// Copyright 2013 Google Inc. All Rights Reserved.
//
// Log - implemented using stdout.

#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "log.h"

namespace {

FILE* output_file = stdout;

}  // namespace

namespace wvcdm {

LogPriority g_cutoff = LOG_WARN;

void InitLogging(int argc, const char* const* argv) {
  // default to stdout if no arguments set it otherwise.
  output_file = stdout;

  for (int i = 1; i < argc; i++) {
    if (!strcmp(argv[i], "-v")) {
      g_cutoff = LOG_VERBOSE;
    } else if (!strcmp(argv[i], "-")) {
      // default above is stdout, so keep that.
    } else {
      // open a file for output.
      output_file = fopen(argv[i], "a");
      if (!output_file) {
        output_file = stdout;
        printf("Could not open log file \"%s\"\n", argv[i]);
      }
    }
  }

  const char *verbose_env = getenv("VERBOSE_LOG");
  if (verbose_env && ! strncmp(verbose_env, "yes", 3) ) {
    g_cutoff = LOG_VERBOSE;
  }
}

void Log(const char* file, int line, LogPriority level, const char* fmt, ...) {
  const char* severities[] = { "ERROR", "WARN", "INFO", "DEBUG", "VERBOSE" };
  if (level >= sizeof(severities) / sizeof(*severities)) {
    fprintf(output_file, "[FATAL:%s(%d)] Invalid log priority level: %d\n",
            file, line, level);
    return;
  }
  if (level > g_cutoff) return;

  fprintf(output_file, "[%s:%s(%d)] ", severities[level], file, line);

  va_list ap;
  va_start(ap, fmt);
  vfprintf(output_file, fmt, ap);
  va_end(ap);

  putc('\n', output_file);
  fflush(output_file);
}

};  // namespace wvcdm