#include  <gui/gui.h>      // GUI (screen/keyboard) API

#include  "images.h"

//----------------------------------------------------------------------------- ----------------------------------------
static Canvas*         _canvas;
static uint8_t         _tlx;
static uint8_t         _tly;

static uint8_t         _x;
static uint8_t         _y;

static const image_t*  _img;

static bool            _blk;
static Color           _set;
static Color           _clr;

//+============================================================================
static
void  _showByteSet (const uint8_t b)
{
	for (uint8_t m = 0x80;  m;  m >>= 1) {
		if (b & m)  // plot only SET bits
			canvas_draw_dot(_canvas, (_tlx +_x), (_tly +_y)) ;
		if ( ((++_x) == _img->w) && !(_x = 0) && ((++_y) == _img->h) )  break ;
	}
}

//+============================================================================
static
void  _showByteClr (const uint8_t b)
{
	for (uint8_t m = 0x80;  m;  m >>= 1) {
		if (!(b & m))  // plot only CLR bits
			canvas_draw_dot(_canvas, (_tlx +_x), (_tly +_y)) ;
		if ( ((++_x) == _img->w) && !(_x = 0) && ((++_y) == _img->h) )  break ;
	}
}

//+============================================================================
static
void  _showByteAll (const uint8_t b)
{
	for (uint8_t m = 0x80;  m;  m >>= 1) {
		if ((!!(b & m)) ^ _blk) { // Change colour only when required
			canvas_set_color(_canvas, ((b & m) ? _set : _clr));
			_blk = !_blk;
		}
		canvas_draw_dot(_canvas, (_tlx +_x), (_tly +_y)) ;
		if ( ((++_x) == _img->w) && !(_x = 0) && ((++_y) == _img->h) )  break ;
	}
}

//+============================================================================
// available modes are SHOW_SET_BLK - plot image pixels that are  SET in BLACK
//                     SHOW_XOR     - same as SET_BLACK
//                     SHOW_SET_WHT - plot image pixels that are  SET in WHITE
//                     SHOW_CLR_BLK - plot image pixels that are CLEAR in BLACK
//                     SHOW_CLR_WHT - plot image pixels that are CLEAR in WHITE
//                     SHOW_ALL     - plot all images pixels as they are
//                     SHOW_ALL_INV - plot all images pixels inverted
//
void  show (Canvas* const  canvas,  const uint8_t tlx,  const uint8_t tly,
            const image_t* img,     const showMode_t mode)
{
	void(*fnShow)(const uint8_t) = NULL;

	const uint8_t*  bp = img->data;

	// code size optimisation
	switch (mode & SHOW_INV_) {
		case SHOW_NRM_:
			_set = ColorBlack;
			_clr = ColorWhite;
			break;

		case SHOW_INV_:
			_set = ColorWhite;
			_clr = ColorBlack;
			break;

		case SHOW_BLK_:
			canvas_set_color(canvas, ColorBlack);
			break;

		case SHOW_WHT_:
			canvas_set_color(canvas, ColorWhite);
			break;

	}
	switch (mode & SHOW_INV_) {
		case SHOW_NRM_:
		case SHOW_INV_:
			fnShow = _showByteAll;
			canvas_set_color(canvas, ColorWhite);
			_blk = 0;
			break;

		case SHOW_BLK_:
		case SHOW_WHT_:
			switch (mode & SHOW_ALL_) {
				case SHOW_SET_:
					fnShow = _showByteSet;
					break;
				case SHOW_CLR_:
					fnShow = _showByteClr;
					break;
			}
			break;
	}
	furi_check(fnShow);

	// I want nested functions!
	_canvas = canvas;
	_img    = img;
	_tlx    = tlx;
	_tly    = tly;
	_x      = 0;
	_y      = 0;

	// Compressed
	if (img->c) {
		for (unsigned int i = 0;  i < img->len;  i++, bp++) {
			// Compressed data? {tag, length, value}
			if (*bp == img->tag) {
				for (uint16_t c = 0;  c < bp[1];  c++)  fnShow(bp[2]) ;
				bp += 3 -1;
				i  += 3 -1;

			// Uncompressed byte
			} else {
				fnShow(*bp);
			}
		}

	// Not compressed
	} else {
		for (unsigned int i = 0;  i < img->len;  i++, bp++)  fnShow(*bp) ;
	}
}