#include <TFT_eSPI.h>

// 定義 TFT_eSPI 函式庫使用的 TFT 連接接腳
#define TFT_CS    5
#define TFT_RST   2
#define TFT_DC    15

// 初始化 TFT 物件
TFT_eSPI tft = TFT_eSPI();

// 中心座標
#define CENTER_X 160
#define CENTER_Y 120
// 大紅點半徑
#define BIG_DOT_RADIUS 7
// 小紅點半徑
#define SMALL_DOT_RADIUS 3

unsigned long pTime_g = 0;
int generate = 1500;

void setup() {
  // 初始化 TFT 顯示
  tft.begin();
  tft.setRotation(1); // 設定顯示旋轉方向

  // 設定背景為黑色
  tft.fillScreen(TFT_BLACK);

  // 畫一個紅色的填滿圓在畫面中心
  tft.fillCircle(CENTER_X, CENTER_Y, BIG_DOT_RADIUS, TFT_RED);
}

unsigned long lastMoveTime = 0;
bool dotsGenerated = false;
int generatedX[5];
int generatedY[5];
float generatedAngles[5]; // 儲存每個小紅點的生成角度
int speed;
int count = 5; // 預設生成 5 個小紅點

void loop() {
  if (millis() - pTime_g > generate) {
    clearRemainingDots();  // 清除所有未達到邊界的小紅點
    generateSmallDots(count);
    pTime_g = millis();
    lastMoveTime = millis();  // 記錄生成時間
    dotsGenerated = true;     // 標記小紅點已生成
  }

  // 檢查是否需要移動小紅點
  if (dotsGenerated) {
    moveSmallDots();
  }
}

void clearRemainingDots() {
  for (int i = 0; i < count; i++) {
    // 清除畫面上的小紅點
    tft.fillCircle(generatedX[i], generatedY[i], SMALL_DOT_RADIUS, TFT_BLACK);
  }
}

void generateSmallDots(int count) {
  int distance = random(10, 31);
  speed = random(1, 6);  // 隨機選擇移動速度

  float angleIncrement = 2 * PI / count;
  float currentAngle = 0;

  for (int i = 0; i < count; i++) {
    int smallDotX = CENTER_X + cos(currentAngle) * distance;
    int smallDotY = CENTER_Y + sin(currentAngle) * distance;

    generatedX[i] = smallDotX;
    generatedY[i] = smallDotY;
    generatedAngles[i] = currentAngle; // 儲存生成角度

    tft.fillCircle(smallDotX, smallDotY, SMALL_DOT_RADIUS, TFT_RED);
    currentAngle += angleIncrement;
  }
}

unsigned long lastUpdateTime = 0;
const int updateInterval = 30;

void moveSmallDots() {
  if (millis() - lastUpdateTime < updateInterval) return;
  lastUpdateTime = millis();

  bool allMoved = true;
  for (int i = 0; i < count; i++) {
    int smallDotX = generatedX[i];
    int smallDotY = generatedY[i];
    float angle = generatedAngles[i];

    // 根據角度更新位置
    smallDotX += cos(angle) * speed;
    smallDotY += sin(angle) * speed;

    if (smallDotX - SMALL_DOT_RADIUS <= 0 || smallDotX + SMALL_DOT_RADIUS >= tft.width() ||
        smallDotY - SMALL_DOT_RADIUS <= 0 || smallDotY + SMALL_DOT_RADIUS >= tft.height()) {
      tft.fillCircle(generatedX[i], generatedY[i], SMALL_DOT_RADIUS + 2, TFT_BLACK);
    } else {
      tft.fillCircle(generatedX[i], generatedY[i], SMALL_DOT_RADIUS, TFT_BLACK);
      tft.fillCircle(smallDotX, smallDotY, SMALL_DOT_RADIUS, TFT_RED);

      generatedX[i] = smallDotX;
      generatedY[i] = smallDotY;

      allMoved = false;
    }
  }

  dotsGenerated = !allMoved;
}