/*
  A simple Pong game.
  https://github.com/eholk/Arduino-Pong/blob/master/pong.ino
*/

#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width,  in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

//Define buttons
#define UP_PIN 0 
#define DOWN_PIN 2 
#define OK_PIN 6 
#define LEFT_PIN 3
#define RIGHT_PIN 4

String state = "home";  //This variable changes with interfaces --- used for identifying the interface
String tested_state = "not tested"; //If the tested component is ok or not ok. Default is "not tested"
String retest_mode = "off";

int mode_selected = 0;  //This vriable is for store the mode(pin selection/BJT/Bluetooth) --- for choosing operating mode
int bjt_selected = 0;   //NPN or PNP 
int return_home = 0;    //This variable is for selecting Retest or Home

int page = 0; //used for breaking the IC list to pages
int ic_sel = 0; //used for going up and down in a ic page
int ic_ind;
int pin_number = 0;
int max_pages;

int status_of_test = 0;


String pin_4[20] = {"comp1", "comp2", "comp3", "comp4","comp5","comp6","comp7","comp8","comp9","comp10","comp11","comp12","comp13","comp14","comp15","comp16","comp17","comp18","comp19","comp20"};
String pin_6[20] = {"comp1", "comp2", "comp3", "comp4","comp5","comp6","comp7","comp8","comp9","comp10","comp11","comp12","comp13","comp14","comp15","comp16","comp17","comp18","comp19","comp20"};
String pin_8[20] = {"comp1", "comp2", "comp3", "comp4","comp5","comp6","comp7","comp8","comp9","comp10","comp11","comp12","comp13","comp14","comp15","comp16","comp17","comp18","comp19","comp20"};
String pin_12[20] = {"comp1", "comp2", "comp3", "comp4","comp5","comp6","comp7","comp8","comp9","comp10","comp11","comp12","comp13","comp14","comp15","comp16","comp17","comp18","comp19","comp20"};
String pin_14[20] = {"comp1", "comp2", "comp3", "comp4","comp5","comp6","comp7","comp8","comp9","comp10","comp11","comp12","comp13","comp14","comp15","comp16","comp17","comp18","comp19","comp20"};

// declare an SSD1306 display object connected to I2C
Adafruit_SSD1306 oled(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);


void setup() 
{   
    Serial.begin(9600);  
    
    pinMode(UP_PIN, INPUT_PULLUP);
    pinMode(DOWN_PIN, INPUT_PULLUP);
    pinMode(OK_PIN, INPUT_PULLUP);
    pinMode(LEFT_PIN, INPUT_PULLUP);
    pinMode(RIGHT_PIN, INPUT_PULLUP);


    // initialize OLED display with address 0x3C for 128x64
    if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
        Serial.println(F("SSD1306 allocation failed"));
        while (true);
    }

    delay(2000);         // wait for initializing
    oled.clearDisplay(); // clear display
    oled.setTextSize(2);          // text size
    oled.setTextColor(WHITE);     // text color
    oled.setCursor(20, 20);        // position to display
    oled.println("Welcome!"); // text to display
    oled.setTextSize(1);          // text size
    oled.setCursor(85, 55);        // position to display
    oled.println("CodeRed"); // text to display
    oled.display();               // show on OLED
    oled.clearDisplay(); // clear display
    delay (500);
}


void loop() 
{   
    int up_val = digitalRead(UP_PIN);
    int down_val = digitalRead(DOWN_PIN);
    int left_val = digitalRead(LEFT_PIN);
    int right_val = digitalRead(RIGHT_PIN);
    //int ok_val = digitalRead(OK_PIN);
    //Serial.println(ok_val);

    if (state == "home"){
        displayMenu();
        selectMenu();
    }

    if (state == " Pin Selection"){
        pinSelection();
        pinnumSelect();
    }
  
    if (state == " BJT"){
        //bjtModel();
        //bjtSelect();
    }

    if ((state == "ok") || (state == "not ok")){
        //testedOutput("BJT", right_val, left_val, ok_val);
    }

    if (state == "  4"){
        
        if (retest_mode == "on"){
            compOK();
            retest_mode = "off";
        }

        else if (tested_state == "tested"){
              homeorretest();
            }


        else{
            icPages(page, pin_4, 20);
            backFoward();
            int ok_val =digitalRead(OK_PIN);
            Serial.println(" OK:  " + String(ok_val));
            if (ok_val == 0){
              compOK();
            }

            
        }
        
        
      
    }
}


//this function is for homepage
void displayMenu()
{ 
    int up_val = digitalRead(UP_PIN);
    int down_val = digitalRead(DOWN_PIN);
    
    const char *modes[3] = {
      " Pin Selection",
      " BJT",
      " Bluetooth"
    };

