/* 
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   This program 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, or (at your option)
   any later version.

   ### File Specific:
   main-programmer: Benjamin Grauer
   co-programmer: ...
*/

#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_LOAD

#include "resource_manager.h"

// different resource Types
#include "objModel.h"
#include "primitive_model.h"
#include "texture.h"

#include "list.h"

// File Handling Includes
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

using namespace std;

/**
   \brief standard constructor
*/
ResourceManager::ResourceManager () 
{
   this->setClassName ("ResourceManager");
   dataDir = NULL;
   imageDirs = new tList<char>();
   resourceList = new tList<Resource>();
}

ResourceManager* ResourceManager::getInstance(void)
{
  if (!ResourceManager::singletonRef)
    ResourceManager::singletonRef = new ResourceManager();
  return ResourceManager::singletonRef;
}

//! Singleton Reference to the ResourceManager
ResourceManager* ResourceManager::singletonRef = NULL;
//! The List of Resources, that has already been loaded.
tList<Resource>* ResourceManager::resourceList = NULL;
//! The Data Directory, where all relevant Data is stored.
char* ResourceManager::dataDir = NULL;
//! A list of directories in which images are stored.
tList<char>* ResourceManager::imageDirs = NULL;

/**
   \brief standard deconstructor
*/
ResourceManager::~ResourceManager (void) 
{

  delete resourceList;
  resourceList = NULL;
  ResourceManager::singletonRef = NULL;
}

/**
   \brief sets the data main directory
   \param dataDir the DataDirectory.
*/
bool ResourceManager::setDataDir(char* dataDir)
{
  if (isDir(dataDir))
    {
      ResourceManager::dataDir = new char[strlen(dataDir)+1];
      strcpy(ResourceManager::dataDir, dataDir);
    }
  else
    {
      PRINTF(1)("%s is not a Directory, and can not be the Data Directory\n", dataDir);
    }
}

bool ResourceManager::addImageDir(char* imageDir)
{
  if (isDir(imageDir))
    {
      char* tmpDir  = new char[strlen(imageDir)+1];
      strcpy(tmpDir, imageDir);
      imageDirs->add(tmpDir);
    }
  else
    {
      PRINTF(1)("%s is not a Directory, and can not be added to the Paths of Images\n", dataDir);
    }
}

/**
   \brief loads resources
   \param fileName The fileName of the resource to load
   \returns a pointer to a desired Resource.
*/
void* ResourceManager::load(const char* fileName)
{
  ResourceType tmpType;
  if (!strncmp(fileName+(strlen(fileName)-4), ".obj", 4))
    tmpType = OBJ;
  else if (!strncmp(fileName+(strlen(fileName)-4), ".wav", 4))
    tmpType = WAV;
  else if (!strncmp(fileName+(strlen(fileName)-4), ".mp3", 4))
    tmpType = MP3;
  else if (!strncmp(fileName+(strlen(fileName)-4), ".ogg", 4))
    tmpType = OGG;
  else if (!strcmp(fileName, "cube") ||
           !strcmp(fileName, "sphere") ||
	   !strcmp(fileName, "plane") ||
           !strcmp(fileName, "cylinder") ||
           !strcmp(fileName, "cone"))
    tmpType = PRIM;
  else 
    tmpType = IMAGE;

  return ResourceManager::load(fileName, tmpType);
}

/**
   \brief loads resources
   \param fileName The fileName of the resource to load
   \param type The Type of Resource to load (\see ResourceType)
   \returns a pointer to a desired Resource.
*/
void* ResourceManager::load(const char* fileName, ResourceType type)
{
  // searching if the resource was loaded before.
  Resource* tmpResource = ResourceManager::locateResourceByName(fileName);
  char* tmpDir;
  if (!tmpResource) // if the resource was not loaded before.
    {
      // Setting up the new Resource
      tmpResource = new Resource;
      tmpResource->count = 1;
      tmpResource->type = type;
      tmpResource->name = new char[strlen(fileName)+1];
      strcpy(tmpResource->name, fileName);

      // creating the full name. (directoryName + FileName)
      char* fullName = new char[strlen(dataDir)+strlen(fileName)+1];
      sprintf(fullName, "%s%s", dataDir, fileName);
      
