/*******************************************************************
 *                                                                 *
 * Working with utf8 only file encoding.                           *
 * This program reads file, and prints same file without words,    *
 * that not consist of numbers and numbers ending with "-й"        *
 *                                                                 *
 *******************************************************************/

#include <stdio.h>
#include <stdlib.h>

#define BUF_SIZE 128

void process_output_buf(unsigned char* output_buf, int buf_size);
void clear_output_buf(unsigned char* output_buf, int buf_size);
unsigned char* realloc_output_buf(unsigned char* output_buf, int prev_size, int new_size);

int main(int argc, char *argv[]) {
	FILE *fp = NULL;
	unsigned char* output_buf = NULL;
	unsigned char file_buf[BUF_SIZE] = { 0 };
	int ob_i = 0;
	int ob_size = BUF_SIZE;

	output_buf = calloc(BUF_SIZE, sizeof(unsigned char));
	if(output_buf == NULL) {
		printf("Couldn't allocate memory.\n");
		exit(4);
	}

	if(argc != 2) {
		printf("Incorrect number of arguments.\n");
		exit(1);
	}

	if((fp = fopen(argv[1], "rb") ) == NULL) {
		printf("Cannot open file.\n");
		exit(2);
	}

	while(1) {
		if(fgets(file_buf, BUF_SIZE, fp)) {
			for(int i = 0; i < BUF_SIZE, file_buf[i] != '\0'; i++) {
				if(file_buf[i] == 32 || file_buf[i] == 10) {
					process_output_buf(output_buf, ob_size);
					clear_output_buf(output_buf, ob_size);
					ob_i = 0;

					printf("%c", file_buf[i]);
				} else {
					output_buf[ob_i] = file_buf[i];
					ob_i++;
					if(ob_i >= ob_size) {
						output_buf = realloc_output_buf(output_buf, ob_size, ob_size + BUF_SIZE);
						ob_size += BUF_SIZE;
					}
				}
			}
		} else {
			if(ferror(fp)) {
				printf("Error while reading file.\n");
				exit(3);
			}

			break;
		}
	}

	process_output_buf(output_buf, ob_size);

	fclose(fp);
	free(output_buf);

	return 0;
}

void process_output_buf(unsigned char* output_buf, int buf_size) {
	if(buf_size < 1) return;

	if(48 <= output_buf[0] && output_buf[0] < 58) {
		for(int i = 1; i < buf_size, output_buf[i] != 0; i++) {
			if(48 <= output_buf[i] && output_buf[i] < 58) {
				continue;
			} else if(output_buf[i] == 45) { // -й
				if((i + 2) < buf_size) {
					if((output_buf[i + 1] == 208) && (output_buf[i + 2] == 185)) {
						printf("%s", output_buf);
					}
				}
			}

			return;
		}

		printf("%s", output_buf);
	}
}

void clear_output_buf(unsigned char* output_buf, int buf_size) {
	for(int i = 0; i < buf_size; i++) {
		output_buf[i] = 0;
	}
}

unsigned char* realloc_output_buf(unsigned char* output_buf, int prev_size, int new_size) {
	output_buf = realloc(output_buf, new_size * sizeof(unsigned char));
	if(output_buf == NULL) {
		printf("Couldn't allocate memory.\n");
		exit(4);
	}

	for(int i = prev_size; i < new_size; i++) {
		output_buf[i] = 0;
	}

	return output_buf;
}