#include <SPI.h>
#include <Adafruit_GFX.h>
#include <Adafruit_ILI9341.h>
#include <LiquidCrystal_I2C.h>

#define TFT_CS   10
#define TFT_DC    9
#define TFT_RST   8
Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_RST);

LiquidCrystal_I2C lcd(0x27, 16, 2);
#define BTN_THEME 2

// ========================================
// EASY AM/PM SWITCH - CHANGE THIS LINE ONLY!
// ========================================
String timeMode = "AM";  // ← "AM" or "PM" LANG!
int hours = 11, minutes = 00, seconds = 00, day = 20;  // 11:59:55 PM (use 1-12 for hours)

unsigned long prevMillis = 0;
int currentThemeIndex = 0;  // 0=Classic, 1=Neon, 2=Retro

// 3 ANALOG CLOCK THEMES (Background FIXED by AM/PM)
struct ClockTheme {
  uint16_t rim, handH, handM, handS, center, hourMarkers;
  String name;
};

// Define your themes
ClockTheme clockThemes[3] = {
  // Theme 0: CLASSIC
  {ILI9341_MAROON, ILI9341_BLACK, ILI9341_BLACK, ILI9341_RED, ILI9341_YELLOW, ILI9341_WHITE, "CLASSIC"},
  // Theme 1: NEON
  {ILI9341_PURPLE, ILI9341_MAGENTA, ILI9341_YELLOW, ILI9341_WHITE, ILI9341_CYAN, ILI9341_LIGHTGREY, "NEON"},
  // Theme 2: RETRO
  {ILI9341_PINK, ILI9341_RED, ILI9341_BLUE, ILI9341_GREEN, ILI9341_WHITE, ILI9341_YELLOW, "RETRO"}
};

int cx = 120, cy = 120;
unsigned long lastBtnPress = 0;

// Store last positions for erasing
float lastHourAngle = 0, lastMinuteAngle = 0, lastSecondAngle = 0;

// Function declarations
void setBackground();
void drawSunMoon();
void drawClockFace();
void drawThemeIndicator();
void updateClockHands();
void updateLCD();
void updateThemeByTime();

void setup() {
  Serial.begin(9600);
  pinMode(BTN_THEME, INPUT_PULLUP);
  
  tft.begin();
  tft.setRotation(0);
  setBackground();  // Initial background based on time
  lcd.init();
  lcd.backlight();
  lcd.clear();
  
  drawSunMoon();
  drawClockFace();
  drawThemeIndicator();
  
  // Initialize last angles
  lastHourAngle = (hours % 12) * 30 + minutes * 0.5;
  lastMinuteAngle = minutes * 6 + seconds * 0.1;
  lastSecondAngle = seconds * 6;
  
  Serial.println("✅ Fixed BG Clock - Press button to cycle clock themes");
}

void loop() {
  unsigned long currentMillis = millis();
  if (currentMillis - prevMillis >= 1000) {
    prevMillis = currentMillis;
    int oldHours = hours;
    seconds++;
    if (seconds >= 60) { 
      seconds = 0; 
      minutes++; 
    }
    if (minutes >= 60) { 
      minutes = 0; 
      hours = (hours + 1) % 24;
    }
    if (hours == 0 && minutes == 0) { 
      day++; 
    }
    // Fire full auto AM/PM transitions
    if (oldHours == 11 && hours == 12) {
      timeMode = "PM";
      Serial.println("☀️ NOON! 11:59AM → 12:00PM");
      updateBackground();
      drawSunMoon();
      drawClockFace();
      currentThemeIndex = 0;
    }
    if (oldHours == 23 && hours == 0) {
      timeMode = "AM";
      Serial.println("🌙 MIDNIGHT! 11:59PM → 12:00AM");
      updateBackground();
      drawSunMoon();
      drawClockFace();
      currentThemeIndex = 0;
    }
    updateClockHands();
    updateLCD();

    // Update theme based on time of day
    updateThemeByTime();
  }

  // Theme button
  if (digitalRead(BTN_THEME) == LOW && millis() - lastBtnPress > 300) {
    currentThemeIndex = (currentThemeIndex + 1) % 3;
    drawClockFace();
    drawThemeIndicator();
    lastBtnPress = millis();
    Serial.println("Theme: " + getCurrentTheme().name);
  }
}

// Function definitions

void setBackground() {
  if (timeMode == "AM") {
    tft.fillScreen(ILI9341_WHITE);
  } else {
    tft.fillScreen(ILI9341_BLACK);
  }
}

void updateBackground() {
  setBackground();
}

void drawSunMoon() {
  int iconX = 230, iconY=30;
  if (timeMode == "AM") {
    // Sun
    tft.fillCircle(iconX, iconY, 12, ILI9341_YELLOW);
    tft.drawCircle(iconX, iconY, 14, ILI9341_ORANGE);
    for (int i=0; i<8; i++) {
      float angle = i*0.7854;
      int x1 = iconX + cos(angle)*18;
      int y1 = iconY + sin(angle)*18;
      int x2 = iconX + cos(angle)*22;
      int y2 = iconY + sin(angle)*22;
      tft.drawLine(x1,y1,x2,y2, ILI9341_YELLOW);
    }
  } else {
    // Moon
    tft.fillCircle(iconX, iconY, 10, ILI9341_WHITE);
    tft.drawCircle(iconX, iconY, 12, ILI9341_LIGHTGREY);
    tft.fillCircle(iconX-3, iconY+2, 2, ILI9341_DARKGREY);
    tft.fillCircle(iconX+4, iconY-1, 2, ILI9341_DARKGREY);
  }
}

