/*
   MicroDexed

   MicroDexed is a port of the Dexed sound engine
   (https://github.com/asb2m10/dexed) for the Teensy-3.5/3.6 with audio shield.
   Dexed ist heavily based on https://github.com/google/music-synthesizer-for-android

   (c)2018,2019 H. Wirtz <wirtz@parasitstudio.de>

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
*/

#ifdef ENABLE_LCD_UI
#ifndef _UI_HPP_
#define _UI_HPP_

#include "config.h"
#include "LiquidCrystalPlus_I2C.h"
#include <LCDMenuLib2.h>
#include <Encoder.h>

#define _LCDML_DISP_cols  LCD_cols
#define _LCDML_DISP_rows  LCD_rows

#define _LCDML_DISP_cfg_cursor                     0x7E   // cursor Symbol
#define _LCDML_DISP_cfg_scrollbar                  1      // enable a scrollbar

extern config_t configuration;
//void set_volume(float v, float p);
extern char bank_names[MAX_BANKS][BANK_NAME_LEN];
extern char bank_name[BANK_NAME_LEN];
extern char voice_name[VOICE_NAME_LEN];
extern char voice_names[MAX_VOICES][VOICE_NAME_LEN];
extern void strip_extension(char* s, char *target);
extern void eeprom_write(void);
extern bool get_voice_names_from_bank(uint8_t b);
extern bool load_sysex(uint8_t b, uint8_t v);
extern value_change_t soften_volume;
extern value_change_t soften_filter_res;
extern value_change_t soften_filter_cut;

/***********************************************************************
   GLOBAL
************************************************************************/
elapsedMillis back_from_volume;

LiquidCrystalPlus_I2C lcd(LCD_I2C_ADDRESS, _LCDML_DISP_cols, _LCDML_DISP_rows);

const uint8_t scroll_bar[5][8] = {
  {B10001, B10001, B10001, B10001, B10001, B10001, B10001, B10001}, // scrollbar top
  {B11111, B11111, B10001, B10001, B10001, B10001, B10001, B10001}, // scroll state 1
  {B10001, B10001, B11111, B11111, B10001, B10001, B10001, B10001}, // scroll state 2
  {B10001, B10001, B10001, B10001, B11111, B11111, B10001, B10001}, // scroll state 3
  {B10001, B10001, B10001, B10001, B10001, B10001, B11111, B11111}  // scrollbar bottom
};

enum { ENC_R, ENC_L };
enum { MENU_START, MENU_VOICE, MENU_EDIT, MENU_VOLUME };
enum {MENU_VOICE_BANK, MENU_VOICE_SOUND};
uint8_t menu_state = MENU_START;
uint8_t menu_voice = MENU_VOICE_SOUND;

void lcdml_menu_display(void);
void lcdml_voice_menu_display(void);
void lcdml_menu_clear(void);
void lcdml_menu_control(void);
void encoder_right_up(void);
void encoder_right_down(void);
void encoder_right_button_long(void);
void encoder_right_button_short(void);
void encoder_left_up(void);
void encoder_left_down(void);
void encoder_left_button_long(void);
void encoder_left_button_short(void);
void lcdml_voice_menu_control(void);
void UI_func_sound(uint8_t param);
void UI_func_reverb_roomsize(uint8_t param);
void UI_func_reverb_damping(uint8_t param);
void UI_func_reverb_level(uint8_t param);
void UI_func_chorus_frequency(uint8_t param);
void UI_func_chorus_depth(uint8_t param);
void UI_func_chorus_level(uint8_t param);
void UI_func_delay_time(uint8_t param);
void UI_func_delay_feedback(uint8_t param);
void UI_func_delay_level(uint8_t param);
void UI_func_filter_cutoff(uint8_t param);
void UI_func_filter_resonance(uint8_t param);
void UI_func_midi_channel(uint8_t param);
void UI_func_loudness(uint8_t param);
void UI_func_panorama(uint8_t param);
void UI_func_stereo_mono(uint8_t param);
void UI_func_polyphony(uint8_t param);
void UI_func_engine(uint8_t param);
void UI_func_information(uint8_t param);
void UI_func_voice_selection(uint8_t param);
void UI_func_volume(uint8_t param);
void UI_func_back(uint8_t param);
void UI_func_goToRootMenu(uint8_t param);

