/***************************************************
  Arduino TFT graphics library targeted at ESP8266
  and ESP32 based boards.

  This is a standalone library that contains the
  hardware driver, the graphics functions and the
  proportional fonts.

  The built-in fonts 4, 6, 7 and 8 are Run Length
  Encoded (RLE) to reduce the FLASH footprint.

  Last review/edit by Bodmer: 26/01/20
 ****************************************************/

// Stop fonts etc being loaded multiple times
#ifndef _TFT_eSPIH_
#define _TFT_eSPIH_

#define TFT_ESPI_VERSION "2.2.20"

/***************************************************************************************
**                         Section 1: Load required header files
***************************************************************************************/

//Standard support
#include <Arduino.h>
#include <Print.h>
#include <SPI.h>

/***************************************************************************************
**                         Section 2: Load library and processor specific header files
***************************************************************************************/
// Include header file that defines the fonts loaded, the TFT drivers
// available and the pins to be used, etc, etc
#include <User_Setup_Select.h>

// Handle FLASH based storage e.g. PROGMEM
#ifdef __AVR__
  #include <avr/pgmspace.h>
#elif defined(ESP8266) || defined(ESP32)
  #include <pgmspace.h>
#else
  #define PROGMEM
#endif

// Include the processor specific drivers
#if defined (ESP32)
  #include "Processors/TFT_eSPI_ESP32.h"
#elif defined (ESP8266)
  #include "Processors/TFT_eSPI_ESP8266.h"
#elif defined (STM32)
  #include "Processors/TFT_eSPI_STM32.h"
#else
  #include "Processors/TFT_eSPI_Generic.h"
#endif

/***************************************************************************************
**                         Section 3: Interface setup
***************************************************************************************/
#ifndef TAB_COLOUR
  #define TAB_COLOUR 0
#endif

// If the SPI frequency is not defined, set a default
#ifndef SPI_FREQUENCY
  #define SPI_FREQUENCY  20000000
#endif

// If the SPI read frequency is not defined, set a default
#ifndef SPI_READ_FREQUENCY
  #define SPI_READ_FREQUENCY 10000000
#endif

// Some ST7789 boards do not work with Mode 0
#if defined(ST7789_DRIVER) || defined(ST7789_2_DRIVER)
  #define TFT_SPI_MODE SPI_MODE3
#else
  #define TFT_SPI_MODE SPI_MODE0
#endif

// If the XPT2046 SPI frequency is not defined, set a default
#ifndef SPI_TOUCH_FREQUENCY
  #define SPI_TOUCH_FREQUENCY  2500000
#endif

/***************************************************************************************
**                         Section 4: Setup fonts
***************************************************************************************/
// Use GLCD font in error case where user requests a smooth font file
// that does not exist (this is a temporary fix to stop ESP32 reboot)
#ifdef SMOOTH_FONT
  #ifndef LOAD_GLCD
    #define LOAD_GLCD
  #endif
#endif

// Only load the fonts defined in User_Setup.h (to save space)
// Set flag so RLE rendering code is optionally compiled
#ifdef LOAD_GLCD
  #include <Fonts/glcdfont.c>
#endif

#ifdef LOAD_FONT2
  #include <Fonts/Font16.h>
#endif

#ifdef LOAD_FONT4
  #include <Fonts/Font32rle.h>
  #define LOAD_RLE
#endif

#ifdef LOAD_FONT6
  #include <Fonts/Font64rle.h>
  #ifndef LOAD_RLE
    #define LOAD_RLE
  #endif
#endif

#ifdef LOAD_FONT7
  #include <Fonts/Font7srle.h>
  #ifndef LOAD_RLE
    #define LOAD_RLE
  #endif
#endif

#ifdef LOAD_FONT8
  #include <Fonts/Font72rle.h>
  #ifndef LOAD_RLE
    #define LOAD_RLE
  #endif
#elif defined LOAD_FONT8N // Optional narrower version
  #define LOAD_FONT8
  #include <Fonts/Font72x53rle.h>
  #ifndef LOAD_RLE
    #define LOAD_RLE
  #endif
#endif

#ifdef LOAD_GFXFF
  // We can include all the free fonts and they will only be built into
  // the sketch if they are used
  #include <Fonts/GFXFF/gfxfont.h>
  // Call up any user custom fonts
  #include <User_Setups/User_Custom_Fonts.h>
#endif // #ifdef LOAD_GFXFF

// Create a null default font in case some fonts not used (to prevent crash)
const  uint8_t widtbl_null[1] = {0};
PROGMEM const uint8_t chr_null[1] = {0};
PROGMEM const uint8_t* const chrtbl_null[1] = {chr_null};