void drawClockFace() {
  ClockTheme theme = getCurrentTheme();
  uint16_t bgColor = (timeMode == "AM") ? ILI9341_WHITE : ILI9341_BLACK;
  // Draw rim and center
  tft.fillCircle(cx, cy, 118, theme.rim);
  tft.fillCircle(cx, cy, 5, theme.center);
  for (int i=0; i<12; i++) {
    float angle = i * 0.5236; // approx 30 degrees in radians
    int x1 = cx + cos(angle) * 105;
    int y1 = cy + sin(angle) * 105;
    int x2 = cx + cos(angle) * 90;
    int y2 = cy + sin(angle) * 90;
    tft.drawLine(x1, y1, x2, y2, theme.hourMarkers);
  }
}

void drawThemeIndicator() {
  uint16_t textColor = (timeMode == "AM") ? ILI9341_BLACK : ILI9341_WHITE;
  uint16_t bgColor = (timeMode == "AM") ? ILI9341_WHITE : ILI9341_BLACK;
  tft.fillRect(5, 285, 230, 15, bgColor);
  tft.setTextColor(textColor);
  tft.setTextSize(1);
  tft.setCursor(10, 288);
  tft.print("Mode: ");
  tft.print(timeMode);
  tft.print(" | ");
  tft.print(getCurrentTheme().name);
}

void updateClockHands() {
  ClockTheme theme = getCurrentTheme();
  uint16_t bgColor = (timeMode == "AM") ? ILI9341_WHITE : ILI9341_BLACK;

  float hourAngle = (hours % 12) * 30 + minutes * 0.5;
  float minuteAngle = minutes * 6 + seconds * 0.1;
  float secondAngle = seconds * 6;

  // Erase old
  drawHand(lastHourAngle, 70, bgColor);
  drawHand(lastMinuteAngle, 95, bgColor);
  drawHand(lastSecondAngle, 105, bgColor);

  // Draw new
  drawHand(hourAngle, 70, theme.handH);
  drawHand(minuteAngle, 95, theme.handM);
  drawHand(secondAngle, 105, theme.handS);

  lastHourAngle = hourAngle;
  lastMinuteAngle = minuteAngle;
  lastSecondAngle = secondAngle;

  // Center dot
  tft.fillCircle(cx, cy, 5, theme.center);
}

void drawHand(float angleDeg, int length, uint16_t color) {
  float angleRad = (angleDeg - 90) * PI / 180;
  int x2 = cx + cos(angleRad) * length;
  int y2 = cy + sin(angleRad) * length;
  tft.drawLine(cx, cy, x2, y2, color);
  if (length == 70) {
    tft.drawLine(cx+1, cy, x2+1, y2, color);
    tft.drawLine(cx-1, cy, x2-1, y2, color);
  }
  if (length == 95) {
    tft.drawLine(cx+1, cy, x2+1, y2, color);
  }
}

void updateLCD() {
  lcd.clear();
  lcd.setCursor(0, 0);
  int displayHour = hours;
  String ampm = timeMode;
  if (displayHour < 10) lcd.print("0");
  lcd.print(displayHour);
  lcd.print(":");
  if (minutes < 10) lcd.print("0");
  lcd.print(minutes);
  lcd.print(":");
  if (seconds < 10) lcd.print("0");
  lcd.print(seconds);
  lcd.print(" ");
  lcd.print(ampm);
  lcd.setCursor(0, 1);
  String monthName = "Feb";
  lcd.print(monthName); 
  lcd.print(" "); 
  lcd.print(day); 
  lcd.print(", 2026");
}

void updateThemeByTime() {
  int totalMinutes = hours * 60 + minutes; // total minutes since midnight
  int morningStart = 6 * 60; // 6:00 AM
  int morningEnd = 17 * 60 + 59; // 5:59 PM
  int eveningStart = 18 * 60; // 6:00 PM
  int eveningEnd = 23 * 60 + 59; // 11:59 PM

  if (totalMinutes >= morningStart && totalMinutes <= morningEnd) {
    // Daytime: white theme
    if (timeMode != "AM") {
      timeMode = "AM";
      updateBackground();
      drawSunMoon();
      drawClockFace();
      drawThemeIndicator();
    }
  } else {
    // Nighttime: black theme
    if (timeMode != "PM") {
      timeMode = "PM";
      updateBackground();
      drawSunMoon();
      drawClockFace();
      drawThemeIndicator();
    }
  }
}

ClockTheme getCurrentTheme() {
  return clockThemes[currentThemeIndex];
}