/**
 * PANDA 3D SOFTWARE
 * Copyright (c) Carnegie Mellon University.  All rights reserved.
 *
 * All use of this software is subject to the terms of the revised BSD
 * license.  You should have received a copy of this license along
 * with this source code in a file named "LICENSE."
 *
 * @file texturePool.I
 * @author drose
 * @date 2000-04-26
 * @author fperazzi, PandaSE
 * @date 2010-04-29
 */

/**
 * Returns true if the texture has ever been loaded, false otherwise.
 */
INLINE bool TexturePool::
has_texture(const Filename &filename) {
  return get_global_ptr()->ns_has_texture(filename);
}

/**
 * Loads the given filename up into a texture, if it has not already been
 * loaded, and returns true to indicate success, or false to indicate failure.
 * If this returns true, it is guaranteed that a subsequent call to
 * load_texture() with the same texture name will return a valid Texture
 * pointer.
 */
INLINE bool TexturePool::
verify_texture(const Filename &filename) {
  return load_texture(filename) != nullptr;
}

/**
 * Loads the given filename up into a texture, if it has not already been
 * loaded, and returns the new texture.  If a texture with the same filename
 * was previously loaded, returns that one instead.  If the texture file
 * cannot be found, returns NULL.
 *
 * If read_mipmaps is true, the filename should contain a hash mark ('#'),
 * which will be filled in with the mipmap level number; and the texture will
 * be defined with a series of images, one for each mipmap level.
 */
INLINE Texture *TexturePool::
load_texture(const Filename &filename, int primary_file_num_channels,
             bool read_mipmaps, const LoaderOptions &options) {
  return get_global_ptr()->ns_load_texture(filename, primary_file_num_channels,
                                           read_mipmaps, options);
}

/**
 * Loads the given filename up into a texture, if it has not already been
 * loaded, and returns the new texture.  If a texture with the same filename
 * was previously loaded, returns that one instead.  If the texture file
 * cannot be found, returns NULL.
 *
 * If read_mipmaps is true, both filenames should contain a hash mark ('#'),
 * which will be filled in with the mipmap level number; and the texture will
 * be defined with a series of images, two for each mipmap level.
 */
INLINE Texture *TexturePool::
load_texture(const Filename &filename, const Filename &alpha_filename,
             int primary_file_num_channels, int alpha_file_channel,
             bool read_mipmaps, const LoaderOptions &options) {
  return get_global_ptr()->ns_load_texture(filename, alpha_filename,
                                           primary_file_num_channels,
                                           alpha_file_channel,
                                           read_mipmaps, options);
}

/**
 * Loads a 3-D texture that is specified with a series of n pages, all
 * numbered in sequence, and beginning with index 0.  The filename should
 * include a sequence of one or more hash characters ("#") which will be
 * filled in with the index number of each level.
 *
 * If read_mipmaps is true, the filename should contain an additional hash
 * mark.  The first hash mark will be filled in with the mipmap level number,
 * and the second with the index number of each 3-d level.
 */
INLINE Texture *TexturePool::
load_3d_texture(const Filename &filename_pattern, bool read_mipmaps,
                const LoaderOptions &options) {
  return get_global_ptr()->ns_load_3d_texture(filename_pattern, read_mipmaps,
                                              options);
}

/**
 * Loads a 2-D texture array that is specified with a series of n pages, all
 * numbered in sequence, and beginning with index 0.  The filename should
 * include a sequence of one or more hash characters ("#") which will be
 * filled in with the index number of each level.
 *
 * If read_mipmaps is true, the filename should contain an additional hash
 * mark.  The first hash mark will be filled in with the mipmap level number,
 * and the second with the index number of each 2-d level.
 */
INLINE Texture *TexturePool::
load_2d_texture_array(const Filename &filename_pattern, bool read_mipmaps,
                const LoaderOptions &options) {
  return get_global_ptr()->ns_load_2d_texture_array(filename_pattern, read_mipmaps,
                                                    options);
}

/**
 * Loads a cube map texture that is specified with a series of 6 pages,
 * numbered 0 through 5.  The filename should include a sequence of one or
 * more hash characters ("#") which will be filled in with the index number of
 * each pagee.
 *
 * If read_mipmaps is true, the filename should contain an additional hash
 * mark.  The first hash mark will be filled in with the mipmap level number,
 * and the second with the face number, 0 through 5.
 */
INLINE Texture *TexturePool::
load_cube_map(const Filename &filename_pattern, bool read_mipmaps,
              const LoaderOptions &options) {
  return get_global_ptr()->ns_load_cube_map(filename_pattern, read_mipmaps,
                                            options);
}

/**
 * Returns a standard Texture object that has been created with
 * Texture::generate_normalization_cube_map().  This Texture may be shared by
 * any application code requiring a normalization cube map.  It will be at
 * least as large as the specified size, though it may be larger.
 */
INLINE Texture *TexturePool::
get_normalization_cube_map(int size) {
  return get_global_ptr()->ns_get_normalization_cube_map(size);
}

