/*
 * Copyright 2009, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

namespace o3d {

%[
 The Buffer object is a low level container for a flat list of
 floating point or integer values. These are currently used to define
 geometry.
%]
[nocpp, include="core/cross/buffer.h"]
class Buffer : NamedObject {
  %[
    Allocates memory for the data to be stored in the buffer based on
    the types of fields set on the buffer.

    \param num_elements Number of elements to allocate..
    \return True if operation was successful.
  %]
  [userglue] bool AllocateElements(unsigned int num_elements);

  %[
    Defines a field on this buffer.

    Note: Creating a field after having allocated the buffer is an expensive
    operation as the data currently in the buffer has to be shuffled around
    to make room for the new field.

    \param field_type type of data in the field. Valid types are "FloatField",
        "UInt32Field", "UByteNField".
    \param num_components number of components in the field.
    \return The created field.
  %]
  [userglue, noreturndocs]
  Field? CreateField(String field_type, unsigned int num_components);

  %[
    Removes a field from this buffer.

    Note: Removing a field after having allocated the buffer is an expensive
    operation as the data currently in the buffer has to be shuffled around
    to remove the old field.

    \param field field to remove.
  %]
  void RemoveField(Field field);

  %[
    Sets the values in the buffer given a RawData object.

    \param raw_data contains data to assign to the Buffer data itself.
    \return True if operation was successful.
  %]
  bool Set(RawData raw_data);

  %[
    Sets the values in the buffer given a RawData object.

    \param raw_data contains data to assign to the Buffer data itself.
    \param offset is a byte offset from the start of raw_data
    \param length is the byte length of the data to set
    \return True if operation was successful.
  %]
  bool Set(RawData raw_data,
           size_t offset,
           size_t length);

  %[
    Number of elements in the buffer.
  %]
  [getter] unsigned int num_elements;

  %[
    The total components in all fields in this buffer.
  %]
  [getter] unsigned int total_components;

  %[
    The fields currently set on the buffer.
  %]
  [userglue_getter, getter] FieldArray fields;

  [verbatim=cpp_glue] %{
    o3d::Field* userglue_method_CreateField(
        o3d::Buffer* buffer,
        const o3d::String& field_type,
        unsigned int num_components) {
      return buffer->CreateFieldByClassName(field_type, num_components);
    }
    o3d::FieldArray userglue_getter_fields(o3d::Buffer* buffer) {
      const o3d::FieldRefArray buffer_fields = buffer->fields();
      o3d::FieldArray fields(buffer_fields.size());
      for (size_t ii = 0; ii < buffer_fields.size(); ++ii) {
        fields[ii] = buffer_fields[ii].Get();
      }
      return fields;
    }
    bool userglue_method_AllocateElements(o3d::Buffer* buffer,
                                          unsigned int num_elements) {
      bool result = buffer->AllocateElements(num_elements);
      if (result) {
        // Clear the buffer so at least from Javascript we can't get garbage.
        o3d::BufferLockHelper locker(buffer);
        void* data = locker.GetData(o3d::Buffer::WRITE_ONLY);
        if (!data) {
          O3D_ERROR(buffer->service_locator())
              << "could not lock buffer";
        } else {
          memset(data, 0, buffer->GetSizeInBytes());
        }
      }
      return result;
    }
  %}
};

%[
  VertexBufferBase is a the base class for both VertexBuffer and SourceBuffer

  \sa o3d.VertexBuffer
  \sa o3d.SourceBuffer
%]
[nocpp, include="core/cross/buffer.h"]
class VertexBufferBase : Buffer {
  %[
    Gets a copy of the values of the data stored in the buffer.
    Modifying this copy has no effect on the buffer.

    \return An array of values.
  %]
  [nocpp, userglue] float[] Get();

  %[
    Gets a copy of a sub range of the values in the data stored in the buffer.
    Modifying this copy has no effect on the buffer.

    \param start_index index of the element value to get.
    \param num_elements the number of elements to get.
    \return An array of values.
  %]
  [nocpp, userglue]
  float[] GetAt(unsigned int start_index, unsigned int num_elements);

  %[
    Sets the values of the data stored in the buffer.
    The number of values passed in must be a multiple of the number of
    components needed for the fields defined on this buffer.

    \param values Values to be stored in the buffer.
    \return True if operation was successful.
  %]
  [nocpp, userglue] bool Set(float[] values);

  %[
    Sets the values of the data stored in the buffer. The buffer must have
    already been created either through buffer.set or buffer.allocateElements

    The number of values passed in must be a multiple of the number of
    components needed for the fields defined on this buffer.

