#include <TinyWireM.h> // To use the Adafruit's TinyWireM library:
#include <Tiny4kOLED.h> // we are using the Tiny4kOLED library to draw on the display

#define BUTTON_UP_PIN PB4 // pin for UP button 
#define BUTTON_DOWN_PIN PB3 // pin for DOWN button
#define BUTTON_ENTER_PIN PB5 // pin for ENTER button

#include "fontpixelop16b.h" // font pixel operator bold 
#include "fontpixelop16.h" // font pixel operator regular
#include "bg.h" // 128x64px fullscreen background image
//#include "icons.h" // 16x16px icons


const unsigned char scrollbar_empty [] PROGMEM =  { B00000000, B01010101, B00000000  }; // image for scrollbar background 3x8px
const unsigned char scrollbar_filled [] PROGMEM = { B11111110, B11111111, B11111110  }; // image for scrollbar handle 3x8px


const int NUM_ITEMS = 7; // number of items in the list 
const int MAX_ITEM_LENGTH = 6; // maximum characters for the item name

char menu_items [NUM_ITEMS] [MAX_ITEM_LENGTH] = {  // array with item names
  { "HP" }, // menu item = 0
  { "DEF" }, // menu item = 1
  { "ACC" }, // menu item = 2 
  { "DEX" }, // menu item = 3
  { "MOV" }, // menu item = 4
  { "ATK" }, // menu item = 5 
  { "DAM" }, // menu item = 6
 };

int current_screen = 0;   // 0 = menu, 1 = Stat value,

int button_ENTER_clicked = 0; // only perform action when button is clicked, and wait until another press


int8_t HP_stat = 20; // initial value for the HP stat
int8_t DEF_stat = 20; // initial value for the DEF stat
int8_t ACC_stat = 20; // initial value for the ACC stat
int8_t DEX_stat = 20; // initial value for the DEX stat
int8_t MOV_stat = 2; // initial value for the MOV stat
int8_t ATK_stat = 20; // initial value for the ATK stat
int8_t DAM_stat = 2; // initial value for the DAM stat


const int NUM_OF_STATS = 7;   //8; // number of items in the list 
const int MAX_STAT_LENGTH = 20; // maximum characters for the item name

int8_t stat_value[NUM_OF_STATS][MAX_STAT_LENGTH] = { HP_stat, DEF_stat, ACC_stat, DEX_stat, MOV_stat, ATK_stat, DAM_stat};

int item_selected = 0; // which item in the menu is selected
int item_sel_previous; // previous item - used in the menu screen to draw the item before the selected one
int item_sel_next; // next item - used in the menu screen to draw next item after the selected one


void setup() {

  pinMode(BUTTON_UP_PIN, INPUT_PULLUP); // up button, set to INPUT_PULLUP = when not pressed, pin is HIGH
  pinMode(BUTTON_DOWN_PIN, INPUT_PULLUP); // down button, set to INPUT_PULLUP = when not pressed, pin is HIGH
  pinMode(BUTTON_ENTER_PIN, INPUT_PULLUP); // enter button, set to INPUT_PULLUP = when not pressed, pin is HIGH
  
  oled.begin(64, 48, sizeof(tiny4koled_init_64x48), tiny4koled_init_64x48); // display initialization
  
  oled.enableChargePump(); // The default is off, but most boards need this.
  oled.setRotation(1);     // The default orientation is not the most commonly used.
  oled.clear();  // clear the screen

  
  oled.on(); // turn on the display
  screen_refresh();
}

int stat_display_value (int value) {
  if(value == 0) {
       return HP_stat;
      }
      if(value == 1) {
        return DEF_stat;
      }  
      if(value == 2) {
        return ACC_stat;
      }  
      if(value == 3) {
        return DEX_stat;
      }  
      if(value == 4) {
       return MOV_stat;
      }  
      if(value == 5) {
        return ATK_stat;
      }  
      if(value == 6) {
        return DAM_stat;
      }  
}

void fill_rest_of_line() {
  int stored_cursor_x = oled.getCursorX(); // get cursor X position in pixels
  int stored_cursor_y = oled.getCursorY(); // get cursor Y position in pages
  int clear_width = 32 - stored_cursor_x;//54 - stored_cursor_x; // calculate how much pixels we need to fill (old value at 110)
  oled.fillLength(/*B10101010*/ 0, clear_width); // fill specified number of columns with black color
  oled.setCursor(stored_cursor_x, stored_cursor_y + 1); // jump to the next page
  oled.fillLength(/*B10101010*/ 0, clear_width); // fill specified number of columns with black color
}

void fill_rest_of_value_line() {
  int value_stored_cursor_x = oled.getCursorX(); // get cursor X position in pixels
  int value_stored_cursor_y = oled.getCursorY(); // get cursor Y position in pages
  int value_clear_width = 58 - value_stored_cursor_x;//54 - stored_cursor_x; // calculate how much pixels we need to fill (old value at 110)
  oled.fillLength(/*B10101010*/ 0, value_clear_width); // fill specified number of columns with black color
  oled.setCursor(value_stored_cursor_x, value_stored_cursor_y + 1); // jump to the next page
  oled.fillLength(/*B10101010*/ 0, value_clear_width); // fill specified number of columns with black color
}


void screen_refresh() {
  if(current_screen == 0){
    oled.bitmap(0,1,64,6,epd_bitmap_BG_3);
  }
  if(current_screen == 1){
    oled.bitmap(0,1,64,6,epd_bitmap_BG_4);
  }
  // set correct values for the previous and next items
  item_sel_previous = item_selected - 1;
  if (item_sel_previous < 0) {item_sel_previous = NUM_ITEMS - 1;} // previous item would be below first = make it the last
  item_sel_next = item_selected + 1;  
  if (item_sel_next >= NUM_ITEMS) {item_sel_next = 0;} // next item would be after last = make it the first  

