#include <assert.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>


typedef __uint32_t art_id;


int main()
{
	FILE *in_file;
	FILE *out_file;

	art_id titles;

	art_id **linko;
	art_id *linkos;

	art_id **linki;
	art_id *linkis;

	art_id link_titles_done = 0;

	art_id i;


	/*
	 * Read all outgoing links into memory
	 */

	in_file = fopen("links-outgoing.bin", "rb");

	fread(&titles, sizeof(titles), 1, in_file);

	linko = malloc(titles * sizeof(art_id*));
	linkos = malloc(titles * sizeof(art_id));

	for (i = 0; i < titles; i++) {
		art_id j;

		fread(&linkos[i], sizeof(linkos[i]), 1, in_file);

		linko[i] = malloc(linkos[i] * sizeof(linko[i][0]));

		for (j = 0; j < linkos[i]; j++) {
			fread(&linko[i][j], sizeof(linko[i][j]), 1, in_file);
		}
	}
	fclose(in_file);

	printf("Outgoing links read.\n");



	linki = malloc(titles * sizeof(art_id*));
	linkis = malloc(titles * sizeof(art_id));

	for (i = 0; i < titles; i++) {
		art_id j;

		for (j = 0; j < linkos[i]; j++) {
			art_id x = linko[i][j];

			linkis[x]++;
			linki[x] = realloc(linki[x], linkis[x] * sizeof(linki[x][0]));

			linki[x][linkis[x] - 1] = i;
		}
	}

	printf("Links turned upside down.\n");



	out_file = fopen("links-incoming.bin", "wb");
	fwrite(&titles, sizeof(titles), 1, out_file);
	for (i = 0; i < titles; i++) {
		art_id j;

		fwrite(&linkis[i], sizeof(linkis[i]), 1, out_file);

		for (j = 0; j < linkis[i]; j++) {
			fwrite(&linki[i][j], sizeof(linki[i][j]), 1, out_file);
		}
	}
	fclose(out_file);

	printf("Incoming links written.\n");
}