#include <U8g2lib.h>
#include "AiEsp32RotaryEncoder.h"
#include <Preferences.h>
#include "html.h"

//display
U8X8_SSD1306_128X64_NONAME_HW_I2C display;
//rotary encoder
#define ROTARY_ENCODER_A_PIN 19
#define ROTARY_ENCODER_B_PIN 18
#define ROTARY_ENCODER_BUTTON_PIN 23
#define ROTARY_ENCODER_STEPS 4

AiEsp32RotaryEncoder rotaryEncoder = AiEsp32RotaryEncoder(ROTARY_ENCODER_A_PIN, ROTARY_ENCODER_B_PIN, ROTARY_ENCODER_BUTTON_PIN, -1, ROTARY_ENCODER_STEPS);
int selectedItem = 0;
int tempSelectedItem = 0;
bool menuDisplayed = false;
int MAX_DISPLAYED = 6;
int MAX_ITEMS = 10;

Preferences preferences;

struct menuItem {
   String name;
   String value;
};

menuItem items[12];
int itemsCount = 0;

void IRAM_ATTR readEncoderISR()
{
    rotaryEncoder.readEncoder_ISR();
}

void savePrefs() {
  preferences.putString("ssid", "my_ssid");
  preferences.putString("pwd", "my_password");
  preferences.putString("s1n", "Item 1");
  preferences.putString("s1u", "Item 1 value");
  preferences.putString("s2n", "Item 2");
  preferences.putString("s2u", "Item 2 value");
  preferences.putString("s3n", "Item 3");
  preferences.putString("s3u", "Item 3 value");
  preferences.putString("s4n", "Item 4");
  preferences.putString("s4u", "Item 4 value");
  preferences.putString("s5n", "Item 5");
  preferences.putString("s5u", "Item 5 value");
  preferences.putString("s6n", "Item 6");
  preferences.putString("s6u", "Item 6 value");
  preferences.putString("s7n", "Item 7");
  preferences.putString("s7u", "Item 7 value");
  preferences.putString("s8n", "Item 8");
  preferences.putString("s8u", "Item 8 value");
}

void readPrefs() {
  char key[10]; 
  itemsCount = 0;
  for(int i=1; i <= MAX_ITEMS; i++) {// we can have maximum 10 items
    strcpy(key, "s");
    char numberString[4];
    itoa(i, numberString, 10); 
    strcat(key, numberString);
    strcat(key, "n");
    String itemName = preferences.getString(key, "");
    key[0] = '\0';
    strcpy(key, "s");
    strcat(key, numberString);
    strcat(key, "u");
    String itemValue = preferences.getString(key, "");
    key[0] = '\0';
    if (itemName != "") {
      while (itemName.length() < 16) {
            itemName += " "; // Append a space
        }
      items[itemsCount] = {itemName, itemValue};
      itemsCount++;
    }
  }
  //add empty space and "Setup Mode"
  items[itemsCount] = {"                ", ""};
  itemsCount++;
  items[itemsCount] = {"Setup Mode      ", ""};
  itemsCount++;
}

String getAccessHTML() {
  String html;
  preferences.begin("my-prefs", false);
  String ssid = preferences.getString("ssid", ""); 
  String password = preferences.getString("pwd", "");
  html = String(ACCESS_page_start);
  html += "<tr><td>SSID:</td><td><input type='text' name='ssid' value='" + ssid + "'></td></tr>";
  html += "<tr><td>Password:</td><td><input type='password' name='password' value='" + password + "'></td></tr>";
  html += String(ACCESS_page_end);
  preferences.end();
  return html;
}