// This is a structure to conveniently hold information on the default fonts
// Stores pointer to font character image address table, width table and height
typedef struct {
    const uint8_t *chartbl;
    const uint8_t *widthtbl;
    uint8_t height;
    uint8_t baseline;
    } fontinfo;

// Now fill the structure
const PROGMEM fontinfo fontdata [] = {
  #ifdef LOAD_GLCD
   { (const uint8_t *)font, widtbl_null, 0, 0 },
  #else
   { (const uint8_t *)chrtbl_null, widtbl_null, 0, 0 },
  #endif
   // GLCD font (Font 1) does not have all parameters
   { (const uint8_t *)chrtbl_null, widtbl_null, 8, 7 },

  #ifdef LOAD_FONT2
   { (const uint8_t *)chrtbl_f16, widtbl_f16, chr_hgt_f16, baseline_f16},
  #else
   { (const uint8_t *)chrtbl_null, widtbl_null, 0, 0 },
  #endif

   // Font 3 current unused
   { (const uint8_t *)chrtbl_null, widtbl_null, 0, 0 },

  #ifdef LOAD_FONT4
   { (const uint8_t *)chrtbl_f32, widtbl_f32, chr_hgt_f32, baseline_f32},
  #else
   { (const uint8_t *)chrtbl_null, widtbl_null, 0, 0 },
  #endif

   // Font 5 current unused
   { (const uint8_t *)chrtbl_null, widtbl_null, 0, 0 },

  #ifdef LOAD_FONT6
   { (const uint8_t *)chrtbl_f64, widtbl_f64, chr_hgt_f64, baseline_f64},
  #else
   { (const uint8_t *)chrtbl_null, widtbl_null, 0, 0 },
  #endif

  #ifdef LOAD_FONT7
   { (const uint8_t *)chrtbl_f7s, widtbl_f7s, chr_hgt_f7s, baseline_f7s},
  #else
   { (const uint8_t *)chrtbl_null, widtbl_null, 0, 0 },
  #endif

  #ifdef LOAD_FONT8
   { (const uint8_t *)chrtbl_f72, widtbl_f72, chr_hgt_f72, baseline_f72}
  #else
   { (const uint8_t *)chrtbl_null, widtbl_null, 0, 0 }
  #endif
};

/***************************************************************************************
**                         Section 5: Font datum enumeration
***************************************************************************************/
//These enumerate the text plotting alignment (reference datum point)
#define TL_DATUM 0 // Top left (default)
#define TC_DATUM 1 // Top centre
#define TR_DATUM 2 // Top right
#define ML_DATUM 3 // Middle left
#define CL_DATUM 3 // Centre left, same as above
#define MC_DATUM 4 // Middle centre
#define CC_DATUM 4 // Centre centre, same as above
#define MR_DATUM 5 // Middle right
#define CR_DATUM 5 // Centre right, same as above
#define BL_DATUM 6 // Bottom left
#define BC_DATUM 7 // Bottom centre
#define BR_DATUM 8 // Bottom right
#define L_BASELINE  9 // Left character baseline (Line the 'A' character would sit on)
#define C_BASELINE 10 // Centre character baseline
#define R_BASELINE 11 // Right character baseline

/***************************************************************************************
**                         Section 6: Colour enumeration
***************************************************************************************/
// Default color definitions
#define TFT_BLACK       0x0000      /*   0,   0,   0 */
#define TFT_NAVY        0x000F      /*   0,   0, 128 */
#define TFT_DARKGREEN   0x03E0      /*   0, 128,   0 */
#define TFT_DARKCYAN    0x03EF      /*   0, 128, 128 */
#define TFT_MAROON      0x7800      /* 128,   0,   0 */
#define TFT_PURPLE      0x780F      /* 128,   0, 128 */
#define TFT_OLIVE       0x7BE0      /* 128, 128,   0 */
#define TFT_LIGHTGREY   0xD69A      /* 211, 211, 211 */
#define TFT_DARKGREY    0x7BEF      /* 128, 128, 128 */
#define TFT_BLUE        0x001F      /*   0,   0, 255 */
#define TFT_GREEN       0x07E0      /*   0, 255,   0 */
#define TFT_CYAN        0x07FF      /*   0, 255, 255 */
#define TFT_RED         0xF800      /* 255,   0,   0 */
#define TFT_MAGENTA     0xF81F      /* 255,   0, 255 */
#define TFT_YELLOW      0xFFE0      /* 255, 255,   0 */
#define TFT_WHITE       0xFFFF      /* 255, 255, 255 */
#define TFT_ORANGE      0xFDA0      /* 255, 180,   0 */
#define TFT_GREENYELLOW 0xB7E0      /* 180, 255,   0 */
#define TFT_PINK        0xFE19      /* 255, 192, 203 */ //Lighter pink, was 0xFC9F      
#define TFT_BROWN       0x9A60      /* 150,  75,   0 */
#define TFT_GOLD        0xFEA0      /* 255, 215,   0 */
#define TFT_SILVER      0xC618      /* 192, 192, 192 */
#define TFT_SKYBLUE     0x867D      /* 135, 206, 235 */
#define TFT_VIOLET      0x915C      /* 180,  46, 226 */