// normal menu
LCDMenuLib2_menu LCDML_0(255, 0, 0, NULL, NULL); // normal root menu element (do not change)
LCDMenuLib2 LCDML(LCDML_0, _LCDML_DISP_rows, _LCDML_DISP_cols, lcdml_menu_display, lcdml_menu_clear, lcdml_menu_control);

// LCDML_add(id, prev_layer, new_num, lang_char_array, callback_function)
LCDML_add(0, LCDML_0, 1, "Sound", UI_func_sound);
LCDML_add(1, LCDML_0, 2, "Effect", NULL);
LCDML_add(2, LCDML_0_2, 1, "Reverb", NULL);
LCDML_add(3, LCDML_0_2_1, 1, "Roomsize", UI_func_reverb_roomsize);
LCDML_add(4, LCDML_0_2_1, 2, "Damping", UI_func_reverb_damping);
LCDML_add(5, LCDML_0_2_1, 3, "Level", UI_func_reverb_level);
LCDML_add(6, LCDML_0_2, 2, "Chorus", NULL);
LCDML_add(7, LCDML_0_2_2, 1, "Frequency", UI_func_chorus_frequency);
LCDML_add(8, LCDML_0_2_2, 2, "Depth", UI_func_chorus_depth);
LCDML_add(9, LCDML_0_2_2, 3, "Level", UI_func_chorus_level);
LCDML_add(10, LCDML_0_2, 3, "Delay", NULL);
LCDML_add(11, LCDML_0_2_3, 1, "Time", UI_func_delay_time);
LCDML_add(12, LCDML_0_2_3, 2, "Feedback", UI_func_delay_feedback);
LCDML_add(13, LCDML_0_2_3, 3, "Level", UI_func_delay_level);
LCDML_add(14, LCDML_0_2, 4, "Filter", NULL);
LCDML_add(15, LCDML_0_2_4, 1, "Cutoff", UI_func_filter_cutoff);
LCDML_add(16, LCDML_0_2_4, 2, "Resonance", UI_func_filter_resonance);
LCDML_add(17, LCDML_0, 3, "Store", NULL);
LCDML_add(18, LCDML_0, 4, "System", NULL);
LCDML_add(19, LCDML_0_4, 1, "MIDI Channel", UI_func_midi_channel);
LCDML_add(20, LCDML_0_4, 2, "Loudness", UI_func_loudness);
LCDML_add(21, LCDML_0_4, 3, "Panorama", UI_func_panorama);
LCDML_add(22, LCDML_0_4, 4, "Stereo/Mono", UI_func_stereo_mono);
LCDML_add(23, LCDML_0_4, 5, "Polyphony", UI_func_polyphony);
LCDML_add(24, LCDML_0_4, 6, "Engine", UI_func_engine);
LCDML_add(25, LCDML_0, 5, "Info", UI_func_information);
#define _LCDML_DISP_cnt 25

// create menu
LCDML_createMenu(_LCDML_DISP_cnt);

/***********************************************************************
   CONTROL
 ***********************************************************************/
#define g_LCDML_CONTROL_button_long_press LONG_BUTTON_PRESS
#define g_LCDML_CONTROL_button_short_press BUT_DEBOUNCE_MS

//#define ENCODER_OPTIMIZE_INTERRUPTS //Only when using pin2/3 (or 20/21 on mega)
Encoder ENCODER[NUM_ENCODER] = {Encoder(ENC_R_PIN_B, ENC_R_PIN_A), Encoder(ENC_L_PIN_B, ENC_L_PIN_A)};

long  g_LCDML_CONTROL_button_press_time[NUM_ENCODER] = {0, 0};
bool  g_LCDML_CONTROL_button_prev[NUM_ENCODER] = {HIGH, HIGH};
uint8_t g_LCDML_CONTROL_prev[NUM_ENCODER] = {0, 0};

void lcdml_menu_control(void)
{
  // If something must init, put in in the setup condition
  if (LCDML.BT_setup())
  {
    pinMode(BUT_R_PIN, INPUT_PULLUP);
    pinMode(BUT_L_PIN, INPUT_PULLUP);
  }

  if (back_from_volume > BACK_FROM_VOLUME_MS && menu_state == MENU_VOLUME)
  {
    UI_func_voice_selection(0);
    return;
  }

  //Volatile Variable
  long g_LCDML_CONTROL_Encoder_position[NUM_ENCODER] = {ENCODER[ENC_R].read(), ENCODER[ENC_L].read()};
  bool button[NUM_ENCODER] = {digitalRead(BUT_R_PIN), digitalRead(BUT_L_PIN)};

