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

static panic(const char *reason) {
	fprintf(stderr,"\ncomptest ERROR: %s\n",reason);
	exit(1);
}

int main(int argc,char **args) {
	char cmd, ch;
	comp_buf_t *data;
	void *action;
	FILE *src, *dest;
	// check_argc
	if(argc != 4) goto do_usage;
	cmd = args[1][0];
	if(args[1][1] != '\0') goto do_usage;
	// which cmd?
	switch(cmd) {
		case 'C':
		case 'c':
			action = &&do_compress;
			break;
		case 'D':
		case 'd':
			action = &&do_decompress;
			break;
		default:
			goto do_usage;
	}
	// open files
	data = (comp_buf_t*)malloc(sizeof(comp_buf_t));
	if(data == 0) panic("m1");
	src = fopen(args[2],"rb"); if(src == 0) panic("m2");
	dest = fopen(args[3],"wb"); if(dest == 0) panic("m3");
	// process files
	goto *action;
do_compress:
	data->f = dest;
	ch = fgetc(src);
	while(ch != EOF) {
		write_compressed(data,ch);
		ch = fgetc(src);
	}
	flush_compressed(data);
	goto done;
do_decompress:
	data->f = src;
	do {
		block_decompress(data);
		if(data->len != fwrite(data->buf,sizeof(unsigned char),data->len,dest)) panic("m4");
	} while(!feof(src));
	goto done;
done:
	// close files
	fclose(src);
	fclose(dest);
	free(data);
	return 0;
do_usage:
	fprintf(stderr,
		"USAGE:\n"
		"\tcomptest cmd src_filename dest_filename\n"
		"\t\tcmd: \'c\' to compress, \'d\' to decompress\n");
	return 1;
}