		
  		}
  		return true;
  	}
  	
  	/**
 	 * Consume output in any order, returns false if first output.length string in 
 	 * the queue can't be matched to the output strings.
 	 * @param output
 	 * @return
 	 */
 	public boolean consumeAnyOrder(String[] output) {
 		Set<String> outputSet = new HashSet<String>();
 		for (String str : output) {
 			if (log) System.out.println("CONSUME expected : " + String.valueOf(str));
 			outputSet.add(str);
 		}
 		if (this.output.size() < output.length) {
 			if (log) {
 				System.out.println("CONSUME "+name+": not enough output (size = " + this.output.size() + "), needed " + output.length);
 				while (this.output.size() != 0) {
 					System.out.println("CONSUME "+name+" listing left output: " + String.valueOf(this.output.poll()));
 				}
 			}
 			return false;
 		}
 		for (int i = 0; i < output.length; ++i) {
 			String str = this.output.poll();
 			if (outputSet.contains(str)) {
 				if (log) System.out.println("CONSUME "+name+" got      : "+str);
 				outputSet.remove(str);
 			} else {
 				if (log) {
 					System.out.println("CONSUME "+name+" got wrong: " + str);
 					while (this.output.size() != 0) {
 						System.out.println("CONSUME "+name+" listing left output: " + String.valueOf(this.output.poll()));
 					}
 				}
 				return false;
 			}
 		}
 		return true;	
 	}
 	
 	/**
 	 * Whether the queue is clear.
 	 * @return
 	 */
 	public boolean isClear(boolean printIfNot) {
 		if (log) System.out.println("OUTPUT "+name+" cleared?");
 		if (output.size() == 0) {
 			if (log) System.out.println("OUTPUT "+name+" yes");
 			return true;
 		} else {
 			if (log) System.out.println("OUTPUT "+name+" NO");
 			if (printIfNot && log) {
 				printOutput();
 			}
 			return false;
 		}
 	}
 
 	/**
 	 * Clear the queue.
 	 */
 	public void clear() {
 		output.clear();		
 	}
 	
 	public void printOutput() {
 		for (String str : this.output) {
 			System.out.println("OUTPUT " + name + ": " + str);
 		}
 	}
 
 	/**
 	 * Do we print the messages to the console (simple logging),
 	 * @return
 	 */
 	public static boolean isLog() {
 		return log;
 	}
 
 	/**
 	 * Set simple console logging.
 	 * @param log
 	 */
 	public static void setLog(boolean log) {
 		TestOutput.log = log;
 	}
 
 }