  /************************************************************************************
    Basic encoder handlying (from LCDMenuLib2
   ************************************************************************************/
  // RIGHT
  if (g_LCDML_CONTROL_Encoder_position[ENC_R] <= -3)
  {
    if (!button[ENC_R])
    {
      LCDML.BT_left();
      g_LCDML_CONTROL_button_prev[ENC_R] = LOW;
      g_LCDML_CONTROL_button_press_time[ENC_R] = -1;
    }
    else
    {
      encoder_right_up();
    }
    ENCODER[ENC_R].write(g_LCDML_CONTROL_Encoder_position[ENC_R] + 4);
  }
  else if (g_LCDML_CONTROL_Encoder_position[ENC_R] >= 3)
  {

    if (!button[ENC_R])
    {
      LCDML.BT_right();
      g_LCDML_CONTROL_button_prev[ENC_R] = LOW;
      g_LCDML_CONTROL_button_press_time[ENC_R] = -1;
    }
    else
    {
      encoder_right_down();
    }
    ENCODER[ENC_R].write(g_LCDML_CONTROL_Encoder_position[ENC_R] - 4);
  }
  else
  {
    if (!button[ENC_R] && g_LCDML_CONTROL_button_prev[ENC_R]) //falling edge, button[ENC_R] pressed
    {
      g_LCDML_CONTROL_button_prev[ENC_R] = LOW;
      g_LCDML_CONTROL_button_press_time[ENC_R] = millis();
    }
    else if (button[ENC_R] && !g_LCDML_CONTROL_button_prev[ENC_R]) //rising edge, button[ENC_R] not active
    {
      g_LCDML_CONTROL_button_prev[ENC_R] = HIGH;

      if (g_LCDML_CONTROL_button_press_time[ENC_R] < 0)
      {
        g_LCDML_CONTROL_button_press_time[ENC_R] = millis();
        //Reset for left right action
      }
      else if ((millis() - g_LCDML_CONTROL_button_press_time[ENC_R]) >= g_LCDML_CONTROL_button_long_press)
      {
        LCDML.BT_quit();
        if (menu_state == MENU_EDIT)
        {
          LCDML.BT_quit();
        }
        else if (menu_state == MENU_VOICE)
        {
          encoder_right_button_long();
        }
      }
      else if ((millis() - g_LCDML_CONTROL_button_press_time[ENC_R]) >= g_LCDML_CONTROL_button_short_press)
      {
        encoder_right_button_short();
      }
    }
  }
  // LEFT
  if (g_LCDML_CONTROL_Encoder_position[ENC_L] <= -3)
  {
    if (!button[ENC_L])
    {
      //LCDML.BT_left();
      g_LCDML_CONTROL_button_prev[ENC_L] = LOW;
      g_LCDML_CONTROL_button_press_time[ENC_L] = -1;
    }
    else
    {
      encoder_left_up();
    }
    ENCODER[ENC_L].write(g_LCDML_CONTROL_Encoder_position[ENC_L] + 4);
  }
  else if (g_LCDML_CONTROL_Encoder_position[ENC_L] >= 3)
  {

    if (!button[ENC_L])
    {
      //LCDML.BT_right();
      g_LCDML_CONTROL_button_prev[ENC_L] = LOW;
      g_LCDML_CONTROL_button_press_time[ENC_L] = -1;
    }
    else
    {
      encoder_left_down();
    }
    ENCODER[ENC_L].write(g_LCDML_CONTROL_Encoder_position[ENC_L] - 4);
  }
  else
  {
    if (!button[ENC_L] && g_LCDML_CONTROL_button_prev[ENC_L]) //falling edge, button[ENC_L] pressed
    {
      g_LCDML_CONTROL_button_prev[ENC_L] = LOW;
      g_LCDML_CONTROL_button_press_time[ENC_L] = millis();
    }
    else if (button[ENC_L] && !g_LCDML_CONTROL_button_prev[ENC_L]) //rising edge, button[ENC_L] not active
    {
      g_LCDML_CONTROL_button_prev[ENC_L] = HIGH;

      if (g_LCDML_CONTROL_button_press_time[ENC_L] < 0)
      {
        g_LCDML_CONTROL_button_press_time[ENC_L] = millis();
        //Reset for left right action
      }
      else if ((millis() - g_LCDML_CONTROL_button_press_time[ENC_L]) >= g_LCDML_CONTROL_button_long_press)
      {
        //LCDML.BT_quit();
        encoder_left_button_long();
      }
      else if ((millis() - g_LCDML_CONTROL_button_press_time[ENC_L]) >= g_LCDML_CONTROL_button_short_press)
      {
        //LCDML.BT_enter();
        encoder_left_button_short();
      }
    }
  }
}