// Next is a special 16 bit colour value that encodes to 8 bits
// and will then decode back to the same 16 bit value.
// Convenient for 8 bit and 16 bit transparent sprites.
#define TFT_TRANSPARENT 0x0120 // This is actually a dark green

// Default palette for 4 bit colour sprites
static const uint16_t default_4bit_palette[] PROGMEM = {
  TFT_BLACK,    //  0  ^
  TFT_BROWN,    //  1  |
  TFT_RED,      //  2  |
  TFT_ORANGE,   //  3  |
  TFT_YELLOW,   //  4  Colours 0-9 follow the resistor colour code!
  TFT_GREEN,    //  5  |
  TFT_BLUE,     //  6  |
  TFT_PURPLE,   //  7  |
  TFT_DARKGREY, //  8  |
  TFT_WHITE,    //  9  v
  TFT_CYAN,     // 10  Blue+green mix
  TFT_MAGENTA,  // 11  Blue+red mix
  TFT_MAROON,   // 12  Darker red colour
  TFT_DARKGREEN,// 13  Darker green colour
  TFT_NAVY,     // 14  Darker blue colour
  TFT_PINK      // 15
};

/***************************************************************************************
**                         Section 7: Diagnostic support
***************************************************************************************/
// #define TFT_eSPI_DEBUG     // Switch on debug support serial messages  (not used yet)
// #define TFT_eSPI_FNx_DEBUG // Switch on debug support for function "x" (not used yet)

// This structure allows sketches to retrieve the user setup parameters at runtime
// by calling getSetup(), zero impact on code size unless used, mainly for diagnostics
typedef struct
{
String  version = TFT_ESPI_VERSION;
int32_t esp;         // Processor code
uint8_t trans;       // SPI transaction supoort
uint8_t serial;      // Serial (SPI) or parallel
uint8_t overlap;     // ESP8266 overlap mode

#if defined (ESP32)  // TODO: make generic for other processors
  #if defined (USE_HSPI_PORT)
    uint8_t  port = HSPI;
  #else
    uint8_t  port = VSPI;
  #endif
#endif

uint16_t tft_driver; // Hexadecimal code
uint16_t tft_width;  // Rotation 0 width and height
uint16_t tft_height;

uint8_t r0_x_offset; // Display offsets, not all used yet
uint8_t r0_y_offset;
uint8_t r1_x_offset;
uint8_t r1_y_offset;
uint8_t r2_x_offset;
uint8_t r2_y_offset;
uint8_t r3_x_offset;
uint8_t r3_y_offset;

int8_t pin_tft_mosi; // SPI pins
int8_t pin_tft_miso;
int8_t pin_tft_clk;
int8_t pin_tft_cs;

int8_t pin_tft_dc;   // Control pins
int8_t pin_tft_rd;
int8_t pin_tft_wr;
int8_t pin_tft_rst;

int8_t pin_tft_d0;   // Parallel port pins
int8_t pin_tft_d1;
int8_t pin_tft_d2;
int8_t pin_tft_d3;
int8_t pin_tft_d4;
int8_t pin_tft_d5;
int8_t pin_tft_d6;
int8_t pin_tft_d7;

int8_t pin_tft_led;
int8_t pin_tft_led_on;

int8_t pin_tch_cs;   // Touch chip select pin

int16_t tft_spi_freq;// TFT write SPI frequency
int16_t tft_rd_freq; // TFT read  SPI frequency
int16_t tch_spi_freq;// Touch controller read/write SPI frequency
} setup_t;

/***************************************************************************************
**                         Section 8: Class member and support functions
***************************************************************************************/
// Swap any type
template <typename T> static inline void
swap_coord(T& a, T& b) { T t = a; a = b; b = t; }

// Callback prototype for smooth font pixel colour read
typedef uint16_t (*getColorCallback)(uint16_t x, uint16_t y);

// Class functions and variables
class TFT_eSPI : public Print {

 //--------------------------------------- public ------------------------------------//
 public:

  TFT_eSPI(int16_t _W = TFT_WIDTH, int16_t _H = TFT_HEIGHT);

