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

// add line numbers for following two comments

/*
 SCREEN_WIDTH
 SCREEN_HEIGHT
 display
 cursorX
 cursorY
 charWidth
 charHeight
 folderIcon
 fileIcon
 selectedIndex
 path
 files
 customPrint
 customPrintln
 basename
 listContents
 goBackInPath
 JOYSTICK_X_PIN
 JOYSTICK_Y_PIN
 JOYSTICK_BUTTON_PIN
 vec
 types
 setup
 yPlusPressed
 xPlusPressed
 xMinusPressed
 yMinusPressed
 lastClicked
 firstTime
 lastPath
 currentPath
 visibleStartIndex
 MAX_VISIBLE_LINES
 results
 resultTypes
*/

/*
 utils.cpp
  1
  2
 menu.cpp
  1
  2
  3
  4
  5
 controls.cpp
  1
  2
  3
*/


// start1 utils.cpp
// OLED display settings
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

// Cursor position tracking
int cursorX = 0;
int cursorY = 0;

// Constants for screen layout
const int charWidth = 6;  // Adjust based on font size
const int charHeight = 8; // Adjust based on font size
// end1 utils.cpp


// start1 menu.cpp
const unsigned char folderIcon [] PROGMEM = {
	0x00, 0xf0, 0x9c, 0x84, 0x84, 0xfc, 0x00, 0x00
};

// File icon (8x8 pixels)
const unsigned char fileIcon [] PROGMEM = {
	0x78, 0x94, 0x8c, 0x84, 0xb4, 0xb4, 0x84, 0x78
};


int selectedIndex = 0;
String path = "/";
String files =
  "d Folder 1\n"
  " f file 11\n"
  " f file 21\n"
  " d Folder 11\n"
  "  f file 12\n"
  "d Folder 2\n"
  " f file 13\n"
  "d Folder 3\n"
  "d Folder 4\n"
  "d Folder 5\n"
  "d Folder 6\n"
  "d Folder 7\n"
  "d Folder 8\n"
  "d Folder 9";
// end1 menu.cpp

// start2 utils.cpp

void customPrint(const char* text, bool invert) {
  int textWidth = strlen(text) * charWidth;

  if (invert) {
    // Draw inversion background for the text
    display.fillRect(cursorX, cursorY, textWidth, charHeight, SSD1306_WHITE);
    display.setTextColor(SSD1306_BLACK, SSD1306_WHITE); // Inverted text
  } else {
    display.setTextColor(SSD1306_WHITE, SSD1306_BLACK); // Normal text
  }

  // Print the text
  display.setCursor(cursorX, cursorY);
  display.print(text);

  // Move cursor to the right after the printed text
  cursorX += textWidth;

  // Reset text color
  display.setTextColor(SSD1306_WHITE, SSD1306_BLACK);
}

void customPrintln(const char* text, bool invert) {
  int textWidth = strlen(text) * charWidth;

  if (invert) {
    // Draw inversion background for the entire line
    display.fillRect(0, cursorY, SCREEN_WIDTH, charHeight, SSD1306_WHITE);
    display.setTextColor(SSD1306_BLACK, SSD1306_WHITE); // Inverted text
  } else {
    display.setTextColor(SSD1306_WHITE, SSD1306_BLACK); // Normal text
  }

  // Print the text
  display.setCursor(cursorX, cursorY);
  display.print(text);

  // Move to the next line
  cursorX = 0;
  cursorY += charHeight;
}
// end2 utils.cpp

// start2 menu.cpp
String basename(String path, bool removeExt = false) {
  int lastSlash = path.lastIndexOf('/');
  String name = (lastSlash != -1) ? path.substring(lastSlash + 1) : path;

  if (removeExt) {
    int dotIndex = name.lastIndexOf('.');
    if (dotIndex != -1) {
      name = name.substring(0, dotIndex);
    }
  }

  name.replace("/", "");

  return name;
}

std::vector<String> listContents(String& files) {
  int currentDepth = 0;
  int lastDepth = 0;
  String currentPath = "/";
  String itemName = "";
  String itemPath = "";
  currentPath.reserve(100);  // Reserve memory for currentPath to avoid resizing
  itemName.reserve(50);
  itemPath.reserve(50);

  std::vector<String> vec;

  for (int i = 0; i < files.length(); i++) {
    int lineEnd = files.indexOf('\n', i);
    if (lineEnd == -1) lineEnd = files.length();
    String line = files.substring(i, lineEnd);
    i = lineEnd;

    currentDepth = 0;
    while (line[currentDepth] == ' ') currentDepth++;

    if (currentDepth == 0) {
      currentPath = "/";
      lastDepth = 0;
    }

    while (currentDepth < lastDepth) {
      Serial.println(currentPath);
      currentPath = goBackInPath(currentPath);  // Move up a level
      Serial.println(currentPath);
      lastDepth--;
    }

    lastDepth = currentDepth;

    bool isFolder = line[currentDepth] == 'd';
    itemName = line.substring(currentDepth + 2);
    itemPath = (isFolder ? "d" : "f") + currentPath + itemName;  // Avoid concatenating too often

    vec.push_back(itemPath);

    if (isFolder) {
      currentDepth++;
      currentPath += itemName + "/";  // Avoid frequent resizing
    }
  }

  itemName.remove(0);
  itemPath.remove(0);

  return vec;
}

String goBackInPath(String path) {
  if (path == "/") {
    return "/";
  }
  int lastSlashIndex = path.lastIndexOf('/', path.length() - 2);  // Find previous folder
  return path.substring(0, lastSlashIndex + 1);  // Keep trailing '/'
}

