/**
 * @file ESP32_DasaiMochi.ino
 * @brief Main sketch for Dasai Mochi - Interactive Expression Display
 * 
 * Hardware:
 * - ESP32 Development Board
 * - SSD1306 OLED Display (128x64, I2C)
 * - TTP223 Touch Sensor
 * - MPU6050 Accelerometer/Gyroscope
 * 
 * Behavior:
 * - Standby: Random expressions (Normal, Happy, Sad, Sleepy, Loving, Surprised)
 * - Touch: Changes to surprised expression while touched
 * - Shake: Becomes dizzy, then angry if shaking continues
 * 
 * @author Tukucode
 * @version 1
 * @date 2026
 */

#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>

// Project headers
#include "config.h"

// Global display instance
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Include modules after display is declared
#include "expressions.h"
#include "sensors.h"
#include "state_machine.h"
#include "ai_service.h"
#include "sounds.h"

// Debug flag
#define DEBUG_MODE true

/**
 * @brief Setup function - runs once at startup
 */
void setup() {
  // Initialize serial for debugging
  Serial.begin(115200);
  delay(100);
  
  Serial.println();
  Serial.println("================================");
  Serial.println("  Tuku Mochi v1 - Starting Up!  ");
  Serial.println("================================");
  
  // Initialize I2C
  Wire.begin(SDA_PIN, SCL_PIN);
  
  // Initialize OLED display
  if (!display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDRESS)) {
    Serial.println("ERROR: SSD1306 allocation failed!");
    // Show error on serial and halt
    while (true) {
      Serial.println("Display init failed. Check wiring.");
      delay(1000);
    }
  }
  Serial.println("OLED display initialized");
  
  // Clear display and show startup
  display.clearDisplay();
  display.setTextSize(2);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(5, 15);
  display.println("Tuku Mochi");
  display.setTextSize(1);
  display.setCursor(30, 45);
  display.println("by Tukucode");
  display.display();
  delay(2000);
  
  // Initialize MPU6050
  if (!initMPU6050()) {
    Serial.println("WARNING: MPU6050 not found. Shake detection disabled.");
    display.clearDisplay();
    display.setCursor(10, 25);
    display.println("MPU6050 not found");
    display.setCursor(10, 40);
    display.println("Shake disabled");
    display.display();
    delay(1500);
  }
  
  // Initialize touch sensor
  initTouchSensor();
  
  // Initialize LDR sensor
  initLDRSensor();
  
  // Initialize buzzer
  pinMode(BUZZER_PIN, OUTPUT);
  noTone(BUZZER_PIN);
  
  // Initialize WiFi for AI
  initWiFi();
  
  // Create background AI task
  xTaskCreate(
    aiBackgroundTask,    /* Task function. */
    "AITask",            /* name of task. */
    8192,                /* Stack size of task */
    NULL,                /* parameter of the task */
    1,                   /* priority of the task */
    &aiTaskHandle        /* Task handle to keep track of created task */
  );
  
  // Initialize random seed
  randomSeed(analogRead(0));
  
  // Load persistent settings (Brightness, Invert)
  loadPersistentSettings();
  
  // Start in standby state with initial expression
  transitionToState(STATE_STANDBY);
  
  Serial.println("================================");
  Serial.println("  Initialization Complete!     ");
  Serial.println("================================");
  Serial.println();
}

/**
 * @brief Main loop - runs continuously
 */
void loop() {
  // Update the state machine (handles all logic)
  updateStateMachine();
  
  // Handle AI Serial Communication
  handleSerialAI();
  
  // Debug output (every 2 seconds)
  #if DEBUG_MODE
  static unsigned long lastDebugTime = 0;
  if (millis() - lastDebugTime > 2000) {
    Serial.print("State: ");
    Serial.print(getStateName());
    Serial.print(" | Expression: ");
    Serial.print(getExpressionName());
    Serial.print(" | Touch: ");
    Serial.print(isTouchActive() ? "YES" : "NO");
    Serial.print(" | LDR: ");
    Serial.println(isLDRActive() ? "YES" : "NO");
    Serial.print(" | Shake: ");
    Serial.println(isShaking() ? "YES" : "NO");
    lastDebugTime = millis();
  }
  #endif
  
  // Small delay to prevent CPU hogging
  delay(10);
}