/* Taylor Carter
	10/11/2022
	Section 2
	Lab 7
	Program to print irish flag in different sizes using structures

   * intro to PPM with creating a flag of Ireland
			green|white|orange
	* reinforces loops and arrays

	PPM images have 2 parts:
		header information
		pixel information

	An image is height (rows) X width (columns).
	So, a 300 X 600 image is 300 rows high and 600 columns wide.

	All of the image contents (header and pixel info) will be written
	to stdout so when we run the program with redirection, those items
	being sent to stdout will be redirected to a file

	For example, to run this program, you will type:
		./a.out > flag.ppm
	and everything that was sent to stdout will be written to the file
	called  flag.ppm

	All the other statements that you want to go to the screen and not 
	the image will be written to stderr.

*/

#include <stdio.h>
typedef struct {
	char type[3];
	int width,height,maxColor;
}flagInfo;

typedef struct {
	unsigned int r,g,b;
}colorInfo;

int main (void){
	int  height,width,i, j, k = 0,s;  // k is used for the array
	flagInfo Header;
	colorInfo pixel;

	fprintf(stderr, "\n\nFlag of Ireland");
	fprintf(stderr, "\n\tWhat width do you want the flag to be? ");

	// 1. get the user's input for width

	scanf("%i",&width);

	// 2. calculate the height based on the proportion stated on Wikipedia

	height = width/2;
	Header = (flagInfo){"P3",width,height,255};
	fprintf(stderr, "\n\nMaking the flag with width %d & height %d ...",
		Header.width, Header.height);
	fprintf(stderr, "\n\n");

	// 3. declare an array of type:  unsigned int
	// * it will need to be big enough to hold all the color values:
	// * each pixel is made up of red, green, and blue values
	//   so each pixel has 3 things in it
	// * therefore (HINT):  the width is actually 3 times bigger

	unsigned int color[Header.height*Header.width];	


	// write to stdout the ppm header values 
	// * with redirection, these outputs will be written to the file

	fprintf(stdout, "%s\n",Header.type);
	fprintf(stdout, "%d %d %d\n",Header.width, Header.height, Header.maxColor);


	// 4. nested for loops for writing the pixel data:
	// 	a.  outer for loop is for each row
	// 	b.  because the flag of Irelad has 3 equal vertical parts,
	//        there will be 3 equal inner for loops, each one going
	//        1/3 of the way across the row (i.e. 1/3 of the columns)
	// pseudocode:
	
	for (i=0;i<height;i++) {
	   for (j=0;j<width/3;j++) {
			pixel.r=0;
			pixel.g=128;
			pixel.b=0;
			fprintf(stdout,"%u %u %u\n",pixel.r,pixel.g,pixel.b);
		}
		for (;j<(2*width)/3;j++) {
		   pixel.r=255; 
		   pixel.g=255; 
		   pixel.b=255;
			fprintf(stdout,"%u %u %u\n",pixel.r,pixel.g,pixel.b);
		}
		for (;j<width;j++) {
		   pixel.r=255;
			pixel.g=165;
			pixel.b=0;
			fprintf(stdout,"%u %u %u\n",pixel.r,pixel.g,pixel.b);
		}
	}
	
	// 5. print the contents of the array to stdout, so with redirection,
	//    the pixels will be written to the .ppm file
	//    * with P3, the unsigned int values must be written so that
	//      the values are 3 to a line (see lab write-up)
	// pseudocode:

	return 0;
}