/************************************************************************************
  RIGHT Encoder functions
 ************************************************************************************/
void encoder_right_up(void)
{
  switch (menu_state)
  {
    case MENU_EDIT:
    case MENU_VOLUME:
      menu_state = MENU_EDIT;
      LCDML.BT_down();
      break;
    case MENU_VOICE:
#ifdef DEBUG
      Serial.println(F("State: MENU_VOICE, Encoder left up"));
#endif
      switch (menu_voice)
      {
        case MENU_VOICE_BANK:
          if (configuration.bank < MAX_BANKS)
          {
            configuration.bank++;
            load_sysex(configuration.bank, configuration.voice);
            get_voice_names_from_bank(configuration.bank);
          }
          break;
        case MENU_VOICE_SOUND:
          if (configuration.voice < MAX_VOICES-1)
            configuration.voice++;
          else
          {
            if (configuration.bank < MAX_BANKS)
            {
              configuration.bank++;
              configuration.voice = 0;
            }
          }
          load_sysex(configuration.bank, configuration.voice);
          get_voice_names_from_bank(configuration.bank);
          eeprom_write();
      }
      UI_func_voice_selection(0);
      break;
  }
}

void encoder_right_down(void)
{
  switch (menu_state)
  {
    case MENU_EDIT:
    case MENU_VOLUME:
      menu_state = MENU_EDIT;
      LCDML.BT_up();
      break;
    case MENU_VOICE:
#ifdef DEBUG
      Serial.println(F("State: MENU_VOICE, Encoder left down"));
#endif
      switch (menu_voice)
      {
        case MENU_VOICE_BANK:
          if (configuration.bank > 0)
          {
            configuration.bank--;
            load_sysex(configuration.bank, configuration.voice);
            get_voice_names_from_bank(configuration.bank);
          }
          break;
        case MENU_VOICE_SOUND:
          if (configuration.voice > 0)
            configuration.voice--;
          else
          {
            if (configuration.bank > 0)
            {
              configuration.bank--;
              configuration.voice = 31;
            }
          }
          load_sysex(configuration.bank, configuration.voice);
          get_voice_names_from_bank(configuration.bank);
          eeprom_write();
      }
      UI_func_voice_selection(0);
      break;
  }
}

void encoder_right_button_long(void)
{
#ifdef DEBUG
  Serial.println(F("State: MENU_VOICE, button long press"));
#else
  ;
#endif
}

void encoder_right_button_short(void)
{
#ifdef DEBUG
  Serial.println(F("Encoder right short press"));
#endif
  if (menu_state == MENU_EDIT)
  {
    LCDML.BT_enter();
  }
  else if (menu_state == MENU_VOICE)
  {
#ifdef DEBUG
    Serial.println(F("State: MENU_VOICE, button short press"));
#endif
    if (menu_voice == MENU_VOICE_BANK)
      menu_voice = MENU_VOICE_SOUND;
    else
      menu_voice = MENU_VOICE_BANK;
    UI_func_voice_selection(0);
  }
}

/************************************************************************************
  LEFT Encoder functions
 ************************************************************************************/
void encoder_left_up(void)
{
#ifdef DEBUG
  Serial.println(F("Volume +"));
#endif
  if (configuration.vol < 0.96)
  {
    soften_volume.diff =  0.05 / SOFTEN_VALUE_CHANGE_STEPS;
    soften_volume.steps = SOFTEN_VALUE_CHANGE_STEPS;
    eeprom_write();
  }
  UI_func_volume(0);
}

void encoder_left_down(void)
{
#ifdef DEBUG
  Serial.println(F("Volume -"));
#endif
  if (configuration.vol > 0.04)
  {
    soften_volume.diff =  -0.05 / SOFTEN_VALUE_CHANGE_STEPS;
    soften_volume.steps = SOFTEN_VALUE_CHANGE_STEPS;
    eeprom_write();
  }
  UI_func_volume(0);
}

void encoder_left_button_long(void)
{
#ifdef DEBUG
  Serial.println(F("Encoder left long press"));
#else
  ;
#endif
}

void encoder_left_button_short(void)
{
#ifdef DEBUG
  Serial.println(F("Encoder left short press"));
#endif
  if (menu_state == MENU_EDIT)
  {
    menu_state = MENU_VOICE;
    UI_func_voice_selection(0);
  }
  else if (menu_state == MENU_VOICE)
  {
    menu_state = MENU_EDIT;
    LCDML.MENU_goRoot();
  }
}