    \param start_index index of first value to set.
    \param values Values to be stored in the buffer starting at index.
  %]
  [nocpp, userglue] void SetAt(unsigned int start_index, float[] values);

  [verbatim=cpp_glue] %{
    std::vector<float> userglue_method_Get(o3d::VertexBufferBase *buffer) {
      std::vector<float> retval;
      o3d::BufferLockHelper helper(buffer);
      float* buffer_data = helper.GetDataAs<float>(
          o3d::Buffer::READ_ONLY);
      if (!buffer_data) {
        O3D_ERROR(buffer->service_locator())
            << "could not lock buffer";
      } else {
        retval.resize(buffer->total_components() * buffer->num_elements());
        unsigned element_offset = 0;
        // for each field, copy the stuff into the array.
        const o3d::FieldRefArray& fields = buffer->fields();
        for (unsigned ff = 0; ff < fields.size(); ++ff) {
          o3d::Field* field = fields[ff];
          field->GetAsFloats(0,
                             &retval[0] + element_offset,
                             field->num_components(),
                             buffer->num_elements());
          element_offset += field->num_components();
        }
      }
      return retval;
    }
    std::vector<float> userglue_method_GetAt(o3d::VertexBufferBase *buffer,
                                             unsigned int start_index,
                                             unsigned int length) {
      std::vector<float> retval;
      if (start_index + length > buffer->num_elements() ||
          start_index + length < start_index) {
        O3D_ERROR(buffer->service_locator())
            << "number of requested values would run past end of buffer";
      } else {
        o3d::BufferLockHelper helper(buffer);
        float* buffer_data = helper.GetDataAs<float>(
            o3d::Buffer::READ_ONLY);
        if (!buffer_data) {
          O3D_ERROR(buffer->service_locator())
              << "could not lock buffer";
        } else {
          retval.resize(length * buffer->total_components());
          unsigned element_offset = 0;
          // for each field, copy the stuff into the array.
          const o3d::FieldRefArray& fields = buffer->fields();
          for (unsigned ff = 0; ff < fields.size(); ++ff) {
            o3d::Field* field = fields[ff];
            field->GetAsFloats(start_index,
                               &retval[0] + element_offset,
                               field->num_components(),
                               length);
            element_offset += field->num_components();
          }
        }
      }
      return retval;
    }
    bool userglue_method_Set(o3d::VertexBufferBase *buffer,
                             const std::vector<float> &values) {
      unsigned int total_components = buffer->total_components();
      size_t size = values.size();
      if (total_components == 0) {
        O3D_ERROR(buffer->service_locator())
            << "no fields are defined on the buffer";
        return false;
      }
      if (size % total_components != 0) {
        O3D_ERROR(buffer->service_locator())
            << "the number of values passed in is not a multiple of the number"
            << " of components in the fields on the buffer.";
        return false;
      }

      unsigned num_elements = size / total_components;

      if (!buffer->AllocateElements(num_elements)) {
        return false;
      }

      o3d::BufferLockHelper helper(buffer);
      void* buffer_data = helper.GetData(o3d::Buffer::WRITE_ONLY);
      if (!buffer_data) {
        O3D_ERROR(buffer->service_locator())
            << "could not lock buffer";
        return false;
      }

      unsigned element_offset = 0;
      // for each field, copy the stuff out of the array.
      const o3d::FieldRefArray& fields = buffer->fields();
      for (unsigned ff = 0; ff < fields.size(); ++ff) {
        o3d::Field* field = fields[ff];
        field->SetFromFloats(&values[element_offset],
                             total_components,
                             0,
                             num_elements);
        element_offset += field->num_components();
      }
      return true;
    }
    void userglue_method_SetAt(o3d::VertexBufferBase *buffer,
                               unsigned int start_index,
                               const std::vector<float> &values) {
      unsigned int total_components = buffer->total_components();
      size_t size = values.size();
      if (total_components == 0) {
        O3D_ERROR(buffer->service_locator())
            << "no fields are defined on the buffer";
        return;
      }
      if (size % total_components != 0) {
        O3D_ERROR(buffer->service_locator())
            << "the number of values passed in is not a multiple of the number"
            << " of components in the fields on the buffer.";
        return;
      }

      unsigned num_elements_to_set = size / total_components;
      unsigned last_element = start_index + num_elements_to_set;
      if (last_element > buffer->num_elements() ||
          last_element < start_index) {
        O3D_ERROR(buffer->service_locator())
           << "Attempt to set elements outside of Buffer";
        return;
      }

      o3d::BufferLockHelper helper(buffer);
      void* buffer_data = helper.GetData(o3d::Buffer::WRITE_ONLY);
      if (!buffer_data) {
        O3D_ERROR(buffer->service_locator())
            << "could not lock buffer";
        return;
      }

      unsigned element_offset = 0;
      // for each field, copy the stuff out of the array.
      const o3d::FieldRefArray& fields = buffer->fields();
      for (unsigned ff = 0; ff < fields.size(); ++ff) {
        o3d::Field* field = fields[ff];
        field->SetFromFloats(&values[element_offset],
                             total_components,
                             start_index,
                             num_elements_to_set);
        element_offset += field->num_components();
      }
    }
  %}
};

%[
  VertexBuffer is a Buffer object used for storing vertex data for geometry.
  (e.g. vertex positions, normals, colors, etc).
  A VertexBuffer can be rendered directly by the GPU.

