#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <MPU6050.h>


// OLED Display settings
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);


// MPU6050
MPU6050 mpu;


// Pin definitions - CORRECTED for your Wokwi circuit
// Physical layout: [LDR5] [LDR2] [LDR1] [LDR3] [LDR4]
const int LDR_PINS[5] = {D0, D1, D2, D3, D10};  // LDR5, LDR2, LDR1, LDR3, LDR4
const int BUTTON_1 = D8;  // Green button
const int BUTTON_2 = D9;  // Red button


// Sensor data
int ldrValues[5];
int16_t ax, ay, az;
int16_t gx, gy, gz;


// Gesture recognition
#define MAX_GESTURES 10


struct GesturePattern {
  String word;
  int ldrThresholds[5][2];      // min, max for each LDR
  int motionThresholds[3][2];   // min, max for ax, ay, az
  bool useMotion;
};


// Dictionary of gestures - CUSTOMIZED FOR YOUR LAYOUT
GesturePattern dictionary[MAX_GESTURES] = {
 
  // HELLO: All medium light + device tilted UP (screen facing sky)
  {
    "HELLO",
    {{800, 3000}, {800, 3000}, {800, 3000}, {800, 3000}, {800, 3000}},
    {{-4000, 4000}, {-4000, 4000}, {12000, 20000}},  // Tilted up
    true
  },
 
  // YES: Center dark (cover middle LDRs) + tilted down
  {
    "YES",
    {{1000, 4095},  // LDR5: bright
     {0, 800},      // LDR2: dark
     {0, 800},      // LDR1: dark
     {0, 800},      // LDR3: dark
     {1000, 4095}}, // LDR4: bright
    {{-3000, 3000}, {-3000, 3000}, {-20000, -10000}},  // Tilted down
    true
  },
 
  // NO: Edges dark + tilted left/right
  {
    "NO",
    {{0, 800},      // LDR5: dark
     {1000, 4095},  // LDR2: bright
     {1000, 4095},  // LDR1: bright
     {1000, 4095},  // LDR3: bright
     {0, 800}},     // LDR4: dark
    {{-20000, 20000}, {-3000, 3000}, {-3000, 3000}},  // Rotated
    true
  },
 
  // LIGHT: All sensors detect bright light
  {
    "LIGHT",
    {{2800, 4095}, {2800, 4095}, {2800, 4095}, {2800, 4095}, {2800, 4095}},
    {{-5000, 5000}, {-5000, 5000}, {-5000, 5000}},
    false  // No motion needed
  },
 
  // DARK: All sensors covered/dark
  {
    "DARK",
    {{0, 600}, {0, 600}, {0, 600}, {0, 600}, {0, 600}},
    {{-5000, 5000}, {-5000, 5000}, {-5000, 5000}},
    false
  },
 
  // WAVE: Progressive light pattern (left to right)
  {
    "WAVE",
    {{0, 800},      // LDR5: darkest
     {800, 1600},   // LDR2
     {1600, 2400},  // LDR1: center
     {2400, 3200},  // LDR3
     {3200, 4095}}, // LDR4: brightest
    {{-5000, 5000}, {-5000, 5000}, {-5000, 5000}},
    false
  },
 
  // UP: Device tilted strongly upward
  {
    "UP",
    {{0, 4095}, {0, 4095}, {0, 4095}, {0, 4095}, {0, 4095}},  // Any light
    {{-4000, 4000}, {-4000, 4000}, {14000, 20000}},  // Strong tilt up
    true
  },
 
  // DOWN: Device tilted strongly downward
  {
    "DOWN",
    {{0, 4095}, {0, 4095}, {0, 4095}, {0, 4095}, {0, 4095}},
    {{-4000, 4000}, {-4000, 4000}, {-20000, -14000}},  // Strong tilt down
    true
  }
};


int activeDictionarySize = 8;  // Number of active gestures


// Timing for gesture display
unsigned long lastMatchTime = 0;
String lastMatchedWord = "";


void setup() {
  Serial.begin(115200);
  delay(1000);
 
  // Initialize I2C
  Wire.begin(D4, D5);  // SDA, SCL
 
  // Initialize OLED
  if(!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
 
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println(F("Gesture System"));
  display.println(F("Initializing..."));
  display.display();
  delay(2000);
 
  // Initialize MPU6050
  mpu.initialize();
  if (!mpu.testConnection()) {
    Serial.println(F("MPU6050 connection failed"));
    display.clearDisplay();
    display.setCursor(0, 0);
    display.println(F("MPU6050 ERROR!"));
    display.display();
    for(;;);
  }
 
  mpu.setFullScaleAccelRange(MPU6050_ACCEL_FS_2);
  mpu.setFullScaleGyroRange(MPU6050_GYRO_FS_250);
 
  // Initialize LDR pins
  for (int i = 0; i < 5; i++) {
    pinMode(LDR_PINS[i], INPUT);
  }
 
  // Initialize buttons - ACTIVE HIGH with internal pull-down
  pinMode(BUTTON_1, INPUT_PULLDOWN);
  pinMode(BUTTON_2, INPUT_PULLDOWN);
 
  display.clearDisplay();
  display.setCursor(0, 0);
  display.println(F("Ready!"));
  display.println(F(""));
  display.println(F("Green: Info"));
  display.println(F("Red: Reset"));
  display.println(F(""));
  display.print(F("Gestures: "));
  display.println(activeDictionarySize);
  display.display();
  delay(2000);
 
