package es.capgemini.audit;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

public class Timer2 {

	private static List<TimerEntry> timeEntries = new ArrayList<TimerEntry>();
	private static HashMap<String, TimerEntry> teMap = new HashMap<String, TimerEntry>();
	private static TimerEntry lastStartedTimer = null;

	private Timer2() {}

	public static void start(String tag) {
		TimerEntry te = new TimerEntry(tag);
		if (lastStartedTimer != null) {
			lastStartedTimer.addChild(te);
		} else {
			timeEntries.add(te);
		}
		lastStartedTimer = te;
		teMap.put(tag, te);
		System.out.println("TIMER START " + te.toString());
	}

	public static void stop(String tag) {
		if (teMap.containsKey(tag)) {
			TimerEntry te = teMap.get(tag);
			if (!te.isStopped()) {
				te.stop();
				lastStartedTimer = te.getRunningParent();
				System.out.println("TIMER STOP " + te.toString());
			} else {
				System.err.println("TIMER ERROR - Timar ya habia finalizado. " + tag);
			}
		} else {
			System.err.println(" TIMER ERROR - no hay timer " + tag);
		}
	}

	public static void printTimes() {
		StringBuilder sb = new StringBuilder("\nTIMER: ======================================");
		timeEntries.forEach((te) -> {
			sb.append("\n" + te.toString());
		});
		System.out.println(sb.toString());
	}

	private static class TimerValue {

		Long start;
		Long end;

		public boolean isEnded() {
			return this.end != null;
		}

		public long getDuration() {
			if (isEnded()) {
				return end - start;
			} else {
				return System.currentTimeMillis() - start;
			}
		}

		@Override
		public String toString() {
			return getDuration() + "ms" + ((!isEnded()) ? " (running)" : "");
		}

	}

	private static class TimerEntry {

		TimerValue value;
		List<TimerEntry> children = new ArrayList<TimerEntry>();
		TimerEntry parent;

		String tag;

		public TimerEntry(String tag) {
			this.value = new TimerValue();
			this.value.start = System.currentTimeMillis();
			this.tag = tag;
		}

		public void setParent(TimerEntry te) {
			this.parent = te;
		}

		public void addChild(TimerEntry te) {
			this.children.add(te);
			te.parent = this;
		}

		public void stop() {
			if (!this.value.isEnded()) {
				this.value.end = System.currentTimeMillis();
			} else {
				System.err.println("TIMER: ERROR [" + tag + "] ya se había terminado antes.");
			}
		}

		public boolean isStopped() {
			return this.value.isEnded();
		}

		public TimerEntry getRunningParent() {
			TimerEntry result = null;
			TimerEntry p = this.parent;
			while (p != null) {
				if (!p.isStopped()) {
					result = p;
					break;
				}
				p = p.parent;
			}
			return result;
		}

		public int getDepth() {
			int result = 0;
			TimerEntry p = this.parent;
			while (p != null) {
				result++;
				p = p.parent;
			}
			return result;
		}

		private static String inBrackets(String text) {
			return "[" + fixedLen(text,10) + "]";
		}

		private static String fixedLen(String text, int len) {
			String result = text;
			while (result.length() < len) result+=" ";
			if (result.length() > len) {
				result = result.substring(0, len - 3) + "...";
			}
			return result;
		}

		@Override
		public String toString() {
			StringBuilder sb = new StringBuilder();
			String offset = "";
			for (int i = 0; i < this.getDepth(); i++) offset += "  ";
			sb.append(offset +  inBrackets(tag));
			if (children.size() > 0) {
				sb.append("\n");
				children.forEach((child) -> {
					sb.append(child.toString());
				});
				sb.append(offset + inBrackets("/" + tag) + " -> " + value.toString() + "\n" );
			} else {
				sb.append("-> " + value.toString() + "\n");
			}
			return sb.toString();
		}
	}

	public static void main(String[] args) {

		Timer2.start("aplicacion");
			sleep(100);

			Timer2.start("paso1");sleep(50);
			Timer2.stop("paso1");

			Timer2.start("paso2");

				Timer2.start("paso 2.1");
					Timer2.start("paso 2.1.1");sleep(50);
					Timer2.stop("paso 2.1.1");
				Timer2.stop("paso 2.1"); sleep(50);

				Timer2.start("paso 2.2");		sleep(50);
				Timer2.stop("paso 2.2");

			Timer2.stop("paso2");sleep(50);

			Timer2.start("paso3");sleep(50);
			Timer2.stop("paso3");

		Timer2.stop("aplicacion");
		Timer2.printTimes();
	}

	private static void sleep(int time) {
		try {
			Thread.currentThread().sleep(time);
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
	}

}