  // init() and begin() are equivalent, begin() included for backwards compatibility
  // Sketch defined tab colour option is for ST7735 displays only
  void     init(uint8_t tc = TAB_COLOUR), begin(uint8_t tc = TAB_COLOUR);

  // These are virtual so the TFT_eSprite class can override them with sprite specific functions
  virtual void     drawPixel(int32_t x, int32_t y, uint32_t color),
                   drawChar(int32_t x, int32_t y, uint16_t c, uint32_t color, uint32_t bg, uint8_t size),
                   drawLine(int32_t xs, int32_t ys, int32_t xe, int32_t ye, uint32_t color),
                   drawFastVLine(int32_t x, int32_t y, int32_t h, uint32_t color),
                   drawFastHLine(int32_t x, int32_t y, int32_t w, uint32_t color),
                   fillRect(int32_t x, int32_t y, int32_t w, int32_t h, uint32_t color);

  virtual int16_t  drawChar(uint16_t uniCode, int32_t x, int32_t y, uint8_t font),
                   drawChar(uint16_t uniCode, int32_t x, int32_t y),
                   height(void),
                   width(void);

  void     setRotation(uint8_t r); // Set the display image orientation to 0, 1, 2 or 3
  uint8_t  getRotation(void);      // Read the current rotation

  void     invertDisplay(bool i);  // Tell TFT to invert all displayed colours


  // The TFT_eSprite class inherits the following functions (not all are useful to Sprite class
  void     setAddrWindow(int32_t xs, int32_t ys, int32_t w, int32_t h), // Note: start coordinates + width and height
           setWindow(int32_t xs, int32_t ys, int32_t xe, int32_t ye);   // Note: start + end coordinates

  // Push (aka write pixel) colours to the TFT (use setAddrWindow() first)
  void     pushColor(uint16_t color),
           pushColor(uint16_t color, uint32_t len),  // Deprecated, use pushBlock()
           pushColors(uint16_t  *data, uint32_t len, bool swap = true), // With byte swap option
           pushColors(uint8_t  *data, uint32_t len); // Deprecated, use pushPixels()

           // Write a solid block of a single colour
  void     pushBlock(uint16_t color, uint32_t len);

           // Write a set of pixels stored in memory, use setSwapBytes(true/false) function to correct endianess
  void     pushPixels(const void * data_in, uint32_t len);

           // Read the colour of a pixel at x,y and return value in 565 format 
  uint16_t readPixel(int32_t x, int32_t y);

           // Support for half duplex (bi-directional SDA) SPI bus where MOSI must be switched to input
           #ifdef TFT_SDA_READ
             #if defined (TFT_eSPI_ENABLE_8_BIT_READ)
  uint8_t  tft_Read_8(void);     // Read 8 bit value from TFT command register
             #endif
  void     begin_SDA_Read(void); // Begin a read on a half duplex (bi-directional SDA) SPI bus - sets MOSI to input
  void     end_SDA_Read(void);   // Restore MOSI to output
           #endif

  // Graphics drawing
  void     fillScreen(uint32_t color),
           drawRect(int32_t x, int32_t y, int32_t w, int32_t h, uint32_t color),
           drawRoundRect(int32_t x, int32_t y, int32_t w, int32_t h, int32_t radius, uint32_t color),
           fillRoundRect(int32_t x, int32_t y, int32_t w, int32_t h, int32_t radius, uint32_t color);


  void     drawCircle(int32_t x, int32_t y, int32_t r, uint32_t color),
           drawCircleHelper(int32_t x, int32_t y, int32_t r, uint8_t cornername, uint32_t color),
           fillCircle(int32_t x, int32_t y, int32_t r, uint32_t color),
           fillCircleHelper(int32_t x, int32_t y, int32_t r, uint8_t cornername, int32_t delta, uint32_t color),

           drawEllipse(int16_t x, int16_t y, int32_t rx, int32_t ry, uint16_t color),
           fillEllipse(int16_t x, int16_t y, int32_t rx, int32_t ry, uint16_t color),

           //                 Corner 1               Corner 2               Corner 3
           drawTriangle(int32_t x1,int32_t y1, int32_t x2,int32_t y2, int32_t x3,int32_t y3, uint32_t color),
           fillTriangle(int32_t x1,int32_t y1, int32_t x2,int32_t y2, int32_t x3,int32_t y3, uint32_t color);

  // Image rendering
           // Swap the byte order for pushImage() and pushPixels() - corrects endianness
  void     setSwapBytes(bool swap);
  bool     getSwapBytes(void);