    // draw top item
  oled.setFont(FONTPIXELOP16); // regular font
  oled.setCursor(6,0);     //(22, 0); // set cursor, X is in pixels, Y is in pages
  oled.print(menu_items[item_sel_previous]); // draw menu item label
  fill_rest_of_line();
  oled.setCursor(42, 0); // set cursor, X is in pixels, Y is in pages
  oled.print(stat_display_value(item_sel_previous));
  fill_rest_of_value_line();
  //oled.bitmap(4, 0, 4+16, 2, bitmap_icons[item_sel_previous]); // draw icons
  

    // draw middle item
  oled.setFont(FONTPIXELOP16); // regular font
  oled.setCursor(6,3);      //(22, 3); // set cursor, X is in pixels, Y is in pages
  oled.print(menu_items[item_selected]); // draw menu item label 
  fill_rest_of_line(); // fill rest of the line with black color
  oled.setCursor(42, 3); // set cursor, X is in pixels, Y is in pages
  oled.print(stat_display_value(item_selected));
  fill_rest_of_value_line();
  //oled.bitmap(4, 3, 4+16, 5, bitmap_icons[item_selected]); // draw icons  

    // draw bottom item
  oled.setFont(FONTPIXELOP16);  // regular font
  oled.setCursor(6,6);   //(22, 6); // set cursor, X is in pixels, Y is in pages
  oled.print(menu_items[item_sel_next]); // draw menu item label   
  fill_rest_of_line(); // fill rest of the line with black color
  oled.setCursor(42, 6); // set cursor, X is in pixels, Y is in pages
  oled.print(stat_display_value(item_sel_next));
  fill_rest_of_value_line();
  //oled.bitmap(4, 6, 4+16, 8, bitmap_icons[item_sel_next]); // draw icons 

    // draw scrollbar
  for (byte i=0; i<7; i++) { // for all 8 pages (byte i=0; i<8; i++)
    if (i == item_selected) {
      oled.bitmap(61, i, 61+3, i+1, scrollbar_filled); // draw scrollbar handle = scrollbar_filled 
    } else { 
      oled.bitmap(61, i, 61+3, i+1, scrollbar_empty); // draw scrollbar background = scrollbar_empty  
    }
  }

}


void loop() { // main loop


  if ((digitalRead(BUTTON_ENTER_PIN) == LOW) && (button_ENTER_clicked == 0)) { // select button clicked, jump between screens
    button_ENTER_clicked = 1; // set button to clicked to only perform the action once
    if (current_screen == 0) {current_screen = 1;} // menu screen --> stat screen
    else {current_screen = 0;} // stat screen --> menu screen
    screen_refresh();
    
  }
  if ((digitalRead(BUTTON_ENTER_PIN) == HIGH) && (button_ENTER_clicked == 1)) { // unclick 
    button_ENTER_clicked = 0;
  } 

  
  if(current_screen==0){
    if (digitalRead(BUTTON_UP_PIN) == LOW) { // button UP is pressed
      item_selected = (item_selected - 1 + NUM_ITEMS) % NUM_ITEMS; // switch to the previous item
    screen_refresh();
    }

    if (digitalRead(BUTTON_DOWN_PIN) == LOW) { // button DOWN is pressed
      item_selected = (item_selected + 1) % NUM_ITEMS; // switch to the next item
    screen_refresh();
    }

  }


  if(current_screen==1){

    if (digitalRead(BUTTON_UP_PIN) == LOW) { // button UP is pressed
      if(item_selected == 0 && HP_stat < 20) {
        HP_stat = HP_stat + 1;
      }
      if(item_selected == 1 && DEF_stat < 20) {
        DEF_stat = DEF_stat + 1;
      }  
      if(item_selected == 2 && ACC_stat < 20) {
        ACC_stat = ACC_stat + 1;
      }  
      if(item_selected == 3 && DEX_stat < 20) {
        DEX_stat = DEX_stat + 1;
      }  
      if(item_selected == 4 && MOV_stat < 20) {
        MOV_stat = MOV_stat + 1;
      }  
      if(item_selected == 5 && ATK_stat < 20) {
        ATK_stat = ATK_stat + 1;
      }  
      if(item_selected == 6 && DAM_stat < 20) {
        DAM_stat = DAM_stat + 1;
      }  
      
      screen_refresh();
    }

    if (digitalRead(BUTTON_DOWN_PIN) == LOW) { // button DOWN is pressed
      if(item_selected == 0 && HP_stat > 0) {
        HP_stat = HP_stat - 1;
      }
      if(item_selected == 1 && DEF_stat > 0) {
        DEF_stat = DEF_stat - 1;
      }  
      if(item_selected == 2 && ACC_stat > 0) {
        ACC_stat = ACC_stat - 1;
      }  
      if(item_selected == 3 && DEX_stat > 0) {
        DEX_stat = DEX_stat - 1;
      }  
      if(item_selected == 4 && MOV_stat > 0) {
        MOV_stat = MOV_stat - 1;
      }  
      if(item_selected == 5 && ATK_stat > 0) {
        ATK_stat = ATK_stat - 1;
      }  
      if(item_selected == 6 && DAM_stat > 0) {
        DAM_stat = DAM_stat - 1;
      }  
      
      screen_refresh();
    }
  }

}