String getItemsHTML() {
  char key[10]; 
  String html;
  preferences.begin("my-prefs", false);
  html = String(ITEMS_page_start);
  for(int i=1; i <= MAX_ITEMS; i++) {
    strcpy(key, "s");
    char numberString[4];
    itoa(i, numberString, 10); 
    strcat(key, numberString);
    strcat(key, "n");
    String itemName = preferences.getString(key, "");
    key[0] = '\0';
    strcpy(key, "s");
    strcat(key, numberString);
    strcat(key, "u");
    String itemValue = preferences.getString(key, "");
    key[0] = '\0';
    html += "<tr><td style='width:88px'>";
    html += i;
    html += "</td><td style='width:162px'><input type='text' name='s";
    html += i;
    html += "n' maxlength='16' value='";
    html += itemName;
    html += "'></td><td style='width:232px'><input type='text' name='s";
    html += i;
    html += "u' size='40' value='";
    html += itemValue;
    html += "'></td></tr>";
  }
  html += String(ITEMS_page_end);
  preferences.end();
  return html;
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  preferences.begin("my-prefs", false);
  savePrefs();
  String ssid = preferences.getString("ssid", ""); // The second parameter is a default value
  String password = preferences.getString("pwd", "");
  readPrefs();
  preferences.end();
  delay(250); // wait for the OLED to power up
  display.begin();
  display.setFont(u8x8_font_chroma48medium8_r);
  display.draw1x2String(0,0,"ESP32 Meniu!");

  rotaryEncoder.begin();
  rotaryEncoder.setup(readEncoderISR);
  rotaryEncoder.setBoundaries(0, 100, false); //minValue, maxValue, circleValues true|false (when max go to min and vice versa)
  rotaryEncoder.setEncoderValue(25);
  rotaryEncoder.setAcceleration(50);
  Serial.println("--------");
  Serial.println(getItemsHTML());
  Serial.println("--------");
  int tries = 0;
  Serial.println("Trying to connect.. ");
  while (true) {
    tries++;
    Serial.print("try: ");
    Serial.print(tries);
    Serial.println("...");
    delay(1500);
  }
}

int getStart() {
  if (itemsCount > MAX_DISPLAYED) {
    if (tempSelectedItem >= MAX_DISPLAYED) {
      return tempSelectedItem - MAX_DISPLAYED + 1;
    }
    return 0; 
  } else {
    return 0;
  }
}

void displayItems() {
  int start = getStart();
  int j = 2;
  for (int i = start; i <= start + MAX_DISPLAYED - 1; i++) {
    if (i == tempSelectedItem) {
      display.setInverseFont(1);
    } 
    display.drawString(0, j++, items[i].name.c_str());
    display.setInverseFont(0);
  }
}

void displayMenu() {
  rotaryEncoder.setBoundaries(0, itemsCount - 1, false); //minValue, maxValue, circleValues true|false (when max go to min and vice versa)
  rotaryEncoder.setEncoderValue(tempSelectedItem);
  rotaryEncoder.disableAcceleration();
  menuDisplayed = true;
  display.clearDisplay();
  display.drawString(0, 0, "Select item");
  tempSelectedItem = selectedItem;
  displayItems();
}

void hideMenu() {
  //do not select last 2 items
  if (tempSelectedItem == itemsCount - 1) {
    return;
  }
  if (tempSelectedItem == itemsCount - 2) {
    return;
  }
  menuDisplayed = false;
  selectedItem = tempSelectedItem;
  display.clearDisplay();
  display.draw1x2String(0, 0, "ESP32 Meniu!");
  rotaryEncoder.setBoundaries(0, 100, false); //minValue, maxValue, circleValues true|false (when max go to min and vice versa)
  rotaryEncoder.setEncoderValue(25);
  rotaryEncoder.setAcceleration(50);
}

void loop() {
  // put your main code here, to run repeatedly:
  delay(10); // this speeds up the simulation
  if (rotaryEncoder.isEncoderButtonClicked())
    {
      if (menuDisplayed) {
          hideMenu();
      } else {
          displayMenu();
      }
    }
    if (rotaryEncoder.encoderChanged())
    {
      if (menuDisplayed) {
        tempSelectedItem = rotaryEncoder.readEncoder();
        displayItems();
      }
    }
}