           // Draw bitmap
  void     drawBitmap( int16_t x, int16_t y, const uint8_t *bitmap, int16_t w, int16_t h, uint16_t fgcolor),
           drawBitmap( int16_t x, int16_t y, const uint8_t *bitmap, int16_t w, int16_t h, uint16_t fgcolor, uint16_t bgcolor),
           drawXBitmap(int16_t x, int16_t y, const uint8_t *bitmap, int16_t w, int16_t h, uint16_t fgcolor),
           drawXBitmap(int16_t x, int16_t y, const uint8_t *bitmap, int16_t w, int16_t h, uint16_t fgcolor, uint16_t bgcolor),
           setBitmapColor(uint16_t fgcolor, uint16_t bgcolor); // Define the 2 colours for 1bpp sprites

           // Set TFT pivot point (use when rendering rotated sprites)
  void     setPivot(int16_t x, int16_t y);
  int16_t  getPivotX(void), // Get pivot x
           getPivotY(void); // Get pivot y

           // The next functions can be used as a pair to copy screen blocks (or horizontal/vertical lines) to another location
           // Read a block of pixels to a data buffer, buffer is 16 bit and the size must be at least w * h
  void     readRect(int32_t x, int32_t y, int32_t w, int32_t h, uint16_t *data);
           // Write a block of pixels to the screen which have been read by readRect()
  void     pushRect(int32_t x, int32_t y, int32_t w, int32_t h, uint16_t *data);

           // These are used to render images or sprites stored in RAM arrays (used by Sprite class for 16bpp Sprites)
  void     pushImage(int32_t x, int32_t y, int32_t w, int32_t h, uint16_t *data);
  void     pushImage(int32_t x, int32_t y, int32_t w, int32_t h, uint16_t *data, uint16_t transparent);

           // These are used to render images stored in FLASH (PROGMEM)
  void     pushImage(int32_t x, int32_t y, int32_t w, int32_t h, const uint16_t *data, uint16_t transparent);
  void     pushImage(int32_t x, int32_t y, int32_t w, int32_t h, const uint16_t *data);

           // These are used by Sprite class pushSprite() member function for 1, 4 and 8 bits per pixel (bpp) colours
           // They are not intended to be used with user sketches (but could be)
           // Set bpp8 true for 8bpp sprites, false otherwise. The cmap pointer must be specified for 4bpp
  void     pushImage(int32_t x, int32_t y, int32_t w, int32_t h, uint8_t  *data, bool bpp8 = true, uint16_t *cmap = nullptr);
  void     pushImage(int32_t x, int32_t y, int32_t w, int32_t h, uint8_t  *data, uint8_t  transparent, bool bpp8 = true, uint16_t *cmap = nullptr);

           // This next function has been used successfully to dump the TFT screen to a PC for documentation purposes
           // It reads a screen area and returns the 3 RGB 8 bit colour values of each pixel in the buffer
           // Set w and h to 1 to read 1 pixel's colour. The data buffer must be at least w * h * 3 bytes
  void     readRectRGB(int32_t x, int32_t y, int32_t w, int32_t h, uint8_t *data);

  // Text rendering - value returned is the pixel width of the rendered text
  int16_t  drawNumber(long intNumber, int32_t x, int32_t y, uint8_t font), // Draw integer using specified font number
           drawNumber(long intNumber, int32_t x, int32_t y),               // Draw integer using current font
           
           // Decimal is the number of decimal places to render
           // Use with setTextDatum() to position values on TFT, and setTextPadding() to blank old displayed values
           drawFloat(float floatNumber, uint8_t decimal, int32_t x, int32_t y, uint8_t font), // Draw float using specified font number
           drawFloat(float floatNumber, uint8_t decimal, int32_t x, int32_t y),               // Draw float using current font

           // Handle char arrays
           // Use with setTextDatum() to position string on TFT, and setTextPadding() to blank old displayed strings
           drawString(const char *string, int32_t x, int32_t y, uint8_t font),  // Draw string using specifed font number
           drawString(const char *string, int32_t x, int32_t y),                // Draw string using current font
           drawString(const String& string, int32_t x, int32_t y, uint8_t font),// Draw string using specifed font number
           drawString(const String& string, int32_t x, int32_t y),              // Draw string using current font

           drawCentreString(const char *string, int32_t x, int32_t y, uint8_t font),  // Deprecated, use setTextDatum() and drawString()
           drawRightString(const char *string, int32_t x, int32_t y, uint8_t font),   // Deprecated, use setTextDatum() and drawString()
           drawCentreString(const String& string, int32_t x, int32_t y, uint8_t font),// Deprecated, use setTextDatum() and drawString()
           drawRightString(const String& string, int32_t x, int32_t y, uint8_t font); // Deprecated, use setTextDatum() and drawString()

