//---------------------------------------------------------------------------//
// Copyright (c) 2013-2014 Kyle Lutz <kyle.r.lutz@gmail.com>
//
// Distributed under the Boost Software License, Version 1.0
// See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt
//
// See http://boostorg.github.com/compute for more information.
//---------------------------------------------------------------------------//

#include <iostream>

// include the proper opencl header for the system
#if defined(__APPLE__)
#include <OpenCL/cl.h>
#else
#include <CL/cl.h>
#endif

// the opencl_test example displays the opencl platforms and devices found
// on the system using the opencl api directly. if this test fails to compile
// and/or run, there is a problem with the opencl implementation found on the
// system. users should ensure this test runs successfuly before using any of
// the boost.compute apis (which depend on a working opencl implementation).
int main()
{
    // query number of opencl platforms
    cl_uint num_platforms = 0;
    cl_int ret = clGetPlatformIDs(0, NULL, &num_platforms);
    if(ret != CL_SUCCESS){
        std::cerr << "failed to query platforms: " << ret << std::endl;
        return -1;
    }

    // check that at least one platform was found
    if(num_platforms == 0){
        std::cerr << "found 0 platforms" << std::endl;
        return 0;
    }

    // get platform ids
    cl_platform_id *platforms = new cl_platform_id[num_platforms];
    clGetPlatformIDs(num_platforms, platforms, NULL);

    // iterate through each platform and query its devices
    for(cl_uint i = 0; i < num_platforms; i++){
        cl_platform_id platform = platforms[i];

        // query number of opencl devices
        cl_uint num_devices = 0;
        ret = clGetDeviceIDs(platform, CL_DEVICE_TYPE_ALL, 0, NULL, &num_devices);
        if(ret != CL_SUCCESS){
            std::cerr << "failed to lookup devices for platform " << i << std::endl;
            continue;
        }

        // print number of devices found
        std::cout << "platform " << i << " has " << num_devices << " devices:" << std::endl;

        // get device ids for the platform
        cl_device_id *devices = new cl_device_id[num_devices];
        ret = clGetDeviceIDs(platform, CL_DEVICE_TYPE_ALL, num_devices, devices, NULL);
        if(ret != CL_SUCCESS){
            std::cerr << "failed to query platform devices" << std::endl;
            delete[] devices;
            continue;
        }

        // iterate through each device on the platform and print its name
        for(cl_uint j = 0; j < num_devices; j++){
            cl_device_id device = devices[j];

            // get length of the device name string
            size_t name_length = 0;
            ret = clGetDeviceInfo(device, CL_DEVICE_NAME, 0, NULL, &name_length);
            if(ret != CL_SUCCESS){
                std::cerr << "failed to query device name length for device " << j << std::endl;
                continue;
            }

            // get the device name string
            char *name = new char[name_length];
            ret = clGetDeviceInfo(device, CL_DEVICE_NAME, name_length, name, NULL);
            if(ret != CL_SUCCESS){
                std::cerr << "failed to query device name string for device " << j << std::endl;
                delete[] name;
                continue;
            }

            // print out the device name
            std::cout << "  device: " << name << std::endl;

            delete[] name;
        }
        delete[] devices;
    }
    delete[] platforms;

    return 0;
}