#include "legato.h"
#include "util.h"

le_result_t readFromFile (const char *path, void *value,
  int (*scanCallback) (FILE *f, void *val)) {
  FILE *f = fopen(path, "r");
  if (f == NULL) {
    LE_WARN("Couldn't open '%s' - %m", path);
    return LE_IO_ERROR;
  }
  int numScanned = scanCallback(f, value);
  if (numScanned != 1) return LE_FORMAT_ERROR;
  fclose(f);
  return LE_OK;
}

int scanIntCallback (FILE *f, void *value) {
  int *val = value;
  return fscanf(f, "%d", val);
}

int scanDoubleCallback (FILE *f, void *value) {
  double *val = value;
  return fscanf(f, "%lf", val);
}

le_result_t ioutil_readIntFromFile (const char *path, int *value) {
  return readFromFile(path, value, scanIntCallback);
}

le_result_t ioutil_readDoubleFromFile (const char *path, double *value) {
  return readFromFile(path, value, scanDoubleCallback);
}

le_result_t ioutil_writeToFile (const char *path, void *value, size_t size, size_t count) {
  LE_INFO("Attempting to write to %s", path);
  FILE *f = fopen(path, "w");
  if (f == NULL) {
    LE_WARN("Failed to open %s for writing", path);
    return LE_IO_ERROR;
  }
  ssize_t nWritten = fwrite(value, size, count, f);
  LE_INFO("Wrote %d bytes", nWritten);
  fclose(f);
  return LE_OK;
}

le_result_t util_flattenRes (le_result_t *res, int nRes) {
  for (int i = 0; i < nRes; i++) {
    le_result_t *resPtr = res + i;
    if (*resPtr != LE_OK) return *resPtr;
  }
  return LE_OK;
}

int util_getUnixDatetime () {
  struct timeval tv;
  gettimeofday(&tv, NULL);
  return tv.tv_sec;
}

/**
 * Get the last modified datetime
 * of the file at path
 */
time_t util_getMTime (char *path) {
  struct stat st;
  if (stat(path, &st) != 0) return -1;
  else return st.st_mtime;
}

uint64_t GetCurrentTimestamp(void) {
  struct timeval tv;
  gettimeofday(&tv, NULL);
  uint64_t utcMilliSec = (uint64_t)(tv.tv_sec) * 1000 + (uint64_t)(tv.tv_usec) / 1000;
  return utcMilliSec;
}