/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            cachemanager.cc
 *
 *  Fri Apr 10 10:39:24 CEST 2015
 *  Copyright 2015 Jonas Suhr Christensen 
 *  jsc@umbraculum.org
 ****************************************************************************/

/*
 *  This file is part of DrumGizmo.
 *
 *  DrumGizmo is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  DrumGizmo is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with DrumGizmo; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */
#include "cachemanager.h"

#include <stdio.h>

CacheManager::CacheManager()
{
}

CacheManager::~CacheManager()
{
  wait_stop();
}

void CacheManager::init(int poolsize)
{
  id2cache.resize(poolsize);
  for(int i = 0; i < poolsize; i++) {
    availableids.push_back(i);
  }

  running = true;
  run();
}

// Invariant: initial_samples_needed < preloaded audio data 
sample_t *CacheManager::open(AudioFile *file, int initial_samples_needed, int channel, cacheid_t &id) 
{
  // What if no free ids is available?
  m_ids.lock(); 
  id = availableids.front();
  availableids.pop_front();
  m_ids.unlock();

  cache_t c;
  c.file = file;
  c.channel = channel;
  c.pos = initial_samples_needed;
  // Allocate buffers
  // Increase audio ref count

  id2cache[id] = c;
 
  event_t e;
  e.id = id;
  pushEvent(e);

  return file->data;
}

void CacheManager::close(cacheid_t id)
{
  m_ids.lock();
  availableids.push_back(id);
  m_ids.unlock();

  // Clean cache_t mapped to event
  // Clean event list for other events mapped to this id?
  //    Maybe we need an event for this, that we can push in front of eventqueue (con: we dont read from disk when doing this stuff).
  // Decrement audiofile ref count
}

sample_t *CacheManager::next(cacheid_t id, size_t &size) 
{
  sample_t *s = NULL;
  return s;   
}

void CacheManager::loadNext(cacheid_t id) 
{
  printf("Loading next...\n");

  // If more is left of file 
  if(false) {
    event_t e; 
    e.id = id;
    pushEvent(e);
  }
}

void CacheManager::thread_main()
{
  while(running) {
    sem.wait();
    
    m_events.lock();
    if(eventqueue.empty()) {
      event_t e = eventqueue.front();
      eventqueue.pop_front();
      m_events.unlock();
    
      loadNext(e.id);      
    }
    else {
      m_events.unlock();
    } 
  }
}

void CacheManager::pushEvent(event_t e)
{
  // Check that if event should be merged (Maybe by event queue (ie. push in front).
  m_events.lock();
  eventqueue.push_back(e);
  m_events.unlock();
}