#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <time.h>
#include <unistd.h>
#include <sys/types.h>
#include <ifaddrs.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netdb.h>
#include <linux/if_link.h>
#include <signal.h>

#include "spilcd_gfx.h"
#include "spilcd_font.h"
#include "base.h"


#define NI_MAXHOST 1025 
#define NI_MAXSERV 32

volatile sig_atomic_t done = 0;
struct sigaction action;

/**
 * 
 * @return 
 */
float GetCPULoad() {
    int FileHandler;
    char FileBuffer[1024];
    float load;

    FileHandler = open("/proc/loadavg", O_RDONLY);
    if(FileHandler < 0) {
        return -1; }
    read(FileHandler, FileBuffer, sizeof(FileBuffer) - 1);
    sscanf(FileBuffer, "%f", &load);
    close(FileHandler);
    return load;
}

/**
 * 
 * @return 
 */
float GetMemUsage() {
    int FileHandler;
    char FileBuffer[1024];
    int memTotal, memFree, memAvail, memBuf,memCached;
    float result;
    FileHandler = open("/proc/meminfo", O_RDONLY);
    if(FileHandler < 0) {
        return -1; }
    read(FileHandler, FileBuffer, sizeof(FileBuffer) - 1);
    sscanf(FileBuffer, "MemTotal:         %d kB\n MemFree:          %d kB\n MemAvailable:          %d kB\n Buffers:           %d kB\n Cached:           %d kB",
     &memTotal, &memFree, &memAvail, &memBuf, &memCached);
    close(FileHandler);
    result = 1.0 - (float)(memFree + memCached) / memTotal;
    return result;
}
/**
 * 
 * @return 
 */
int GetCPUTemp() {
   int FileHandler;
   char FileBuffer[1024];
   int CPU_temp;
   FileHandler = open("/sys/devices/virtual/thermal/thermal_zone0/temp", O_RDONLY);
   if(FileHandler < 0) {
      return -1; }
   read(FileHandler, FileBuffer, sizeof(FileBuffer) - 1);
   sscanf(FileBuffer, "%d", &CPU_temp);
   close(FileHandler);
   return CPU_temp / 1000;
}

void sig_handler(int signo)
{
    done = 1;
    printf("received signo :%d \n", signo);
}


/*
 * 
 */
int main(int argc, char** argv) {
    time_t mytime;
    struct tm *tm;
    uint8_t time_buffer[80];
    uint8_t text_buffer[100];    
    struct ifaddrs *ifaddr, *ifa;
    int family, s, n, row;
    char host[NI_MAXHOST];

    
    // Print pid, so that we can send signals from other shells
    printf("My pid is: %d\n", getpid());    
    memset(&action, 0, sizeof(struct sigaction));
    action.sa_handler = sig_handler;
    // Intercept SIGHUP and SIGINT
    if (sigaction(SIGINT, &action, NULL) == -1) {
        perror("Error: cannot handle SIGINT"); // Should not happen
    }
    if (sigaction(SIGTERM, &action, NULL) == -1) {
        perror("Error: cannot handle SIGTERM"); // Should not happen
    }

    lcd_t* lcd = demo_init();

    int rowy = 10;
    while (done == 0) {
        row = 0;

	// Date and Time
        mytime = time(NULL);
        tm = localtime (&mytime);
	lcd_fillScreen(lcd, 0, 0, 0);
        strftime(time_buffer, 80,"    %H:%M:%S", tm);
	lcd_drawText(lcd, 0, row * rowy, time_buffer, 255, 255, 255);
        row++;
        strftime(time_buffer, 80,"    %x", tm);
	lcd_drawText(lcd, 0, row * rowy, time_buffer, 200, 200, 200);
        row++;
        row++;

