#include "kmeans.h"
#include <iostream>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <string>

#ifdef WIN
#include <windows.h>
#else
#include <pthread.h>
#include <sys/time.h>
double gettime() {
  struct timeval t;
  gettimeofday(&t, NULL);
  return t.tv_sec + t.tv_usec * 1e-6;
}
#endif

#ifdef NV
#include <oclUtils.h>
#else
#include <CL/cl.h>
#endif

#ifndef FLT_MAX
#define FLT_MAX 3.40282347e+38
#endif

#ifdef RD_WG_SIZE_0_0
#define BLOCK_SIZE RD_WG_SIZE_0_0
#elif defined(RD_WG_SIZE_0)
#define BLOCK_SIZE RD_WG_SIZE_0
#elif defined(RD_WG_SIZE)
#define BLOCK_SIZE RD_WG_SIZE
#else
#define BLOCK_SIZE 256
#endif

#ifdef RD_WG_SIZE_1_0
#define BLOCK_SIZE2 RD_WG_SIZE_1_0
#elif defined(RD_WG_SIZE_1)
#define BLOCK_SIZE2 RD_WG_SIZE_1
#elif defined(RD_WG_SIZE)
#define BLOCK_SIZE2 RD_WG_SIZE
#else
#define BLOCK_SIZE2 256
#endif

// local variables
static cl_context context;
static cl_command_queue cmd_queue;
static cl_device_type device_type;
static cl_device_id *device_list;
static cl_int num_devices;

static int initialize(int use_gpu) {
  cl_int result;
  size_t size;

  /*// create OpenCL context
  cl_platform_id platform_id;
  if (clGetPlatformIDs(1, &platform_id, NULL) != CL_SUCCESS) {
    printf("ERROR: clGetPlatformIDs(1,*,0) failed\n");
    return -1;
  }
  cl_context_properties ctxprop[] = {CL_CONTEXT_PLATFORM,
                                     (cl_context_properties)platform_id, 0};
  device_type = use_gpu ? CL_DEVICE_TYPE_GPU : CL_DEVICE_TYPE_CPU;
  context = clCreateContextFromType(ctxprop, device_type, NULL, NULL, NULL);
  if (!context) {
    printf("ERROR: clCreateContextFromType(%s) failed\n",
           use_gpu ? "GPU" : "CPU");
    return -1;
  }

  // get the list of GPUs
  result = clGetContextInfo(context, CL_CONTEXT_DEVICES, 0, NULL, &size);
  num_devices = (int)(size / sizeof(cl_device_id));

  if (result != CL_SUCCESS || num_devices < 1) {
    printf("ERROR: clGetContextInfo() failed\n");
    return -1;
  }
  device_list = new cl_device_id[num_devices];
  if (!device_list) {
    printf("ERROR: new cl_device_id[] failed\n");
    return -1;
  }
  result =
      clGetContextInfo(context, CL_CONTEXT_DEVICES, size, device_list, NULL);
  if (result != CL_SUCCESS) {
    printf("ERROR: clGetContextInfo() failed\n");
    return -1;
  }*/

  cl_platform_id platform_id;
  num_devices = 1;
  device_list = new cl_device_id[num_devices];

  result = clGetPlatformIDs(1, &platform_id, NULL);
  result = clGetDeviceIDs(platform_id, CL_DEVICE_TYPE_DEFAULT, 1, device_list, NULL);
  context = clCreateContext(NULL, 1, device_list, NULL, NULL,  &result);

  // create command queue for the first device
  cmd_queue = clCreateCommandQueue(context, device_list[0], 0, NULL);
  if (!cmd_queue) {
    printf("ERROR: clCreateCommandQueue() failed\n");
    return -1;
  }

  return 0;
}

static int shutdown() {
  // release resources
  if (cmd_queue)
    clReleaseCommandQueue(cmd_queue);
  if (context)
    clReleaseContext(context);
  if (device_list)
    delete device_list;

  // reset all variables
  cmd_queue = 0;
  context = 0;
  device_list = 0;
  num_devices = 0;
  device_type = 0;

  return 0;
}

cl_mem d_feature;
cl_mem d_feature_swap;
cl_mem d_cluster;
cl_mem d_membership;

cl_kernel kernel;
cl_kernel kernel_s;
cl_kernel kernel2;

int *membership_OCL;
int *membership_d;
float *feature_d;
float *clusters_d;
float *center_d;

	
static int read_kernel_file(const char* filename, uint8_t** data, size_t* size) {
  if (nullptr == filename || nullptr == data || 0 == size)
    return -1;