/***********************************************************************
   DISPLAY
 ***********************************************************************/
void lcdml_menu_clear(void)
{
  lcd.clear();
  lcd.setCursor(0, 0);
}

void lcdml_menu_display(void)
{
  // update content
  // ***************
  if (LCDML.DISP_checkMenuUpdate()) {
    // clear menu
    // ***************
    LCDML.DISP_clear();

    // declaration of some variables
    // ***************
    // content variable
    char content_text[_LCDML_DISP_cols];  // save the content text of every menu element
    // menu element object
    LCDMenuLib2_menu *tmp;
    // some limit values
    uint8_t i = LCDML.MENU_getScroll();
    uint8_t maxi = _LCDML_DISP_rows + i;
    uint8_t n = 0;

    // check if this element has children
    if ((tmp = LCDML.MENU_getDisplayedObj()) != NULL)
    {
      // loop to display lines
      do
      {
        // check if a menu element has a condition and if the condition be true
        if (tmp->checkCondition())
        {
          // check the type off a menu element
          if (tmp->checkType_menu() == true)
          {
            // display normal content
            LCDML_getContent(content_text, tmp->getID());
            lcd.setCursor(1, n);
            lcd.print(content_text);
          }
          else
          {
            if (tmp->checkType_dynParam()) {
              tmp->callback(n);
            }
          }
          // increment some values
          i++;
          n++;
        }
        // try to go to the next sibling and check the number of displayed rows
      } while (((tmp = tmp->getSibling(1)) != NULL) && (i < maxi));
    }
  }

  if (LCDML.DISP_checkMenuCursorUpdate())
  {
    // init vars
    uint8_t n_max             = (LCDML.MENU_getChilds() >= _LCDML_DISP_rows) ? _LCDML_DISP_rows : (LCDML.MENU_getChilds());
    uint8_t scrollbar_min     = 0;
    uint8_t scrollbar_max     = LCDML.MENU_getChilds();
    uint8_t scrollbar_cur_pos = LCDML.MENU_getCursorPosAbs();
    uint8_t scroll_pos        = ((1.*n_max * _LCDML_DISP_rows) / (scrollbar_max - 1) * scrollbar_cur_pos);

    // display rows
    for (uint8_t n = 0; n < n_max; n++)
    {
      //set cursor
      lcd.setCursor(0, n);

      //set cursor char
      if (n == LCDML.MENU_getCursorPos()) {
        lcd.write(_LCDML_DISP_cfg_cursor);
      } else {
        lcd.write(' ');
      }

      // delete or reset scrollbar
      if (_LCDML_DISP_cfg_scrollbar == 1) {
        if (scrollbar_max > n_max) {
          lcd.setCursor((_LCDML_DISP_cols - 1), n);
          lcd.write((uint8_t)0);
        }
        else {
          lcd.setCursor((_LCDML_DISP_cols - 1), n);
          lcd.print(' ');
        }
      }
    }

    // display scrollbar
    if (_LCDML_DISP_cfg_scrollbar == 1) {
      if (scrollbar_max > n_max) {
        //set scroll position
        if (scrollbar_cur_pos == scrollbar_min) {
          // min pos
          lcd.setCursor((_LCDML_DISP_cols - 1), 0);
          lcd.write((uint8_t)1);
        } else if (scrollbar_cur_pos == (scrollbar_max - 1)) {
          // max pos
          lcd.setCursor((_LCDML_DISP_cols - 1), (n_max - 1));
          lcd.write((uint8_t)4);
        } else {
          // between
          lcd.setCursor((_LCDML_DISP_cols - 1), scroll_pos / n_max);
          lcd.write((uint8_t)(scroll_pos % n_max) + 1);
        }
      }
    }
  }
}