  // Text rendering and font handling support funtions
  void     setCursor(int16_t x, int16_t y),                 // Set cursor for tft.print()
           setCursor(int16_t x, int16_t y, uint8_t font);   // Set cursor and font number for tft.print()

  int16_t  getCursorX(void),                                // Read current cursor x position (moves with tft.print())
           getCursorY(void);                                // Read current cursor y position
           
  void     setTextColor(uint16_t color),                    // Set character (glyph) color only (background not over-written)
           setTextColor(uint16_t fgcolor, uint16_t bgcolor),// Set character (glyph) foreground and backgorund colour
           setTextSize(uint8_t size);                       // Set character size multiplier (this increases pixel size)

  void     setTextWrap(bool wrapX, bool wrapY = false);     // Turn on/off wrapping of text in TFT width and/or height

  void     setTextDatum(uint8_t datum);                     // Set text datum position (default is top left), see Section 6 above 
  uint8_t  getTextDatum(void);

  void     setTextPadding(uint16_t x_width);                // Set text padding (background blanking/over-write) width in pixels
  uint16_t getTextPadding(void);                            // Get text padding

#ifdef LOAD_GFXFF
  void     setFreeFont(const GFXfont *f = NULL),            // Select the GFX Free Font
           setTextFont(uint8_t font);                       // Set the font number to use in future
#else
  void     setFreeFont(uint8_t font),                       // Not used, historical fix to prevent an error
           setTextFont(uint8_t font);                       // Set the font number to use in future
#endif

  int16_t  textWidth(const char *string, uint8_t font),     // Returns pixel width of string in specified font
           textWidth(const char *string),                   // Returns pixel width of string in current font
           textWidth(const String& string, uint8_t font),   // As above for String types
           textWidth(const String& string),
           fontHeight(int16_t font),                        // Returns pixel height of string in specified font
           fontHeight(void);                                // Returns pixel width of string in current font

           // Used by library and Smooth font class to extract Unicode point codes from a UTF8 encoded string
  uint16_t decodeUTF8(uint8_t *buf, uint16_t *index, uint16_t remaining),
           decodeUTF8(uint8_t c);

           // Support function to UTF8 decode and draw characters piped through print stream
  size_t   write(uint8_t);
  
           // Used by Smooth font class to fetch a pixel colour for the anti-aliasing
  void     setCallback(getColorCallback getCol);

  uint16_t fontsLoaded(void); // Each bit in returned value represents a font type that is loaded - used for debug/error handling only

  // Low level read/write
  void     spiwrite(uint8_t);        // legacy support only

  void     writecommand(uint8_t c),  // Send a command, function resets DC/RS high ready for data
           writedata(uint8_t d);     // Send data with DC/RS set high

  void     commandList(const uint8_t *addr); // Send a initialisation sequence to TFT stored in FLASH

  uint8_t  readcommand8( uint8_t cmd_function, uint8_t index = 0); // read 8 bits from TFT
  uint16_t readcommand16(uint8_t cmd_function, uint8_t index = 0); // read 16 bits from TFT
  uint32_t readcommand32(uint8_t cmd_function, uint8_t index = 0); // read 32 bits from TFT


  // Colour conversion
           // Convert 8 bit red, green and blue to 16 bits
  uint16_t color565(uint8_t red, uint8_t green, uint8_t blue);

           // Convert 8 bit colour to 16 bits
  uint16_t color8to16(uint8_t color332);
           // Convert 16 bit colour to 8 bits
  uint8_t  color16to8(uint16_t color565);

           // Convert 16 bit colour to/from 24 bit, R+G+B concatenated into LS 24 bits
  uint32_t color16to24(uint16_t color565);
  uint32_t color24to16(uint32_t color888);

           // Alpha blend 2 colours, see generic "alphaBlend_Test" example
           // alpha =   0 = 100% background colour
           // alpha = 255 = 100% foreground colour
  uint16_t alphaBlend(uint8_t alpha, uint16_t fgc, uint16_t bgc);
           // 16 bit colour alphaBlend with alpha dither (dither reduces colour banding)
  uint16_t alphaBlend(uint8_t alpha, uint16_t fgc, uint16_t bgc, uint8_t dither);
           // 24 bit colour alphaBlend with optional alpha dither
  uint32_t alphaBlend24(uint8_t alpha, uint32_t fgc, uint32_t bgc, uint8_t dither = 0);