  FILE* fp = fopen(filename, "r");
  if (NULL == fp) {
    fprintf(stderr, "Failed to load kernel.");
    return -1;
  }
  fseek(fp , 0 , SEEK_END);
  long fsize = ftell(fp);
  rewind(fp);

  *data = (uint8_t*)malloc(fsize);
  *size = fread(*data, 1, fsize, fp);
  
  fclose(fp);
  
  return 0;
}


int allocate(int n_points, int n_features, int n_clusters, float **feature) {
  /*int sourcesize = 1024 * 1024;
  char *source = (char *)calloc(sourcesize, sizeof(char));
  if (!source) {
    printf("ERROR: calloc(%d) failed\n", sourcesize);
    return -1;
  }

  // read the kernel core source
  char *tempchar = "./kmeans.cl";
  FILE *fp = fopen(tempchar, "rb");
  if (!fp) {
    printf("ERROR: unable to open '%s'\n", tempchar);
    return -1;
  }
  fread(source + strlen(source), sourcesize, 1, fp);
  fclose(fp);*/

  // OpenCL initialization
  int use_gpu = 1;
  if (initialize(use_gpu))
    return -1;

  // compile kernel
  cl_int err = 0;
  //const char *slist[2] = {source, 0};
  //cl_program prog = clCreateProgramWithSource(context, 1, slist, NULL, &err);
  cl_program prog = clCreateProgramWithBuiltInKernels(context, 1, device_list, "kmeans_kernel_c;kmeans_swap", &err);       
  if (err != CL_SUCCESS) {
    printf("ERROR: clCreateProgramWithSource() => %d\n", err);
    return -1;
  }
  err = clBuildProgram(prog, 0, NULL, NULL, NULL, NULL);
  { // show warnings/errors
    //	static char log[65536]; memset(log, 0, sizeof(log));
    //	cl_device_id device_id = 0;
    //	err = clGetContextInfo(context, CL_CONTEXT_DEVICES, sizeof(device_id),
    //&device_id, NULL);
    //	clGetProgramBuildInfo(prog, device_id, CL_PROGRAM_BUILD_LOG,
    // sizeof(log)-1, log, NULL);
    //	if(err || strstr(log,"warning:") || strstr(log, "error:"))
    // printf("<<<<\n%s\n>>>>\n", log);
  }
  if (err != CL_SUCCESS) {
    printf("ERROR: clBuildProgram() => %d\n", err);
    return -1;
  }

  char *kernel_kmeans_c = "kmeans_kernel_c";
  char *kernel_swap = "kmeans_swap";

  kernel_s = clCreateKernel(prog, kernel_kmeans_c, &err);
  if (err != CL_SUCCESS) {
    printf("ERROR: clCreateKernel() 0 => %d\n", err);
    return -1;
  }
  kernel2 = clCreateKernel(prog, kernel_swap, &err);
  if (err != CL_SUCCESS) {
    printf("ERROR: clCreateKernel() 0 => %d\n", err);
    return -1;
  }

  clReleaseProgram(prog);

  d_feature = clCreateBuffer(context, CL_MEM_READ_WRITE,
                             n_points * n_features * sizeof(float), NULL, &err);
  if (err != CL_SUCCESS) {
    printf("ERROR: clCreateBuffer d_feature (size:%d) => %d\n",
           n_points * n_features, err);
    return -1;
  }
  d_feature_swap =
      clCreateBuffer(context, CL_MEM_READ_WRITE,
                     n_points * n_features * sizeof(float), NULL, &err);
  if (err != CL_SUCCESS) {
    printf("ERROR: clCreateBuffer d_feature_swap (size:%d) => %d\n",
           n_points * n_features, err);
    return -1;
  }
  d_cluster =
      clCreateBuffer(context, CL_MEM_READ_WRITE,
                     n_clusters * n_features * sizeof(float), NULL, &err);
  if (err != CL_SUCCESS) {
    printf("ERROR: clCreateBuffer d_cluster (size:%d) => %d\n",
           n_clusters * n_features, err);
    return -1;
  }
  d_membership = clCreateBuffer(context, CL_MEM_READ_WRITE,
                                n_points * sizeof(int), NULL, &err);
  if (err != CL_SUCCESS) {
    printf("ERROR: clCreateBuffer d_membership (size:%d) => %d\n", n_points,
           err);
    return -1;
  }