    //Moving between modes
    if (up_val == 0){
      if (mode_selected == 0) {
        mode_selected  = 2;
      }
      else{
        mode_selected = mode_selected - 1;
      }
      delay(150);
    }

    else if (down_val == 0){
      if (mode_selected == 2) {
        mode_selected  = 0;
      }
      else{
        mode_selected = mode_selected + 1;
      }
      delay(150);
    }

    oled.clearDisplay();
    oled.setTextSize(1);
    oled.setTextColor(SSD1306_WHITE);
    oled.setCursor(0, 10);
    oled.println("Select the Mode");
    oled.setCursor(0, 25);

    for (int i = 0; i < 3; i++) {
      if (i == mode_selected){
        oled.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
        oled.println(modes[i]);
      }

      else{
        oled.setTextColor(SSD1306_WHITE);
        oled.println(modes[i]);
      }
    }

    oled.display();
}


//this function is for select item for home menu
void selectMenu()
{
  int ok_val = digitalRead(OK_PIN);

  const char *modes[3] = {
    " Pin Selection",
    " BJT",
    " Bluetooth"
  };

  if (ok_val == 0){
    oled.clearDisplay();
    oled.setTextSize(1);
    oled.setTextColor(SSD1306_WHITE);
    oled.setCursor(5,10);        
  
    oled.println("--"+String(modes[mode_selected])+" --");
    oled.display();
    state = modes[mode_selected]; //state changes to the mode
    delay(2000);
    mode_selected = 0;
  }
}

//this is for pin selection page
void pinSelection()
{ 

    int up_val = digitalRead(UP_PIN);
    int down_val = digitalRead(DOWN_PIN);

    const char *pin[5] = {
      "  4",
      "  6",
      "  8",
      " 12",
      " 16"
    };

    //Moving between modes
    if (up_val == 0){
      if (pin_number == 0) {
        pin_number  = 4;
        delay(100);
      }
      else{
        pin_number = pin_number - 1;
        delay(100);
      }
    }

    else if (down_val == 0){
      if (pin_number == 4) {
        pin_number  = 0;
        delay(100);
      }
      else{
        pin_number = pin_number + 1;
        delay(100);
      }
    }

    oled.clearDisplay();
    oled.setTextSize(1);
    oled.setTextColor(SSD1306_WHITE);
    oled.setCursor(0, 0);
    oled.println("Select the Number of Pins");
    oled.setCursor(0, 20);

    for (int i = 0; i < 5; i++) {
      if (i == pin_number){
        oled.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
        oled.println(pin[i]);
      }

      else{
        oled.setTextColor(SSD1306_WHITE);
        oled.println(pin[i]);
      }
      
    }
    oled.display();
}

//this is for selectig number of pins
void pinnumSelect()
{
    int ok_val = digitalRead(OK_PIN);

    const char *pin[5] = {
      "  4",
      "  6",
      "  8",
      " 12",
      " 16"
    };

    if (ok_val == 0){
      state = pin[pin_number];
    }

    delay(150);
}

//this is for bjt interface
void bjtModel(int up_val, int down_val)
{
    const char *bjt[2] = {
        "PNP",
        "NPN"
    };

    if ((up_val == 0)||(down_val == 0)){
      if (bjt_selected == 0){
        bjt_selected = 1;
      }
      else if (bjt_selected == 1){
        bjt_selected = 0;
      }
      delay(100);
    }
  
    if (bjt_selected == 0){
      oled.clearDisplay();
      oled.setTextSize(1);
      oled.setTextColor(SSD1306_WHITE);
      oled.setCursor(0, 10);
      oled.println("Select the BJT model");
      oled.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
      oled.setCursor(10, 30);
      oled.println("PNP");
      oled.setTextColor(SSD1306_WHITE);
      oled.setCursor(10, 45);
      oled.println("NPN");
      oled.display();
      delay(100);
    }

    else if (bjt_selected == 1){
      oled.clearDisplay();
      oled.setTextSize(1);
      oled.setTextColor(SSD1306_WHITE);
      oled.setCursor(0, 10);
      oled.println("Select the BJT model");
      oled.setTextColor(SSD1306_WHITE);
      oled.setCursor(10, 30);
      oled.println("PNP");
      oled.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
      oled.setCursor(10, 45);
      oled.println("NPN");
      oled.display();
      delay(100);
    }
}

//this is for select pnp/npn
void bjtSelect()
{
  int ok_val = digitalRead(OK_PIN);
  const char *bjt[2] = {
    "NPN",
    "PNP"
  };

  if (ok_val == 0){
    oled.clearDisplay();
    oled.setTextSize(1);
    oled.setTextColor(SSD1306_WHITE);
    oled.setCursor(0, 10);
    oled.println(bjt[bjt_selected]);
    oled.display();
    state = bjt[bjt_selected]; //state changes to the mode
    delay(100);
    bjt_selected = 0;
  }
}