  // DMA support functions - these are currently just for SPI writes whe using the STM32 processors
           // Bear in mind DMA will only be of benefit in particular circumstances and can be tricky
           // to manage by noobs. The functions have however been designed to be noob friendly and
           // avoid a few DMA behaviour "gotchas".
           //
           // At best you will get a 2x TFT rendering performance improvement when using DMA because
           // this library handles the SPI bus so efficiently during normal (non DMA) transfers. The best
           // performance improvement scenario is the DMA transfer time is exactly the same as the time it
           // takes for the processor to prepare the next image buffer and initiate another DMA transfer.
           //
           // DMA transfer to the TFT is done while the processor moves on to handle other tasks. Bear
           // this in mind and watch out for "gotchas" like the image buffer going out of scope as the
           // processor leaves a function or its content being changed while the DMA engine is reading it.
           //
           // The compiler MAY change the implied scope of a buffer which has been set aside by creating
           // and an array. For example a buffer defined before a "for-next" loop may get de-allocated when
           // the loop ends. To avoid this use, for example, malloc() and free() to take control of when
           // the buffer space is available and ensure it is not released until DMA is complete.
           //
           // Clearly you should not modify a buffer that is being DMA'ed to the TFT until the DMA is over.
           // Use the dmaBusy() function to check this.  Use tft.startWrite() before invoking DMA so the
           // TFT chip select stays low. If you use tft.endWrite() before DMA is complete then the endWrite
           // function will wait for the DMA to complete, so this may defeat any DMA performance benefit.
           //

  bool     initDMA(void);     // Initialise the DMA engine and attach to SPI bus - typically used in setup()
  void     deInitDMA(void);   // De-initialise the DMA engine and detach from SPI bus - typically not used
  
           // Push an image to the TFT using DMA, buffer is optional and grabs (double buffers) a copy of the image
           // Use the buffer if the image data will get over-written or destroyed while DMA is in progress
           // If swapping colour bytes is defined, and the double buffer option is NOT used then the bytes
           // in the original data image will be swapped by the function before DMA is initiated.
           // The function will wait for the last DMA to complete if it is called while a previous DMA is still
           // in progress, this simplifies the sketch and helps avoid "gotchas".
  void     pushImageDMA(int32_t x, int32_t y, int32_t w, int32_t h, uint16_t* data, uint16_t* buffer = nullptr);

           // Push a block of pixels into a window set up using setAddrWindow()
  void     pushPixelsDMA(uint16_t* image, uint32_t len);

           // Check if the DMA is complete - use while(tft.dmaBusy); for a blocking wait
  bool     dmaBusy(void); // returns true if DMA is still in progress
  void     dmaWait(void); // wait until DMA is complete

  bool     DMA_Enabled = false;   // Flag for DMA enabled state
  uint8_t  spiBusyCheck = 0;      // Number of ESP32 transfer buffers to check

  // Bare metal functions
  void     startWrite(void);                         // Begin SPI transaction
  void     writeColor(uint16_t color, uint32_t len); // Deprecated, use pushBlock()
  void     endWrite(void);                           // End SPI transaction

  // Set/get an arbitrary library configuration attribute or option
  //       Use to switch ON/OFF capabilities such as UTF8 decoding - each attribute has a unique ID
  //       id = 0: reserved - may be used in fuuture to reset all attributes to a default state
  //       id = 1: Turn on (a=true) or off (a=false) GLCD cp437 font character error correction
  //       id = 2: Turn on (a=true) or off (a=false) UTF8 decoding
  //       id = 3: Enable or disable use of ESP32 PSRAM (if available)
           #define CP437_SWITCH 1
           #define UTF8_SWITCH  2
           #define PSRAM_ENABLE 3
  void     setAttribute(uint8_t id = 0, uint8_t a = 0); // Set attribute value
  uint8_t  getAttribute(uint8_t id = 0);                // Get attribute value

           // Used for diagnostic sketch to see library setup adopted by compiler, see Section 7 above
  void     getSetup(setup_t& tft_settings); // Sketch provides the instance to populate

  // Global variables
  static   SPIClass& getSPIinstance(void); // Get SPI class handle

  int32_t  cursor_x, cursor_y, padX;       // Text cursor x,y and padding setting
  uint32_t textcolor, textbgcolor;         // Text foreground and background colours

  uint32_t bitmap_fg, bitmap_bg;           // Bitmap foreground (bit=1) and background (bit=0) colours

  uint8_t  textfont,  // Current selected font number
           textsize,  // Current font size multiplier
           textdatum, // Text reference datum
           rotation;  // Display rotation (0-3)

  int16_t  _xpivot;   // TFT x pivot point coordinate for rotated Sprites
  int16_t  _ypivot;   // TFT x pivot point coordinate for rotated Sprites

  uint8_t  decoderState = 0;   // UTF8 decoder state        - not for user access
  uint16_t decoderBuffer;      // Unicode code-point buffer - not for user access