  \sa o3d.SourceBuffer
%]
[nocpp, include="core/cross/buffer.h"]
class VertexBuffer : VertexBufferBase {
};

%[
  SourceBuffer is a Buffer object used for storing vertex data for
  geometry. (e.g. vertex positions, normals, colors, etc).

  A SourceBuffer is the source for operations like skinning and morph
  targets. It can not be directly rendered by the GPU.

  \sa o3d.VertexBuffer
%]
[nocpp, include="core/cross/buffer.h"]
class SourceBuffer : VertexBufferBase {
};

%[
  IndexBuffer is a buffer object used for storing geometry index data (e.g.
  triangle indices).
%]
[nocpp, include="core/cross/buffer.h"] class IndexBuffer : Buffer {
  %[
    Sets the values of the data stored in the buffer.

    \param values Values to be stored in the buffer.
    \return True if operation was successful.
  %]
  [nocpp, userglue] bool Set(unsigned int[] values);

  %[
    Sets the values of the data stored in the buffer. The buffer must have
    already been created either through buffer.set or buffer.allocateElements.

    \param start_index index of first value to set.
    \param values Values to be stored in the buffer starting at index.
  %]
  [nocpp, userglue] void SetAt(unsigned int start_index, unsigned int[] values);

  [verbatim=cpp_glue] %{
    bool userglue_method_Set(o3d::IndexBuffer *buffer,
                             const std::vector<unsigned int> &values) {
      unsigned int total_components = buffer->total_components();
      size_t size = values.size();
      if (total_components == 0) {
        O3D_ERROR(buffer->service_locator())
            << "no fields are defined on the buffer";
        return false;
      }
      if (size % total_components != 0) {
        O3D_ERROR(buffer->service_locator())
            << "the number of values passed in is not a multiple of the number"
            << " of components in the fields on the buffer.";
        return false;
      }

      unsigned num_elements = size / total_components;

      if (!buffer->AllocateElements(num_elements)) {
        return false;
      }

      o3d::BufferLockHelper helper(buffer);
      void* buffer_data = helper.GetData(o3d::Buffer::WRITE_ONLY);
      if (!buffer_data) {
        O3D_ERROR(buffer->service_locator())
            << "could not lock buffer";
        return false;
      }

      unsigned element_offset = 0;
      // for each field, copy the stuff out of the array.
      const o3d::FieldRefArray& fields = buffer->fields();
      for (unsigned ff = 0; ff < fields.size(); ++ff) {
        o3d::Field* field = fields[ff];
        field->SetFromUInt32s(&values[element_offset],
                              total_components,
                              0,
                              num_elements);
        element_offset += field->num_components();
      }
      return true;
    }
    void userglue_method_SetAt(o3d::IndexBuffer *buffer,
                               unsigned int start_index,
                               const std::vector<unsigned int> &values) {
      unsigned int total_components = buffer->total_components();
      size_t size = values.size();
      if (total_components == 0) {
        O3D_ERROR(buffer->service_locator())
            << "no fields are defined on the buffer";
        return;
      }
      if (size % total_components != 0) {
        O3D_ERROR(buffer->service_locator())
            << "the number of values passed in is not a multiple of the number"
            << " of components in the fields on the buffer.";
        return;
      }

      unsigned num_elements_to_set = size / total_components;
      unsigned last_element = start_index + num_elements_to_set;
      if (last_element > buffer->num_elements() ||
          last_element < start_index) {
        O3D_ERROR(buffer->service_locator())
           << "Attempt to set elements outside of Buffer";
        return;
      }

      o3d::BufferLockHelper helper(buffer);
      void* buffer_data = helper.GetData(o3d::Buffer::WRITE_ONLY);
      if (!buffer_data) {
        O3D_ERROR(buffer->service_locator())
            << "could not lock buffer";
        return;
      }

      unsigned element_offset = 0;
      // for each field, copy the stuff out of the array.
      const o3d::FieldRefArray& fields = buffer->fields();
      for (unsigned ff = 0; ff < fields.size(); ++ff) {
        o3d::Field* field = fields[ff];
        field->SetFromUInt32s(&values[element_offset],
                              total_components,
                              start_index,
                              num_elements_to_set);
        element_offset += field->num_components();
      }
    }
  %}
};

}  // namespace o3d