iris.to nostr-my-profile-and-follows.json -> NostrFlu follower list converter

// SPDX-License-Identifier: WTFPL
// cc -Wall -O2 -I/usr/local/include -L/usr/local/lib -ljansson iris2flu.c -o iris2flu

#include <stdio.h>
#include <jansson.h>

static void build_relay_list(json_t *content)
{
	printf("# relays: %s\x0d\x0a", json_string_value(content));
}

static void build_follow_list(json_t *tags)
{
	int index;
	json_t *value;

	json_array_foreach (tags, index, value) {
		if (*json_string_value(json_array_get(value, 0)) == 'p' &&
		    json_string_length(json_array_get(value, 1))) {
			printf("%s\x0d\x0a",
			       json_string_value(json_array_get(value, 1)));
		}
	}
}

int main(int argc, char *argv[])
{
	json_t *root, *object, *tags, *content;
	json_error_t error;

	if (argc < 2) {
		printf("usage: %s [filename]\n", argv[0]);
		goto fin0;
	}

	if ((root = json_load_file(argv[1], 0, &error)) == NULL) {
		printf("file open error\n");
		goto fin0;
	}

	// event object is inside array
	if ((object = json_array_get(root, 0)) == NULL) {
		printf("invalid JSON array\n");
		goto fin1;
	}

	if (json_integer_value(json_object_get(object, "kind")) != 3 ||
	    (content = json_object_get(object, "content")) == NULL ||
	    (tags = json_object_get(object, "tags")) == NULL) {
		printf("invalid JSON content\n");
		goto fin1;
	}

	build_relay_list(content);
	build_follow_list(tags);

fin1:
	json_decref(root);
fin0:
	return 0;
}