  Serial.println("\n=================================");
  Serial.println("GESTURE RECOGNITION SYSTEM READY");
  Serial.println("=================================");
  Serial.println("Physical LDR Layout:");
  Serial.println("[LDR5] [LDR2] [LDR1] [LDR3] [LDR4]");
  Serial.println("  D0     D1     D2     D3     D10");
  Serial.println("\nAvailable Gestures:");
  for (int i = 0; i < activeDictionarySize; i++) {
    Serial.print("- ");
    Serial.println(dictionary[i].word);
  }
  Serial.println("=================================\n");
}


void loop() {
  // Check buttons
  if (digitalRead(BUTTON_1) == HIGH) {
    showInfo();
    delay(300);  // Debounce
  }
 
  if (digitalRead(BUTTON_2) == HIGH) {
    resetDisplay();
    delay(300);  // Debounce
  }
 
  // Read sensors
  readSensors();
 
  // Check for gesture match
  String matchedWord = matchGesture();
 
  // Display result
  if (matchedWord != "") {
    displayWord(matchedWord);
    lastMatchTime = millis();
    lastMatchedWord = matchedWord;
    delay(1500);  // Show word for 1.5 seconds
  } else {
    // Show sensor data if no recent match
    if (millis() - lastMatchTime > 3000) {
      displaySensorData();
    }
  }
 
  delay(150);  // Update rate
}


void readSensors() {
  // Read LDR values
  for (int i = 0; i < 5; i++) {
    ldrValues[i] = analogRead(LDR_PINS[i]);
  }
 
  // Read MPU6050
  mpu.getMotion6(&ax, &ay, &az, &gx, &gy, &gz);
 
  // Debug output
  Serial.print("LDR: ");
  for (int i = 0; i < 5; i++) {
    Serial.print(ldrValues[i]);
    Serial.print(" ");
  }
  Serial.print(" | Motion: AX=");
  Serial.print(ax);
  Serial.print(" AY=");
  Serial.print(ay);
  Serial.print(" AZ=");
  Serial.println(az);
}


String matchGesture() {
  for (int i = 0; i < activeDictionarySize; i++) {
    bool ldrMatch = true;
    bool motionMatch = true;
   
    // Check LDR thresholds
    for (int j = 0; j < 5; j++) {
      if (ldrValues[j] < dictionary[i].ldrThresholds[j][0] ||
          ldrValues[j] > dictionary[i].ldrThresholds[j][1]) {
        ldrMatch = false;
        break;
      }
    }
   
    // Check motion thresholds if required
    if (dictionary[i].useMotion) {
      if (ax < dictionary[i].motionThresholds[0][0] || ax > dictionary[i].motionThresholds[0][1] ||
          ay < dictionary[i].motionThresholds[1][0] || ay > dictionary[i].motionThresholds[1][1] ||
          az < dictionary[i].motionThresholds[2][0] || az > dictionary[i].motionThresholds[2][1]) {
        motionMatch = false;
      }
    }
   
    // If both match, return the word
    if (ldrMatch && motionMatch) {
      Serial.print(">>> MATCH: ");
      Serial.println(dictionary[i].word);
      return dictionary[i].word;
    }
  }
 
  return "";  // No match
}


void displayWord(String word) {
  display.clearDisplay();
  display.setTextSize(3);
  display.setTextColor(SSD1306_WHITE);
 
  // Center the word
  int16_t x1, y1;
  uint16_t w, h;
  display.getTextBounds(word, 0, 0, &x1, &y1, &w, &h);
  display.setCursor((SCREEN_WIDTH - w) / 2, (SCREEN_HEIGHT - h) / 2);
  display.println(word);
 
  // Add small indicator
  display.setTextSize(1);
  display.setCursor(0, SCREEN_HEIGHT - 10);
  display.print(F("Detected!"));
 
  display.display();
}


void displaySensorData() {
  display.clearDisplay();
  display.setTextSize(1);
  display.setCursor(0, 0);
 
  // Header
  display.println(F("Sensor Monitor"));
  display.println(F("-------------"));
 
  // LDR values - show physical layout
  display.println(F("LDR (D0-D1-D2-D3-D10):"));
  for (int i = 0; i < 5; i++) {
    display.print(ldrValues[i] / 10);  // Scale for display
    if (i < 4) display.print("-");
  }
  display.println();
 
  // Motion data
  display.print(F("Motion: "));
  display.print(ax / 1000);
  display.print(F(","));
  display.print(ay / 1000);
  display.print(F(","));
  display.println(az / 1000);
 
  display.println();
  display.println(F("Perform gesture..."));
 
  display.display();
}


void showInfo() {
  display.clearDisplay();
  display.setTextSize(1);
  display.setCursor(0, 0);
 
  display.println(F("Gesture System"));
  display.println(F("-------------"));
  display.print(F("Gestures: "));
  display.println(activeDictionarySize);
  display.println();
 
  // Show first 5 gestures
  for (int i = 0; i < min(5, activeDictionarySize); i++) {
    display.print(F("- "));
    display.println(dictionary[i].word);
  }
 
  if (activeDictionarySize > 5) {
    display.print(F("+ "));
    display.print(activeDictionarySize - 5);
    display.println(F(" more..."));
  }
 
  display.display();
  delay(3000);
}


void resetDisplay() {
  display.clearDisplay();
  display.setTextSize(2);
  display.setCursor(20, 20);
  display.println(F("RESET"));
  display.display();
 
  lastMatchTime = 0;
  lastMatchedWord = "";
 
  delay(1000);
}