//this is for connecting a device
/*void connectDevice(String component){
    oled.setTextSize(1);
    oled.setTextColor(SSD1306_WHITE);
    oled.setCursor(20, 0);
    oled.println("Connect the "+component);
    oled.setCursor(40, 0);
    oled.println("Then press OK");
    oled.display();
}*/




//this is for showing ics page by page
void icPages(int page, String pin_4[], int numIC)
{  
  int up_val = digitalRead(UP_PIN);
  int down_val = digitalRead(DOWN_PIN);

  int Start, End;
  //Serial.println(sizeof(pin_4));
  max_pages = ceil(numIC/6);
  //Serial.println("max pages: "+ String(max_pages));
  Start = page*6;
  //const int numIC = 20;

  if (numIC < Start+6){
    End = numIC;
  }
  else{
    End = Start+6;
  }

  oled.clearDisplay();         // clear display
  oled.setTextSize(1);         // text size
  oled.setCursor(0, 0);        // position to display

  for (int k=Start; k<End; k++){
    if (k == (Start + ic_sel)){
      ic_ind = k;
      oled.setTextColor(SSD1306_BLACK, SSD1306_WHITE);
      oled.println(pin_4[k]); 
    }
    else{
      oled.setTextColor(SSD1306_WHITE);
      oled.println(pin_4[k]);
    }
  }
  

  if (page != max_pages){
    oled.setTextColor(SSD1306_WHITE);
    oled.setCursor(104, 50);
    oled.println(">");
  }

  if (page != 0){
    oled.setTextColor(SSD1306_WHITE);
    oled.setCursor(0, 50);
    oled.println("<");
  }

  oled.display();

  if (up_val==0){
    if (ic_sel == 0){
      if (page == max_pages){
        ic_sel = numIC - 6*(max_pages) -1;
        Serial.println("ic_sel: "+ String(ic_sel));
      }
      else{
        ic_sel = 5;
      }
    }
    else{
      ic_sel = ic_sel - 1;
    }
    delay(100);
  }

  if (down_val==0){

    if (page == max_pages){
        if (max_pages*6 + ic_sel +1 == numIC){
          ic_sel = 0;
        }
        else{
          ic_sel = ic_sel + 1;
        }
    }

    else if (ic_sel == 5){
      ic_sel = 0;
    }
    
    else{
      ic_sel = ic_sel + 1;
    }
    delay(100);
  }
}

void backFoward()
{
  int right_val = digitalRead(RIGHT_PIN);
  int left_val = digitalRead(LEFT_PIN);

  if (right_val == 0){
    if (page != max_pages){
    page= page+1;
    ic_sel = 0;
    }
    delay(150);
  }

  if (left_val == 0){
    if (page != 0){
    page= page-1;
    ic_sel = 0;
    }    
    delay(150);
  }
}

//select the component and do testing
void compOK(){
  int ind = page*6 + ic_sel;
  //index_sel[1] = ind;
  //index_sel[0] = pin_number; //4,6,8,12,14

  oled.clearDisplay();         // clear display
  oled.setTextSize(1);         // text size
  oled.setCursor(20, 25);        // position to display
  oled.println("Testing.... ");
  oled.display();
  delay(100);

  //multi(index_sel[1]);
  
  if (tested_state == "not tested"){
    if (status_of_test != 0){
      oled.clearDisplay();        
      oled.setTextSize(1);         
      oled.setCursor(5,10);        
      oled.println("Out of " );
      oled.setCursor(25,20);
      oled.println(" test cases");
      oled.setCursor(35,30);
      oled.println("passed!!!");
      delay(500);
    }
    else{
      oled.clearDisplay();         // clear display
      oled.setTextSize(1);         // text size
      oled.setCursor(20, 15);
      oled.println("All test cases");
      oled.setCursor(35, 25);
      oled.println("passed!!!");
      delay(500);
    }
    tested_state = "tested";
  }
  
}

void homeorretest()
{
  int right_val = digitalRead(RIGHT_PIN);
  int left_val = digitalRead(LEFT_PIN);

  oled.setTextSize(1);
  
  oled.setTextColor(SSD1306_WHITE);
  oled.setCursor(0,50);
  oled.println("< Retest");
  oled.setCursor(90,50);
  oled.println("Home >");
  
  oled.display();

  

      if (right_val == 0){
        state = "home";
        tested_state = "not tested";
        state = "home";
        mode_selected = 0; 
        bjt_selected = 0;  
        return_home = 0;    
        page = 0; 
        ic_sel = 0; 
        pin_number = 0;
        retest_mode = "off";
      }
      else if (left_val == 0){
        tested_state = "not tested";
        retest_mode = "on";
      }
}