	// CPU
        float c = GetCPULoad() ;
	lcd_drawText(lcd, 0, row * rowy, "CPU load:", 255, 255, 100);
        row++;
        snprintf(text_buffer, sizeof(text_buffer), " %0.2f", c);
        printf("CPU load avg: %s\n", text_buffer);
	if (c < 0.2) {
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 50, 255, 50);
	} else if (c < 0.5) {
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 255, 255, 50);
	} else {
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 255, 50, 50);
	}
        row++;
        
        /* Memory usage */
        float m = GetMemUsage();
        snprintf(text_buffer, sizeof(text_buffer), " %3.0f%%", m*100);
        printf("Mem used: %s\n", text_buffer);
	lcd_drawText(lcd, 0, row * rowy, "Mem used:", 150, 150, 255);
	row++;
	lcd_drawText(lcd, 0, row * rowy, text_buffer, 255, 255, 255);
        //ssd1306DrawRect(0, 0, 127, 13, INVERSE, LAYER0);
        //ssd1306FillRect(2, 2, (int)(123 * m), 9, INVERSE, LAYER0);
	row++;
        
        /* CPU temperature  */
        int t = GetCPUTemp() ;
        snprintf ( text_buffer, sizeof(text_buffer), "%3d C", t );
        printf("CPU temp: %s\n", text_buffer);
	lcd_drawText(lcd, 0, row * rowy, "CPU temp:", 255, 180, 170);
        row++;
	if (t < 20) {
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 150, 150, 255);
	} else if (t < 25) {
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 150, 255, 150);
	} else if (t < 30) {
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 255, 255, 100);
	} else if (t < 35) {
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 255, 120, 100);
	} else {
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 255, 80, 20);
	}
        row++;

	// Network devices and IPs
        if (getifaddrs(&ifaddr) == -1) 
        {
            perror("getifaddrs");
            exit(EXIT_FAILURE);
        }
        for (ifa = ifaddr, n = 0; ifa != NULL; ifa = ifa->ifa_next, n++) {
            if (ifa->ifa_addr == NULL)
                continue;
            
            family = ifa->ifa_addr->sa_family;
            if ((strncmp ("eth", ifa->ifa_name, 3 ) == 0) && family == AF_INET) {
                s = getnameinfo(ifa->ifa_addr,
                       (ifa->ifa_addr->sa_family == AF_INET) ? sizeof(struct sockaddr_in) :
                                             sizeof(struct sockaddr_in6),
                       host, NI_MAXHOST,
                       NULL, 0, NI_NUMERICHOST);
                if (s != 0) {
                   printf("getnameinfo() failed: %s\n", gai_strerror(s));
                   exit(EXIT_FAILURE);
                }
                printf("%-8s <%s>\n", ifa->ifa_name, host);
                snprintf ( text_buffer, sizeof(text_buffer), "%s:", ifa->ifa_name);
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 200, 200, 255);
                row++;
                snprintf ( text_buffer, sizeof(text_buffer), " %s", host );
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 200, 255, 200);
                row++;
            } 
            if ((strncmp ("wlan", ifa->ifa_name, 4 ) == 0) && family == AF_INET) {
                s = getnameinfo(ifa->ifa_addr,
                       (ifa->ifa_addr->sa_family == AF_INET) ? sizeof(struct sockaddr_in) :
                                             sizeof(struct sockaddr_in6),
                       host, NI_MAXHOST,
                       NULL, 0, NI_NUMERICHOST);
                if (s != 0) {
                   printf("getnameinfo() failed: %s\n", gai_strerror(s));
                   exit(EXIT_FAILURE);
                }
                printf("%-8s <%s>\n", ifa->ifa_name, host);
                snprintf ( text_buffer, sizeof(text_buffer), "%s:",ifa->ifa_name);
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 255, 200, 200);
                row++;
                snprintf ( text_buffer, sizeof(text_buffer), " %s", host );
		lcd_drawText(lcd, 0, row * rowy, text_buffer, 200, 255, 200);
                row++;
            } 
        }
        freeifaddrs(ifaddr);
        row++;
        
	lcd_redrawBuffer(lcd);
	sleep(1);
    }

	demo_deinit(lcd);
}