/*
    This sketch demonstrates how to scan WiFi networks.
    The API is almost the same as with the WiFi Shield library,
    the most obvious difference being the different file you need to include:
*/
#include "ESP8266WiFi.h"
#include <Arduino.h>
#include <U8g2lib.h>

#ifdef U8X8_HAVE_HW_SPI
#include <SPI.h>
#endif
#ifdef U8X8_HAVE_HW_I2C
#include <Wire.h>
#endif

U8G2_SSD1306_128X32_UNIVISION_F_HW_I2C u8g2(U8G2_R0, /* reset=*/ 16, /* clock=*/ 5, /* data=*/ 4);
ADC_MODE(ADC_VCC);

void setup() {
  Serial.begin(115200);

  // sceen stuff
  pinMode(10, OUTPUT);
  pinMode(9, OUTPUT);
  digitalWrite(10, 0);
  digitalWrite(9, 0);   
  u8g2.begin();  
  u8g2.enableUTF8Print(); 

  Serial.println("Setup done");

  getBatteryLevel();

  // Set WiFi to station mode and disconnect from an AP if it was previously connected
  WiFi.mode(WIFI_STA);
  WiFi.disconnect();
  delay(100);
}

void getBatteryLevel() { 
  u8g2.setFont(u8g2_font_8x13_mf); 
  
  uint32_t getVcc = ESP.getVcc();
  Serial.println(getVcc);

  // printing getVcc to screen
  /*
  String batvol2 = "";
  batvol2 += getVcc;
  char batChr[batvol2.length()+1]; 
  batvol2.toCharArray(batChr, batvol2.length()+1);
  u8g2.drawStr(0,10,batChr);
  */

  float measuredvbat = getVcc; // for actual voltage
  measuredvbat /= 1024; // convert to voltage 
  Serial.println(measuredvbat);

  //printing actual votage to screen
  /*
  String batvol = "";
  batvol += measuredvbat;
  char batChr2[batvol.length()+1]; 
  batvol.toCharArray(batChr2, batvol.length()+1);
  u8g2.drawStr(0,20,batChr2);
  */
 
  int percent = map(getVcc, 2300, 3000, 1, 11); // turn vcc into batt perentage (yea I know it's not that accurate due to dropoff rate)
  if(percent > 11){ percent = 11; }
  if(percent < 1){ percent = 1; }
  
  u8g2.setFont(u8g_font_unifont);
  //u8g.setFont(u8g_font_osb21);
  u8g2.drawFrame(111,24,15,8);
  u8g2.drawBox(113,26,percent,4); //3rd param is %(1-11)
  u8g2.drawBox(126,26,2,4);
 
}

void drawScrollString(int16_t offset, const char *s){
  static char buf[36];  // should for screen with up to 256 pixel width 
  size_t len;
  size_t char_offset = 0;
  u8g2_uint_t dx = 0;
  size_t visible = 0;
  
  u8g2.setDrawColor(0);   // clear the scrolling area
  u8g2.drawBox(0, 30, u8g2.getDisplayWidth()-1, u8g2.getDisplayHeight()-1);
  u8g2.setDrawColor(1);   // set the color for the text
    
  len = strlen(s);
  if ( offset < 0 )
  {
    char_offset = (-offset)/8;
    dx = offset + char_offset*8;
    if ( char_offset >= u8g2.getDisplayWidth()/8 )
      return;
    visible = u8g2.getDisplayWidth()/8-char_offset+1;
    strncpy(buf, s, visible);
    buf[visible] = '\0';
    u8g2.setFont(u8g2_font_6x10_mf);
    u8g2.drawStr(char_offset*8-dx, 30, buf);
  }
  else
  {
    char_offset = offset / 8;
    if ( char_offset >= len )
      return; // nothing visible
    dx = offset - char_offset*8;
    visible = len - char_offset;
    if ( visible > u8g2.getDisplayWidth()/8+1 )
      visible = u8g2.getDisplayWidth()/8+1;
    strncpy(buf, s+char_offset, visible);
    buf[visible] = '\0';
    u8g2.setFont(u8g2_font_6x10_mf);
    u8g2.drawStr(-dx, 30, buf);
  }
  
}

void loop() {
  //u8g2.clearBuffer(); // only need this if you want "scanning..." on a clear screen!

  int16_t offset = -(int16_t)u8g2.getDisplayWidth();
  int16_t len = strlen("Scanning...");
  for(;;)              // then do the scrolling
  {
  
    drawScrollString(offset, "Scanning...");        // no clearBuffer required, screen will be partially cleared here
    getBatteryLevel();
    u8g2.sendBuffer();        // transfer internal memory to the display

    delay(20);
    offset+=2;
    if ( offset > len*8+1 )
      break;
  }
  u8g2.sendBuffer();
  
  Serial.println("scan start");

  // WiFi.scanNetworks will return the number of networks found
  int n = WiFi.scanNetworks();
  Serial.println("scan done");
  if (n == 0) {
    Serial.println("no networks found");
  } else {
    Serial.print(n);
    Serial.println(" networks found");
    
    for (int i = 0; i < n; ++i) {
      // Print SSID and RSSI for each network found
      Serial.print(i + 1);
      Serial.print(": ");
      Serial.print(WiFi.SSID(i));

      u8g2.clearBuffer();
      u8g2.setFont(u8g2_font_8x13_mf);
      char ssid[WiFi.SSID(i).length()+1]; 
      WiFi.SSID(i).toCharArray(ssid, WiFi.SSID(i).length()+1);
      u8g2.drawStr(0,9,ssid);
      u8g2.print(WiFi.SSID(i));
      
      Serial.print(" (");
      Serial.print(WiFi.RSSI(i));
      Serial.print(")");
      Serial.println((WiFi.encryptionType(i) == ENC_TYPE_NONE) ? " " : "*");
      u8g2.setFont(u8g2_font_6x12_mf);

      switch(WiFi.encryptionType(i)){
        case ENC_TYPE_NONE:
          u8g2.drawStr(0,21,"Open"); 
          break;
        case ENC_TYPE_WEP:
          u8g2.drawStr(0,21,"WEP"); 
          break;
        case ENC_TYPE_TKIP:
          u8g2.drawStr(0,21,"WPA/PSK"); 
          break;
        case ENC_TYPE_CCMP:
          u8g2.drawStr(0,21,"WPA2/PSK"); 
          break;
        case ENC_TYPE_AUTO:
          u8g2.drawStr(0,21,"WPA/WPA2/PSK"); 
          break;
        default:
          u8g2.drawStr(0,21,"Unknown Encryption"); 
          break;
      }

      u8g2.setFont(u8g2_font_6x10_mf);
      String chStr = "";
      chStr += WiFi.channel(i);
      char chan[chStr.length()+1]; 
      chStr.toCharArray(chan, chStr.length()+1);
      
      String rssiStr = "";
      rssiStr += WiFi.RSSI(i);
      char rssi[rssiStr.length()+1]; 
      rssiStr.toCharArray(rssi, rssiStr.length()+1);
      String toWrite = "ch: "+chStr+" dB: "+rssiStr;
      
      char chrWrite[toWrite.length()+1]; 
      toWrite.toCharArray(chrWrite, toWrite.length()+1);
      
      u8g2.drawStr(0,32,chrWrite); 

      getBatteryLevel();
      
      u8g2.sendBuffer();
      delay(2000); // was 2000
    }
  }
  Serial.println("");

  // Wait a bit before scanning again
  delay(1000);
}