#include <string.h>
#include "graphics_line.h"
#include "assert.h"

#include <Adafruit_ST7735.h>
#include <Adafruit_GFX.h>
#include <SPI.h>

/* now we have an array of graphics_line */

/* remember graphics_line lines[] is the same as
    graphics_line *line, but the [] reminds us that we are passing an
    array, not a single element.
*/

#define CS   6
#define DC   7 
#define RST  8

// Colour definition
#define	BLACK           0x0000

Adafruit_ST7735 tft = Adafruit_ST7735(CS, DC, RST);

void draw_lines(int num_lines, graphics_line lines[]){
  for (int i=0; i < num_lines; i++) {
    // note how the . "dot" notation gets the field of the struct
    tft.drawLine(lines[i].xs, lines[i].ys, 
                 lines[i].xe, lines[i].ye,
                 lines[i].color);
  }
}

// creates num_lines random lines with random colors and returns pointer
// to the list containing them
graphics_line * make_random_lines(int num_lines) {
  graphics_line * list;

  // a temporary line
  graphics_line tmp;
    
  list = (typeof(list)) malloc(num_lines * sizeof(*list));

  assert(list != 0, 2);

  for (int i=0; i < num_lines; i++) {
    tmp.xs = random(0, tft.width());
    tmp.ys = random(0, tft.height());
    tmp.xe = random(0, tft.width());
    tmp.ye = random(0, tft.height());
    tmp.color = tft.Color565(random(0, 255), random(0, 255), random(0, 255));
    
    list[i] = tmp;
  }

  return list;
}
    

void setup() {
  int num_lines = 128;
  graphics_line *random_lines;
       
  Serial.begin( 9600 );
  
  // wait for button press to start
  button_pause("Press button to start");

  tft.initR(INITR_REDTAB);   // initialize a ST7735R chip, red tab

  Serial.println("Generating lines");
  random_lines = make_random_lines(num_lines);

  Serial.println("Drawing lines");
  tft.fillScreen(BLACK);
  draw_lines(num_lines, random_lines);

  Serial.println("Freeing lines");
  free(random_lines);
}


void loop() {

}