/***********************************************************************
   MENU
 ***********************************************************************/
void UI_func_sound(uint8_t param)
{
  if (LCDML.FUNC_setup())         // ****** SETUP *********
  {
    // setup function
    lcd.setCursor(0, 0);
    lcd.print(F("Filter Res."));
    lcd.setCursor(0, 1);
    lcd.print(F("<value>"));
  }

  if (LCDML.FUNC_loop())          // ****** LOOP *********
  {
    if (LCDML.BT_checkEnter()) { // check if any button is pressed (enter, up, down, left, right)
      // LCDML_goToMenu stops a running menu function and goes to the menu
      LCDML.FUNC_goBackToMenu();
    }
  }

  if (LCDML.FUNC_close())     // ****** STABLE END *********
  {
    // you can here reset some global vars or do nothing
  }
}

void UI_func_reverb_roomsize(uint8_t param)
{
  ;
}

void UI_func_reverb_damping(uint8_t param)
{
  ;
}

void UI_func_reverb_level(uint8_t param)
{
  ;
}

void UI_func_chorus_frequency(uint8_t param)
{
  ;
}

void UI_func_chorus_depth(uint8_t param)
{
  ;
}

void UI_func_chorus_level(uint8_t param)
{
  ;
}

void UI_func_delay_time(uint8_t param)
{
  ;
}

void UI_func_delay_feedback(uint8_t param)
{
  ;
}

void UI_func_delay_level(uint8_t param)
{
  ;
}

void UI_func_filter_cutoff(uint8_t param)
{
  ;
}

void UI_func_filter_resonance(uint8_t param)
{
  ;
}

void UI_func_midi_channel(uint8_t param)
{
  ;
}

void UI_func_loudness(uint8_t param)
{
  ;
}

void UI_func_panorama(uint8_t param)
{
  ;
}

void UI_func_stereo_mono(uint8_t param)
{
  ;
}

void UI_func_polyphony(uint8_t param)
{
  ;
}

void UI_func_engine(uint8_t param)
{
  ;
}

void UI_func_information(uint8_t param)
{
  if (LCDML.FUNC_setup())         // ****** SETUP *********
  {
    // setup function
    lcd.setCursor(0, 0);
    lcd.print(F("MicroDexed"));
    lcd.setCursor(0, 1);
    lcd.print(VERSION);
  }

  if (LCDML.FUNC_loop())          // ****** LOOP *********
  {
    // loop function, can be run in a loop when LCDML_DISP_triggerMenu(xx) is set
    // the quit button works in every DISP function without any checks; it starts the loop_end function
    if (LCDML.BT_checkEnter()) { // check if any button is pressed (enter, up, down, left, right)
      // LCDML_goToMenu stops a running menu function and goes to the menu
      LCDML.FUNC_goBackToMenu();
    }
  }

  if (LCDML.FUNC_close())     // ****** STABLE END *********
  {
    // you can here reset some global vars or do nothing
  }
}

void UI_func_voice_selection(uint8_t param)
{
#ifdef DEBUG
  Serial.println(F("UI_func_voice_selection()"));
#endif

  menu_state = MENU_VOICE;

  strip_extension(bank_names[configuration.bank], bank_name);

  //LCDML.DISP_clear();

  // display bank and voice number
  lcd.show(0, 0, 2, configuration.bank);
  lcd.show(1, 0, 2, configuration.voice + 1);

  // display names
  lcd.show(0, 4, 10, bank_name);
  lcd.show(1, 4, 10, voice_names[configuration.voice]);

  // display selections
  switch (menu_voice)
  {
    case MENU_VOICE_BANK:
      lcd.show(0, 2, 2, " [");
      lcd.show(0, 14, 2, "] ");
      lcd.show(1, 2, 2, "  ");
      lcd.show(1, 14, 2, "  ");
      break;
    case MENU_VOICE_SOUND:
      lcd.show(0, 2, 2, "  ");
      lcd.show(0, 14, 2, "  ");
      lcd.show(1, 2, 2, " [");
      lcd.show(1, 14, 2, "] ");
      break;
  }
}

void UI_func_volume(uint8_t param)
{
#ifdef DEBUG
  Serial.println(F("UI_func_volume()"));
#endif

  menu_state = MENU_VOLUME;
  back_from_volume = 0;

  // update LCD content
  LCDML.DISP_clear();
  lcd.show(0, 0, 8, "Volume: ");
  lcd.show(0, 9, 3, configuration.vol * 100.0 + 0.5);
  lcd.setCursor(1, 1);
  for (uint8_t i = 0; i < LCD_cols; i++)
  {
    if (i < int((LCD_cols - 2) * configuration.vol + 0.5))
      lcd.print("*");
    else
      lcd.print(" ");
  }
  lcd.show(1, 0, 1, "[");
  lcd.show(1, 15, 1, "]");
}
#endif
#endif