#define JOYSTICK_X_PIN 34   // X-axis (left/right) - digital pin (not used yet)
#define JOYSTICK_Y_PIN 35   // Y-axis (up/down) - digital pin
#define JOYSTICK_BUTTON_PIN 32

std::vector<String> vec = listContents(files);
std::vector<bool> types(vec.size(), false);
// end2 menu.cpp

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

  // Initialize the OLED display
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }
  display.display();

  pinMode(JOYSTICK_BUTTON_PIN, INPUT_PULLUP);

  display.clearDisplay();
  display.display();

  // start3 menu.cpp
  for (int i = 0; i < vec.size(); i++) {
    types[i] = vec[i].startsWith("d");
    Serial.println(vec[i]);
  }
  // end3 menu.cpp
}

// start controls.cpp
bool yPlusPressed = false;
bool yMinusPressed = false;
bool xPlusPressed = false;
bool xMinusPressed = false;
bool lastClicked = false;
// end controls.cpp

// start4 menu.cpp
bool firstTime = true;
String lastPath = "/";
String currentPath = "/";

int visibleStartIndex = 0;  // Start index for visible lines
#define MAX_VISIBLE_LINES 8   // Number of lines visible on the screen

std::vector<String> results = {};
std::vector<bool> resultTypes = {};
// end4 menu.cpp

void loop() {
  // start controls.cpp 
  int yValue = analogRead(JOYSTICK_Y_PIN);  // Read Y-axis (up/down)
  int xValue = analogRead(JOYSTICK_X_PIN);
  int clicked = digitalRead(JOYSTICK_BUTTON_PIN) == LOW;
  // end controls.cpp


  // start5 menu.cpp

  if (vec.size() > 0) {
    // Update cursor position
    cursorY = 0;
    int moved = 0;
    while ((selectedIndex * charHeight) >= moved + SCREEN_HEIGHT) {
      moved += charHeight;  // Move the cursor up
      cursorY -= charHeight;
    }

    // Scroll down if needed
    while ((selectedIndex * charHeight) <= moved - ((MAX_VISIBLE_LINES - 1) * charHeight)) {
      moved -= charHeight;  // Move the cursor down
      cursorY += charHeight;
    }

    // Display updated items only if necessary
    if ((clicked != lastClicked && clicked == false) || yPlusPressed || yMinusPressed || firstTime || path != lastPath) {
      display.clearDisplay();

      int currentIndex = 0;

      results.clear();
      resultTypes.clear();

      for (int i = 0; i < vec.size(); i++) {
        int lastIndexOfSlash = -1;
        lastIndexOfSlash = vec[i].lastIndexOf('/');

        currentPath = vec[i].substring(1, lastIndexOfSlash + 1);

        if (path != "/" && i == 0) {
          customPrintln("..", currentIndex == selectedIndex);
          results.push_back("..");
          resultTypes.push_back(true);

          currentIndex++;
          continue;
        }
        if (currentPath == path) {
          cursorX = charWidth * 2;

          customPrintln(basename(vec[i]).c_str(), currentIndex == selectedIndex);

          cursorX = 0;
          cursorY -= charHeight;
          display.drawBitmap(cursorX, cursorY, types[i] ? folderIcon : fileIcon, 8, 8, currentIndex == selectedIndex ? BLACK : WHITE);
          cursorY += charHeight;


          results.push_back(basename(vec[i]));
          resultTypes.push_back(types[i]);

          currentIndex++;
        }
      }
      display.display();

      firstTime = false;
      lastPath = path;
    }
  }

  int resultCount = results.size();

  firstTime = true;

  // Handle wrap-around logic for selection index
  if (selectedIndex >= resultCount) {
    selectedIndex = 0;  // Wrap around to the first element
  } else if (selectedIndex < 0) {
    selectedIndex = resultCount - 1;  // Wrap around to the last element
  } else {
    firstTime = false;
  }

  // end5 menu.cpp

  // start controls.cpp

  // Joystick Y-axis movement (up/down)
  if (yValue < 1000 && !yPlusPressed) {  // Joystick moved down
    selectedIndex++;
    yPlusPressed = true;
  } else if (yValue >= 1000 && yValue <= 3000) {  // Reset flag in neutral position
    yPlusPressed = false;
  }

  if (yValue > 3000 && !yMinusPressed) {  // Joystick moved up
    selectedIndex--;
    yMinusPressed = true;
  } else if (yValue >= 1000 && yValue <= 3000) {  // Reset flag in neutral position
    yMinusPressed = false;
  }

  // X-Movement (left/right)
  if (xValue < 1000 && !xPlusPressed) {  // Joystick moved right
    xPlusPressed = true;
  } else if (xValue >= 1000 && xValue <= 3000) {  // Reset flag in neutral position
    xPlusPressed = false;
  }

  if (xValue > 3000 && !xMinusPressed) {  // Joystick moved left
    xMinusPressed = true;
  } else if (xValue >= 1000 && xValue <= 3000) {  // Reset flag in neutral position
    xMinusPressed = false;
  }

  // Handle click action
  if (clicked != lastClicked && clicked == false) {
    if (results[selectedIndex] == "..") {
      path = goBackInPath(path);
    } else if (resultTypes[selectedIndex] == true) {
      path = path + results[selectedIndex] + "/";
      selectedIndex = 0;
    }
  }

  lastClicked = clicked;

  // end controls.cpp

  delay(50);
}