 //--------------------------------------- private ------------------------------------//
 private:
           // Legacy begin and end prototypes - deprecated TODO: delete
  void     spi_begin();
  void     spi_end();

  void     spi_begin_read();
  void     spi_end_read();

           // New begin and end prototypes
           // begin/end a TFT write transaction
           // For SPI bus the transmit clock rate is set
  inline void begin_tft_write()      __attribute__((always_inline));
  inline void end_tft_write()        __attribute__((always_inline));

           // begin/end a TFT read transaction
           // For SPI bus: begin lowers SPI clock rate, end reinstates transmit clock rate
  inline void begin_tft_read() __attribute__((always_inline));
  inline void end_tft_read()   __attribute__((always_inline));

           // Temporary  library development function  TODO: remove need for this
  void     pushSwapBytePixels(const void* data_in, uint32_t len);

           // Same as setAddrWindow but exits with CGRAM in read mode
  void     readAddrWindow(int32_t xs, int32_t ys, int32_t w, int32_t h);

           // Byte read prototype
  uint8_t  readByte(void);

           // GPIO parallel bus input/output direction control
  void     busDir(uint32_t mask, uint8_t mode);

           // Single GPIO input/output direction control
  void     gpioMode(uint8_t gpio, uint8_t mode);

           // Display variant settings
  uint8_t  tabcolor,                   // ST7735 screen protector "tab" colour (now invalid)
           colstart = 0, rowstart = 0; // Screen display area to CGRAM area coordinate offsets

           // Port and pin masks for control signals (ESP826 only) - TODO: remove need for this
  volatile uint32_t *dcport, *csport;
  uint32_t cspinmask, dcpinmask, wrpinmask, sclkpinmask;

           #if defined(ESP32_PARALLEL)
           // Bit masks for ESP32 parallel bus interface
  uint32_t xclr_mask, xdir_mask; // Port set/clear and direction control masks

           // Lookup table for ESP32 parallel bus interface uses 1kbyte RAM,
  uint32_t xset_mask[256]; // Makes Sprite rendering test 33% faster, for slower macro equivalent
                           // see commented out #define set_mask(C) within TFT_eSPI_ESP32.h
           #endif

  //uint32_t lastColor = 0xFFFF; // Last colour - used to minimise bit shifting overhead

  getColorCallback getColor = nullptr; // Smooth font callback function pointer

 //-------------------------------------- protected ----------------------------------//
 protected:

  //int32_t  win_xe, win_ye;          // Window end coords - not needed

  int32_t  _init_width, _init_height; // Display w/h as input, used by setRotation()
  int32_t  _width, _height;           // Display w/h as modified by current rotation
  int32_t  addr_row, addr_col;        // Window position - used to minimise window commands

  uint32_t fontsloaded;               // Bit field of fonts loaded

  uint8_t  glyph_ab,   // Smooth font glyph delta Y (height) above baseline
           glyph_bb;   // Smooth font glyph delta Y (height) below baseline

  bool     isDigits;   // adjust bounding box for numbers to reduce visual jiggling
  bool     textwrapX, textwrapY;  // If set, 'wrap' text at right and optionally bottom edge of display
  bool     _swapBytes; // Swap the byte order for TFT pushImage()
  bool     locked, inTransaction; // SPI transaction and mutex lock flags

  bool     _booted;    // init() or begin() has already run once
  
                       // User sketch manages these via set/getAttribute()
  bool     _cp437;        // If set, use correct CP437 charset (default is ON)
  bool     _utf8;         // If set, use UTF-8 decoder in print stream 'write()' function (default ON)
  bool     _psram_enable; // Enable PSRAM use for library functions (TBD) and Sprites

  uint32_t _lastColor; // Buffered value of last colour used

#ifdef LOAD_GFXFF
  GFXfont  *gfxFont;
#endif

/***************************************************************************************
**                         Section 9: TFT_eSPI class conditional extensions
***************************************************************************************/
// Load the Touch extension
#ifdef TOUCH_CS
  #include "Extensions/Touch.h"        // Loaded if TOUCH_CS is defined by user
#endif

// Load the Anti-aliased font extension
#ifdef SMOOTH_FONT
  #include "Extensions/Smooth_font.h"  // Loaded if SMOOTH_FONT is defined by user
#endif

}; // End of class TFT_eSPI

/***************************************************************************************
**                         Section 10: Additional extension classes
***************************************************************************************/
// Load the Button Class
#include "Extensions/Button.h"

// Load the Sprite Class
#include "Extensions/Sprite.h"

#endif // ends #ifndef _TFT_eSPIH_
