/*
Copyright 2020 Google LLC

Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file or at
https://developers.google.com/open-source/licenses/bsd
*/

#include "system.h"

#include "basics.h"
#include "constants.h"
#include "pq.h"
#include "record.h"
#include "reftable-tests.h"
#include "test_framework.h"

void merged_iter_pqueue_check(struct merged_iter_pqueue pq)
{
	int i;
	for (i = 1; i < pq.len; i++) {
		int parent = (i - 1) / 2;

		EXPECT(pq_less(&pq.heap[parent], &pq.heap[i]));
	}
}

static void test_pq(void)
{
	struct merged_iter_pqueue pq = { NULL };
	struct reftable_record recs[54];
	int N = ARRAY_SIZE(recs) - 1, i;
	char *last = NULL;

	for (i = 0; i < N; i++) {
		struct strbuf refname = STRBUF_INIT;
		strbuf_addf(&refname, "%02d", i);

		reftable_record_init(&recs[i], BLOCK_TYPE_REF);
		recs[i].u.ref.refname = strbuf_detach(&refname, NULL);
	}

	i = 1;
	do {
		struct pq_entry e = {
			.rec = &recs[i],
		};

		merged_iter_pqueue_add(&pq, &e);
		merged_iter_pqueue_check(pq);

		i = (i * 7) % N;
	} while (i != 1);

	while (!merged_iter_pqueue_is_empty(pq)) {
		struct pq_entry e = merged_iter_pqueue_remove(&pq);
		merged_iter_pqueue_check(pq);

		EXPECT(reftable_record_type(e.rec) == BLOCK_TYPE_REF);
		if (last)
			EXPECT(strcmp(last, e.rec->u.ref.refname) < 0);
		last = e.rec->u.ref.refname;
	}

	for (i = 0; i < N; i++)
		reftable_record_release(&recs[i]);
	merged_iter_pqueue_release(&pq);
}

int pq_test_main(int argc, const char *argv[])
{
	RUN_TEST(test_pq);
	return 0;
}