import java.util.concurrent.Semaphore;

import java.io.PrintWriter;
import java.io.FileWriter;

public enum Error
{
   WARNING("[W]"),
   ERROR("[E]"),
   FATAL("[F]"),
   PROGRAM("[P]"); /* Errors that should not if the code's logic was correct. */

   private static final Semaphore MUTEX;
   private static PrintWriter OUTPUT;
   private final String emblem;
   private int count;

   static
   {
      MUTEX = new Semaphore(1);
   }

   private Error (final String emblem)
   {
      this.emblem = emblem;
      this.count = 0;
   }

   public static int init_handler ()
   {
      try
      {
         OUTPUT =
            new PrintWriter
            (
               new FileWriter(Parameters.get_log_filename())
            );
      }
      catch (final Exception e)
      {
         System.err.println("[F] Could not init the Error Handler:");
         e.printStackTrace();

         return -1;
      }

      return 0;
   }

   public static void finalize_handler ()
   {
      OUTPUT.flush();
      OUTPUT.close();

      summary();
   }

   public void from_thread
   (
      final String thread_id,
      final String error
   )
   {
      try
      {
         MUTEX.acquire();

         OUTPUT.print(emblem);
         OUTPUT.print("[Thread: ");
         OUTPUT.print(thread_id);
         OUTPUT.print("] ");
         OUTPUT.println(error);

         ++count;

         MUTEX.release();
      }
      catch (final InterruptedException ie)
      {
         System.err.println
         (
            "[W] An thread was interrupted while trying to report an error."
         );
      }
   }

   public void from_thread
   (
      final String thread_id,
      final String error,
      final String report
   )
   {
      try
      {
         MUTEX.acquire();

         OUTPUT.print(emblem);
         OUTPUT.print("[Thread: ");
         OUTPUT.print(thread_id);
         OUTPUT.print("] ");
         OUTPUT.println(error);
         OUTPUT.println(report);

         ++count;

         MUTEX.release();
      }
      catch (final InterruptedException ie)
      {
         System.err.println
         (
            "[W] An thread was interrupted while trying to report an error."
         );
      }
   }

   public void from_file
   (
      final String filename,
      final String error
   )
   {
      try
      {
         MUTEX.acquire();

         OUTPUT.print(emblem);
         OUTPUT.print("[File: ");
         OUTPUT.print(filename);
         OUTPUT.print("] ");
         OUTPUT.println(error);

         ++count;

         MUTEX.release();
      }
      catch (final InterruptedException ie)
      {
         System.err.println
         (
            "[W] An thread was interrupted while trying to report an error."
         );
      }
   }

   public void from_file
   (
      final String filename,
      final String error,
      final String report
   )
   {
      try
      {
         MUTEX.acquire();

         OUTPUT.print(emblem);
         OUTPUT.print("[File: ");
         OUTPUT.print(filename);
         OUTPUT.print("] ");
         OUTPUT.println(error);
         OUTPUT.println(report);

         ++count;

         MUTEX.release();
      }
      catch (final InterruptedException ie)
      {
         System.err.println
         (
            "[W] An thread was interrupted while trying to report an error."
         );
      }
   }

   private static void summary ()
   {
      final StringBuilder sb;

      sb = new StringBuilder();

      sb.append("Log report:\n");

      for (final Error e: Error.values())
      {
         sb.append(e.emblem);
         sb.append(" ");
         sb.append(e.count);
         sb.append("\n");
      }

      System.out.println(sb.toString());
   }
}