#include <stdio.h>
#include <stdlib.h>      /* atol, strtol   */
#include <string.h>      /* strncmp, strstr,strchr */
#include <ctype.h>       /* isdigit */
#include <sys/stat.h>    /* stat */
#include <unistd.h>      /* stat */

#include <sys/sysinfo.h> /* sysinfo() */

#include "../sysinfo.h"
#include "../include/uname.h"


	/* This code originally modeled on linux sh-utils 1.16 uptime.c code */
	/* breaks for uptimes of over 2^31 seconds.  Is that a problem? */
int get_uptime (void) {

	FILE *fff;
	float exact_uptime;
	int uptime_seconds=-1;
	int result;

	fff=fopen("/proc/uptime","r");
	if (fff!=NULL) {
		result=fscanf(fff,"%f",&exact_uptime);
		fclose (fff);

		if (result==1) {
			uptime_seconds=exact_uptime;
		}
	}

	return uptime_seconds;
}

	/* Based on code contributed by */
	/* Anders Rundegren <anders@rundegren.com> */
int get_load_average(float *load_1,float *load_5,float *load_15) {

	FILE *fff;
	int result=-1;

	fff=fopen("/proc/loadavg","r");
	if (fff!=NULL) {
		result=fscanf(fff,"%f" "%f" "%f", load_1, load_5, load_15);
		fclose (fff);
		if (result!=3) {
			result=-1;
		}
	}

	return result;
}

int get_os_info(struct os_info_type *os_info) {
	return uname_get_os_info(os_info);
}

char *get_host_name(char *hostname,char *domain) {
	return uname_get_host_name(hostname,domain);
}


	/* This is a newer method to obtain memory info from /proc/iomem memory
	 * map under 2.4.x. It should work with ACPI systems too. */
	/* Originally Contributed by Sitsofe Wheeler <sits@sucs.swan.ac.uk> */
	/* Improved a bit (in theory) to handle 64-bit machines -vmw */

	/* Modern systems are zeroing out the addresses in */
	/* /proc/iomem for security reasons, which makes this useless */

long long get_mem_size_iomem(void) {

	unsigned long long mem_size=0,begin,end;
	char *pos;
	char temp_string[BUFSIZ];
	FILE *info;

	if ((info=fopen("/proc/iomem", "r"))) {
		while (fgets(temp_string, BUFSIZ, info)) {
			pos=strchr(temp_string, ':');
			/* It's safe to +1 to pos because in the worst case */
			/* we will be on the end of string marker. I just   */
			/* hope strncmp does bounds checking */
			if (pos && (strncmp(pos+1, " System RAM", 10)==0 ||
				strncmp(pos+1, " ACPI", 5)==0)) {
					/* Extract the upper memory position */
					/* printf("Adding %s region ",pos); */
				pos = strchr(temp_string, '-');
				if (pos) {
					*pos=0;
					end=strtoull(pos+1, NULL, 16);
					begin=strtoull(temp_string,NULL,16);
					mem_size+=(end-begin);
					/* printf("%lld bytes\n",(end-begin)); */
				}
			}
		}
		fclose(info);
		/* printf("Final size=%lld\n",mem_size); */
	}

	if (mem_size > 0) {

		/* if over, round up */
		if (mem_size%(1024*1024)) {
			mem_size = (mem_size/(1024*1024))+1;
		}
		else {
			mem_size = (mem_size/(1024*1024));
		}

		return mem_size;
	}
	else {
		return 0;
	}
}


	/* mem_size in megabytes by statting /proc/kcore */
	/* This won't work on 32bit machines with > 2Gig of RAM */
long long get_mem_size_stat(void) {

	long long mem_size=0;
	struct stat buff;

	stat("/proc/kcore",&buff);
	mem_size=buff.st_size;
	mem_size/=(1024*1024);

	return mem_size;
}

long long get_mem_size_sysinfo(void) {

	long long mem_size=0;
	struct sysinfo system_info;

	sysinfo(&system_info);

	mem_size=(system_info.totalram*system_info.mem_unit)/(1024*1024);

	return mem_size;

}

	/* get mem size from /proc/meminfo */
long long get_mem_size_meminfo(void) {

	long long mem_size=0;
	char temp_string[BUFSIZ];
	FILE *info;
	int position=0;

	info=fopen("/proc/meminfo", "r");

	if (info==NULL) {
		printf("Error opening /proc/meminfo!\n");
		return 0;
	}

	while (fgets(temp_string, BUFSIZ, info)) {
		position=0;
		/* Skip label */
		while (temp_string[position]) {
			if (isdigit(temp_string[position])) break;
			position++;
		}

		/* Grab values (in kb) */
		if (strstr(temp_string, "MemTotal")) {
			mem_size = atoll(temp_string+position);
		}
	}
	fclose(info);

	return mem_size/1024ULL;
}


	/* Try to intelligently figure out which memory method is best */
	/* /proc/iomem used to give the closest to the "expected" */
	/* value but is mostly useless now due to security reasons */

long long get_mem_size(void) {

	long long mem_size=0;

	/* First try any arch-specific memsize functions */
	mem_size=get_arch_specific_mem_size();

	if (mem_size == MEM_USE_MEMINFO) {
		mem_size = 0;
		goto use_meminfo;
	}

	if (mem_size == MEM_USE_SYSINFO) {
		mem_size = 0;
		goto use_sysinfo;
	}

	/* Next try the 2.4.x+ method of iomem */
	/* This breaks on moden (5.x?) systems */
	if (mem_size == 0) {
		mem_size = get_mem_size_iomem();
	}

#if 0
	/* Try stat-ing /proc/kcore */
	/* On modern 64-bit kernels this is 128TB in size? */
	if (mem_size == 0) {
		mem_size = get_mem_size_stat();
	}
#endif

use_sysinfo:

	/* sysinfo should return same as /proc/meminfo */
	/* which, sadly, is often from 1MB-20MB off    */
	if (mem_size == 0) {
		mem_size = get_mem_size_sysinfo();
	}

use_meminfo:
	/* If all else fails, try using /proc/meminfo */
	if (mem_size == 0) {
		mem_size = get_mem_size_meminfo();
	}

	return mem_size;
}

double get_cpu_mhz(void) {

	struct cpu_info_type cpu_info;
	double megahertz=0.0;
	long long temp;
	FILE *fff;

	fff=fopen("/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq","r");
	if (fff!=NULL) {
		if (fscanf(fff,"%lld",&temp) != 1)
		  temp=0;
		megahertz=(double)temp;
		megahertz/=1000.0;
		fclose(fff);
	}

	if (megahertz==0.0) {
		/* Couldn't read from cpufreq, instead use /proc/cpuinfo */

		get_cpu_info(&cpu_info);

		megahertz=(double)cpu_info.megahertz;
	}

	return megahertz;
}