      // Checking for the type of resource \see ResourceType
      switch(type)
	{
	case OBJ:
	  if(isFile(fullName))
	    tmpResource->pointer = new OBJModel(fullName);
	  else
	    {
	      PRINTF(2)("Sorry, %s does not exist. Loading a cube-Model instead\n", fullName);
	      tmpResource->pointer = ResourceManager::load("cube", PRIM);
	    }
	  break;
	case PRIM:
	  if (!strcmp(tmpResource->name, "cube"))
	    tmpResource->pointer = new PrimitiveModel(CUBE);
	  else if (!strcmp(tmpResource->name, "sphere"))
	    tmpResource->pointer = new PrimitiveModel(SPHERE);
	  else if (!strcmp(tmpResource->name, "plane"))
	    tmpResource->pointer = new PrimitiveModel(PLANE);
	  else if (!strcmp(tmpResource->name, "cylinder"))
	    tmpResource->pointer = new PrimitiveModel(CYLINDER);
	  else if (!strcmp(tmpResource->name, "cone"))
	    tmpResource->pointer = new PrimitiveModel(CONE);
	  break;
	case IMAGE:
	  if(isFile(fullName))
	    {
	      tmpResource->pointer = new Texture(fullName);
	    }
	  else
	    {
	      tmpDir = imageDirs->enumerate();
	      while(tmpDir)
		{
		  char* imgName = new char[strlen(tmpDir)+strlen(fileName)+1];
		  sprintf(imgName, "%s%s", tmpDir, fileName);
		  if(isFile(imgName))
		    tmpResource->pointer = new Texture(imgName);
		  delete []imgName;
		  tmpDir = imageDirs->nextElement();
		}
	    }
	  if(!tmpResource)
	     PRINTF(2)("!!Image %s not Found!!\n", fileName);
	  break;
	default:
	  tmpResource->pointer = NULL;
	  PRINTF(1)("No type found for %s.\n   !!This should not happen unless the Type is not supported yet.!!\n", tmpResource->name);
	  break;
	}
      
      // checking if the File really exists.
      if(!isFile(fullName))
	{
	  PRINTF(2)("Sorry, %s is not a regular file.\n", fullName);
	  tmpResource->pointer = NULL;
	}
      resourceList->add(tmpResource);
      delete []fullName;

    }
  else
    {
      tmpResource->count++;
    }

  return tmpResource->pointer;
}

/**
   \brief unloads a Resource
   \param pointer The pointer to free
   \returns true if successful (pointer found, and deleted), false otherwise
   
*/
bool ResourceManager::unload(void* pointer)
{
  // if pointer is existent. and only one resource of this type exists.
  Resource* tmpResource = ResourceManager::locateResourceByPointer(pointer);
  if (!tmpResource)
    {
      PRINTF(2)("Resource not Found %p\n", pointer);
      return false;
    }
  tmpResource->count--;
  if (tmpResource->count <= 0)
    {
      // deleting the Resource
      switch(tmpResource->type)
	{
	case OBJ:
	case PRIM:
	  delete (Model*)tmpResource->pointer;
	  break;
	case IMAGE:
	  delete (Texture*)tmpResource->pointer;
	  break;
	default:
	  PRINTF(1)("NOT YET IMPLEMENTED FIX FIX\n");
	  return false;
	  break;
	}
      // deleting the List Entry:
      PRINTF(4)("Resource %s Safely removed.\n", tmpResource->name);
      delete []tmpResource->name;
      resourceList->remove(tmpResource);
    }
  else
    PRINTF(4)("Resource not removed, because there are still %d References to it.\n", tmpResource->count);
  return true;
}

/**
   \brief Searches for a Resource by Name
   \param fileName The name to look for
   \returns a Pointer to the Resource if found, NULL otherwise.
*/
Resource* ResourceManager::locateResourceByName(const char* fileName)
{
  Resource* enumRes = resourceList->enumerate();
  while (enumRes)
    {
      if (!strcmp(fileName, enumRes->name))
	return enumRes;
      enumRes = resourceList->nextElement();
    }
  return NULL;
}

/**
   \brief Searches for a Resource by Pointer
   \param pointer the Pointer to search for
   \returns a Pointer to the Resource if found, NULL otherwise.
*/
Resource* ResourceManager::locateResourceByPointer(const void* pointer)
{
  Resource* enumRes = resourceList->enumerate();
  while (enumRes)
    {
      if (pointer == enumRes->pointer);
	return enumRes;
      enumRes = resourceList->nextElement();
    }
  return NULL;
}

/**
   \brief Checks if it is a Directory
   \param directoryName the Directory to check for
   \returns true if it is a directory/symlink false otherwise
*/
bool ResourceManager::isDir(const char* directoryName)
{
  struct stat status;
  stat(directoryName, &status);
  if (status.st_mode & (S_IFDIR | S_IFLNK))
    return true;
  else
    return false;
}

/**
   \brief Checks if the file is either a Regular file or a Symlink
   \param fileName the File to check for
   \returns true if it is a regular file/symlink, false otherwise
*/
bool ResourceManager::isFile(const char* fileName)
{
  struct stat status;
  stat(fileName, &status);
  if (status.st_mode & (S_IFREG | S_IFLNK))
    return true;
  else
    return false;
}