/**
 * Returns a standard Texture object that has been created with
 * Texture::generate_alpha_scale_map().
 *
 * This Texture object is used internally by Panda to apply an alpha scale to
 * an object (instead of munging its vertices) when
 * gsg->get_alpha_scale_via_texture() returns true.
 */
INLINE Texture *TexturePool::
get_alpha_scale_map() {
  return get_global_ptr()->ns_get_alpha_scale_map();
}

/**
 * Adds the indicated already-loaded texture to the pool.  The texture must
 * have a filename set for its name.  The texture will always replace any
 * previously-loaded texture in the pool that had the same filename.
 */
INLINE void TexturePool::
add_texture(Texture *texture) {
  get_global_ptr()->ns_add_texture(texture);
}

/**
 * Removes the indicated texture from the pool, indicating it will never be
 * loaded again; the texture may then be freed.  If this function is never
 * called, a reference count will be maintained on every texture every loaded,
 * and textures will never be freed.
 *
 * The texture's name should not have been changed during its lifetime, or
 * this function may fail to locate it in the pool.
 */
INLINE void TexturePool::
release_texture(Texture *texture) {
  get_global_ptr()->ns_release_texture(texture);
}

/**
 * Releases all textures in the pool and restores the pool to the empty state.
 */
INLINE void TexturePool::
release_all_textures() {
  get_global_ptr()->ns_release_all_textures();
}

/**
 * Should be called when the model-path changes, to blow away the cache of
 * texture pathnames found along the model-path.
 */
INLINE void TexturePool::
rehash() {
  get_global_ptr()->_relpath_lookup.clear();
}

/**
 * Releases only those textures in the pool that have a reference count of
 * exactly 1; i.e.  only those textures that are not being used outside of the
 * pool.  Returns the number of textures released.
 */
INLINE int TexturePool::
garbage_collect() {
  return get_global_ptr()->ns_garbage_collect();
}

/**
 * Lists the contents of the texture pool to the indicated output stream.
 */
INLINE void TexturePool::
list_contents(std::ostream &out) {
  get_global_ptr()->ns_list_contents(out);
}

/**
 * Lists the contents of the texture pool to cout
 */
INLINE void TexturePool::
list_contents() {
  get_global_ptr()->ns_list_contents(std::cout);
}

/**
 * Returns the first texture found in the pool that matches the indicated name
 * (which may contain wildcards).  Returns the texture if it is found, or NULL
 * if it is not.
 */
INLINE Texture *TexturePool::
find_texture(const std::string &name) {
  return get_global_ptr()->ns_find_texture(name);
}

/**
 * Returns the set of all textures found in the pool that match the indicated
 * name (which may contain wildcards).
 */
INLINE TextureCollection TexturePool::
find_all_textures(const std::string &name) {
  return get_global_ptr()->ns_find_all_textures(name);
}

/**
 * Sets a bogus filename that will be loaded in lieu of any textures requested
 * from this point on.
 */
INLINE void TexturePool::
set_fake_texture_image(const Filename &filename) {
  get_global_ptr()->_fake_texture_image = filename;
}

/**
 * Restores normal behavior of loading the textures actually requested.
 */
INLINE void TexturePool::
clear_fake_texture_image() {
  set_fake_texture_image(std::string());
}

/**
 * Returns true if fake_texture_image mode has been enabled, false if we are
 * in the normal mode.
 */
INLINE bool TexturePool::
has_fake_texture_image() {
  return !get_fake_texture_image().empty();
}

/**
 * Returns the filename that was specified with a previous call to
 * set_fake_texture_image().
 */
INLINE const Filename &TexturePool::
get_fake_texture_image() {
  return get_global_ptr()->_fake_texture_image;
}

/**
 * Creates a new Texture object of the appropriate type for the indicated
 * filename extension, according to the types that have been registered via
 * register_texture_type().
 */
PT(Texture) TexturePool::
make_texture(const std::string &extension) {
  return get_global_ptr()->ns_make_texture(extension);
}

/**
 * Defines relative ordering between LookupKey instances.
 */
INLINE bool TexturePool::LookupKey::
operator < (const LookupKey &other) const {
  if (_fullpath != other._fullpath) {
    return _fullpath < other._fullpath;
  }
  if (_alpha_fullpath != other._alpha_fullpath) {
    return _alpha_fullpath < other._alpha_fullpath;
  }
  if (_primary_file_num_channels != other._primary_file_num_channels) {
    return _primary_file_num_channels < other._primary_file_num_channels;
  }
  if (_alpha_file_channel != other._alpha_file_channel) {
    return _alpha_file_channel < other._alpha_file_channel;
  }
  return _texture_type < other._texture_type;
}