// CSE 373
// University of Washington
// Routines for manipulating bitmap files
// Homework 5
// May 2000

#include <stdio.h>
#include "bmp.h"

//#include <iostream>
//using namespace std;

void out(FILE *f, unsigned char *pch) { fputc(*pch, f); }
void out2(FILE *f, unsigned char *pch) { out(f, pch++); out(f, pch); }
void out3(FILE *f, unsigned char *pch) { out(f, pch++); out2(f, pch); }
void out4(FILE *f, unsigned char *pch) { out2(f, pch); pch+=2; out2(f, pch); }


// read in bitmap data and echo header info to output file f
// reads from standard input
//    f should be an already-opened output file, e.g. "out.bmp"
//    pixels should be a 256x256 array to work with the sample files
void readbmp(FILE *f, RGBQUAD palette[palsize], unsigned char pixels[rows][cols])
{
	BITMAPFILEHEADER bmfh;
	BITMAPINFO bmi;
	int i;
	unsigned char *pch;

	// read in BITMAPFILEHEADER structure from file
	pch = (unsigned char *)&bmfh;
	scanf("%2c", pch);
	out2(f, pch);
	pch+=2; // just read 2 chars
	pch+=2; // skip 2 bytes of padding; may need to comment out this line
	for (i=0; i<12; i++) {
		scanf("%c", pch);
		out(f, pch++);
	}
	// read in BITMAPINFO structure
	pch = (unsigned char *)&bmi;
	for (i=0; i<sizeof(bmi.bmiHeader); i++) {
		scanf("%c", pch);
		out(f, pch++);
	}
	// read in palette info
	for (i=0; i<256; i++) {
		scanf("%4c", &palette[i]);
		out4(f, (unsigned char*) &palette[i]);
	}
	// read in pixel data, but don't echo it to output file
	// (we're going to change the pixels later)
	for (int r=0; r<rows; r++) {
		for (int c=0; c<cols; c++) {
			scanf("%c", &pixels[r][c]);
		}
	}
}	


// write pixel data to output file
//    (assumes header info has already been written to file)
void writebmp(FILE *f, unsigned char pixels[rows][cols])
{
	for (int r=0; r<rows; r++) {
		for (int c=0; c<cols; c++) {
			out(f, &pixels[r][c]);
		}
	}
}