/*

  WaveShare 1.8" SPI Display (ST7735S) — Quick Demo

  Board: Arduino UNO / Nano (5V). Works with any AVR/ESP; adjust pins as needed.

  Libraries (install via Library Manager):

    - Adafruit GFX Library

    - Adafruit ST7735 and ST7789 Library

  Typical Waveshare pinout:

    VCC  -> 5V (or 3.3V, module dependent)

    GND  -> GND

    DIN  -> MOSI (UNO D11)

    CLK  -> SCK  (UNO D13)

    CS   -> D10  (TFT_CS)

    DC   -> D9   (TFT_DC)

    RST  -> D8   (TFT_RST)

    BL   -> 3.3V (or a PWM-capable pin via 100-330Ω if you want dimming)

  Notes:

   - ST7735S often uses INITR_BLACKTAB; if colors look off, try INITR_GREENTAB or INITR_18GREENTAB.

   - Set rotation to 1 for landscape 160x128; 0 for portrait 128x160.

*/

#include <Adafruit_GFX.h>

#include <Adafruit_ST7735.h>

#include <SPI.h>

// ---------- Pin configuration (UNO defaults) ----------

#define TFT_CS   10

#define TFT_DC    9

#define TFT_RST   8   // You can use -1 if RST is tied to Arduino RESET

Adafruit_ST7735 tft(TFT_CS, TFT_DC, TFT_RST);

// ---------- Handy colors ----------

#define C_BG   ST77XX_BLACK

#define C_TXT  ST77XX_WHITE

#define C_ACC  ST77XX_CYAN

#define C_RED  ST77XX_RED

#define C_GRN  ST77XX_GREEN

#define C_BLU  ST77XX_BLUE

#define C_YEL  ST77XX_YELLOW

#define C_MAG  ST77XX_MAGENTA

// ---------- Optional: backlight PWM (comment out if BL tied to VCC) ----------

// #define TFT_BL   5   // pick a PWM pin if you wired BL to a pin

// uint8_t backlight = 255; // 0-255

void demoPrimitives() {

  tft.fillScreen(C_BG);

  // Borders

  tft.drawRect(0, 0, tft.width(), tft.height(), C_ACC);

  tft.drawRect(2, 2, tft.width()-4, tft.height()-4, ST77XX_DARKGREY);

  // Lines

  for (int i=0; i< tft.width(); i+=10) {

    tft.drawLine(0, 0, i, tft.height()-1, C_BLU);

  }

  delay(500);

  tft.fillRect(0, 0, tft.width(), tft.height(), C_BG);

  // Circles

  for (int r=4; r< (tft.height()/2); r+=6) {

    tft.drawCircle(tft.width()/2, tft.height()/2, r, C_GRN);

  }

  delay(500);

  // Filled rectangles

  tft.fillRect(6, 6, 40, 30, C_RED);

  tft.fillRect(52, 6, 40, 30, C_GRN);

  tft.fillRect(98, 6, 40, 30, C_BLU);

  delay(500);

}

void demoText() {

  tft.fillScreen(C_BG);

  tft.setCursor(2, 2);

  tft.setTextColor(C_TXT);

  tft.setTextWrap(true);

  tft.setTextSize(1);

  tft.println(F("WaveShare 1.8\" ST7735S"));

  tft.setTextColor(C_YEL);

  tft.println(F("SPI demo (Adafruit GFX)"));

  tft.setTextColor(C_TXT);

  tft.println();

  tft.setTextSize(1);

  tft.print(F("Resolution: "));

  tft.print(tft.width());

  tft.print('x');

  tft.println(tft.height());

  tft.setTextColor(C_MAG);

  tft.println(F("Draw test..."));

  delay(900);

}

void gradientBars() {

  // Simple color sweep

  for (int x = 0; x < tft.width(); x++) {

    uint8_t r = map(x, 0, tft.width()-1, 0, 255);

    uint16_t color = tft.color565(r, 50, 255 - r);

    tft.drawFastVLine(x, 0, tft.height(), color);

  }

  delay(600);

}

void setup() {

  // Optional BL control:

  // pinMode(TFT_BL, OUTPUT);

  // analogWrite(TFT_BL, backlight);

  // Initialize display

  tft.initR(INITR_BLACKTAB);  // try INITR_GREENTAB if colors look wrong

  tft.setRotation(1);         // 1 = landscape (160x128). Use 0 for portrait (128x160)

  // Clear and greet

  tft.fillScreen(C_BG);

  tft.setTextWrap(false);

  tft.setTextSize(1);

  tft.setTextColor(C_TXT);

  // Quick “hello” banner

  tft.fillRect(0, 0, tft.width(), 14, C_ACC);

  tft.setCursor(4, 3);

  tft.setTextColor(C_BG);

  tft.print(F("WaveShare 1.8\" ST7735S"));

  delay(400);

  demoPrimitives();

  demoText();

  gradientBars();

  // Tiny FPS-ish fill test

  uint32_t t0 = millis();

  for (int i=0; i<50; i++) {

    uint16_t color = tft.color565(random(255), random(255), random(255));

    int x = random(tft.width()-30);

    int y = random(tft.height()-20);

    tft.fillRect(x, y, 30, 20, color);

  }

  uint32_t t1 = millis();

  tft.fillScreen(C_BG);

  tft.setCursor(2, 2);

  tft.setTextColor(C_TXT);

  tft.setTextSize(1);

  tft.println(F("Random fill test:"));

  tft.print(F("Time: "));

  tft.print(t1 - t0);

  tft.println(F(" ms"));

  tft.println(F("(Lower is faster)"));

}

void loop() {

  // Simple loop animation: moving bar

  static int x = 0;

  static int dx = 3;

  // Clear a narrow strip

  tft.fillRect(0, tft.height()-16, tft.width(), 16, C_BG);

  // Draw bar

  tft.fillRect(x, tft.height()-14, 32, 12, C_YEL);

  x += dx;

  if (x < 0 || x + 32 > tft.width()) dx = -dx;

  delay(30);

}