  // write buffers
  err = clEnqueueWriteBuffer(cmd_queue, d_feature, 1, 0,
                             n_points * n_features * sizeof(float), feature[0],
                             0, 0, 0);
  if (err != CL_SUCCESS) {
    printf("ERROR: clEnqueueWriteBuffer d_feature (size:%d) => %d\n",
           n_points * n_features, err);
    return -1;
  }

  clSetKernelArg(kernel2, 0, sizeof(void *), (void *)&d_feature);
  clSetKernelArg(kernel2, 1, sizeof(void *), (void *)&d_feature_swap);
  clSetKernelArg(kernel2, 2, sizeof(cl_int), (void *)&n_points);
  clSetKernelArg(kernel2, 3, sizeof(cl_int), (void *)&n_features);

  size_t global_work[3] = {n_points, 1, 1};
  /// Ke Wang adjustable local group size 2013/08/07 10:37:33
  size_t local_work_size = BLOCK_SIZE; // work group size is defined by
                                       // RD_WG_SIZE_0 or RD_WG_SIZE_0_0
                                       // 2014/06/10 17:00:51
  if (global_work[0] % local_work_size != 0)
    global_work[0] = (global_work[0] / local_work_size + 1) * local_work_size;

  err = clEnqueueNDRangeKernel(cmd_queue, kernel2, 1, NULL, global_work,
                               &local_work_size, 0, 0, 0);
  if (err != CL_SUCCESS) {
    printf("ERROR: clEnqueueNDRangeKernel()=>%d failed\n", err);
    return -1;
  }

  membership_OCL = (int *)malloc(n_points * sizeof(int));
}

void deallocateMemory() {
  clReleaseMemObject(d_feature);
  clReleaseMemObject(d_feature_swap);
  clReleaseMemObject(d_cluster);
  clReleaseMemObject(d_membership);
  free(membership_OCL);
}

int main(int argc, char **argv) {
  printf("WG size of kernel_swap = %d, WG size of kernel_kmeans = %d \n",
         BLOCK_SIZE, BLOCK_SIZE2);
  setup(argc, argv);
  shutdown();
}

int kmeansOCL(float **feature, /* in: [npoints][nfeatures] */
              int n_features, int n_points, int n_clusters, int *membership,
              float **clusters, int *new_centers_len, float **new_centers) {

  int delta = 0;
  int i, j, k;
  cl_int err = 0;

  size_t global_work[3] = {n_points, 1, 1};

  /// Ke Wang adjustable local group size 2013/08/07 10:37:33
  size_t local_work_size = BLOCK_SIZE2; // work group size is defined by
                                        // RD_WG_SIZE_1 or RD_WG_SIZE_1_0
                                        // 2014/06/10 17:00:41
  if (global_work[0] % local_work_size != 0)
    global_work[0] = (global_work[0] / local_work_size + 1) * local_work_size;

  err = clEnqueueWriteBuffer(cmd_queue, d_cluster, 1, 0,
                             n_clusters * n_features * sizeof(float),
                             clusters[0], 0, 0, 0);
  if (err != CL_SUCCESS) {
    printf("ERROR: clEnqueueWriteBuffer d_cluster (size:%d) => %d\n", n_points,
           err);
    return -1;
  }

  int size = 0;
  int offset = 0;

  clSetKernelArg(kernel_s, 0, sizeof(void *), (void *)&d_feature_swap);
  clSetKernelArg(kernel_s, 1, sizeof(void *), (void *)&d_cluster);
  clSetKernelArg(kernel_s, 2, sizeof(void *), (void *)&d_membership);
  clSetKernelArg(kernel_s, 3, sizeof(cl_int), (void *)&n_points);
  clSetKernelArg(kernel_s, 4, sizeof(cl_int), (void *)&n_clusters);
  clSetKernelArg(kernel_s, 5, sizeof(cl_int), (void *)&n_features);
  clSetKernelArg(kernel_s, 6, sizeof(cl_int), (void *)&offset);
  clSetKernelArg(kernel_s, 7, sizeof(cl_int), (void *)&size);

  err = clEnqueueNDRangeKernel(cmd_queue, kernel_s, 1, NULL, global_work,
                               &local_work_size, 0, 0, 0);
  if (err != CL_SUCCESS) {
    printf("ERROR: clEnqueueNDRangeKernel()=>%d failed\n", err);
    return -1;
  }
  clFinish(cmd_queue);
  err = clEnqueueReadBuffer(cmd_queue, d_membership, 1, 0,
                            n_points * sizeof(int), membership_OCL, 0, 0, 0);
  if (err != CL_SUCCESS) {
    printf("ERROR: Memcopy Out\n");
    return -1;
  }

  delta = 0;
  for (i = 0; i < n_points; i++) {
    int cluster_id = membership_OCL[i];
    new_centers_len[cluster_id]++;
    if (membership_OCL[i] != membership[i]) {
      delta++;
      membership[i] = membership_OCL[i];
    }
    for (j = 0; j < n_features; j++) {
      new_centers[cluster_id][j] += feature[i][j];
    }
  }

  return delta;
}