// Copyright (C) 2015-2015 ChaosForge Ltd
// http://chaosforge.org/
//
// This file is part of Nova libraries. 
// For conditions of distribution and use, see copying.txt file in root folder.

#include "nv/engine/mesh_manager.hh"
#include "nv/formats/nmd_loader.hh"
#include "nv/io/c_file_system.hh"

using namespace nv;

resource< gpu_mesh > gpu_mesh_manager::create_resource( resource< data_channel_set > mesh )
{
	if ( auto lmesh = mesh.lock() )
	{
		gpu_mesh* gm = new gpu_mesh;
		gm->va = m_context->create_vertex_array( &*lmesh, STATIC_DRAW );
		gm->count = lmesh->get_channel_size( slot::INDEX );
		gm->shader = lmesh->get_channel( slot::BONEINDEX ) != nullptr ? BONE : DIRECT;
		return add( mesh.id(), gm );
	}
	return resource< gpu_mesh >();
}

void gpu_mesh_manager::release( gpu_mesh* m )
{
	m_context->release( m->va );
}

nv::resource< nv::data_channel_set > nv::mesh_data_manager::get_path( const string_view& path, resource< mesh_data > default /*= resource< mesh_data >()*/, data_node_info* info /*= nullptr */ )
{
	nv::resource< nv::mesh_data > mr = default;

	nv::string_view sub_mesh_name;
	nv::string128 base_mesh_name( path );
	nv::uint32 sub_mesh_pos = path.find( ":" );
	nv::uint32 dot_pos = path.find( "." );
	if ( sub_mesh_pos != nv::string_view::npos )
	{
		sub_mesh_name = path.substr( sub_mesh_pos + 1 );
		base_mesh_name.assign( path.substr( 0, sub_mesh_pos ) );
		NV_LOG_INFO( "Requested submesh - [", sub_mesh_name, "] in [", base_mesh_name, "]" );
	}

	if ( dot_pos != nv::string_view::npos )
	{
		mr = get( base_mesh_name );
	}
	else
	{
		sub_mesh_name = base_mesh_name;
	}

	if ( !mr )
	{
		NV_LOG_ERROR( "MESH FILE NOT FOUND - ", path );
		NV_ASSERT( false, "MESH FILE NOT FOUND!" );
		return nv::resource< nv::data_channel_set >();
	}

	if ( auto mdata = mr.lock() )
	{
		sint32 index = -1;
		if ( sub_mesh_name.empty() )
		{
			index = 0;
		}
		else if ( sub_mesh_name[0] >= '0' && sub_mesh_name[0] <= '9' )
		{
			index = nv::buffer_to_uint32( sub_mesh_name.data(), nullptr );
		}
		else
		{
			auto itr = mdata->names.find( sub_mesh_name );
			if ( itr != mdata->names.end() )
				index = itr->second;
		}
		if ( index >= 0 )
		{
			if ( info )
				*info = mdata->infos[index];
			return mdata->meshes[index];
		}

		NV_LOG_ERROR( "Resource path fail! - ", path );
		//NV_ASSERT( false, "Resource path fail!" );
	}
	else
	{
		NV_LOG_ERROR( "Resource lock fail! - ", path );
		//NV_ASSERT( false, "Resource lock fail!" );
	}
	return nv::resource< nv::data_channel_set >();
}

bool nv::mesh_data_manager::load_resource( const string_view& id )
{
	nmd_loader* loader = nullptr;
	c_file_system fs;
	stream* mesh_file = open_stream( fs, id );
	if ( !mesh_file ) return false;

	loader = new nmd_loader( m_strings );
	loader->load( *mesh_file );
	delete mesh_file;

	mesh_data* result = new mesh_data;
	result->node_data = loader->release_data_node_list();
	if ( result->node_data )
	{
		data_node_list* nd = result->node_data;
		for ( uint32 i = 0; i < nd->size(); ++i )
			result->node_names[(*nd)[i].name] = i;
	}
	
	resource< mesh_data > rmesh = add( id, result );

	for ( uint32 i = 0; i < loader->get_mesh_count(); ++i )
	{
		data_node_info info;
		data_channel_set* data = loader->release_mesh_data( i, info );
		result->infos.push_back( info );
		result->names[ info.name ] = i;
		auto mesh = m_mesh_manager->add( shash64( id.get_hash() + i ), data );
		result->meshes.push_back( mesh );
		m_source_map[mesh.id()] = mesh_source{ rmesh, i };
	}
	result->path.assign( id );
	delete loader;
	return result != nullptr;
}