#include "pw.h"
#include "tap.h"

// posix for clock/timer functions
#define _POSIX_C_SOURCE 200112L

#include <math.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

bool get_monotonic_timestamp(double *ts);

int main(int argc, char **argv){
	sqlite3 *db = NULL;
	int rc;

	if (argc != 2)
	{
		fprintf(stderr, "Usage: %s DATABASE\n", argv[0]);
		goto fail;
	}
	rc = sqlite3_open(argv[1], &db);
	if( rc ){
		fprintf(stderr, "Can't open database: %s\n", sqlite3_errmsg(db));
		goto fail;
	}

	pw_context *ctx;
	pw_init_context(db, &ctx);

	char *u1  = "foo@example.com", *p1 = "password123",
		 *u1c = "FOO@EXAMPLE.COM";

	plan(9);

	ok(PW_OK == pw_set(ctx, u1, p1), "pw_set");

	ok(PW_OK == pw_check(ctx, u1, p1),
		"pw_check accepts the same credentials");

	ok(PW_OK == pw_check(ctx, u1c, p1),
		"pw_check also accepts mixed case user");
	ok(PW_BAD_PASS == pw_check(ctx, u1, "wrong"),
		"pw_check fails for wrong pass");
	ok(PW_NO_USER == pw_check(ctx, "fake", "wrong"),
		"pw_check fails for missing user");

	unsigned char *tok;
	unsigned int tok_len;

	ok(PW_OK == pw_token_create(ctx, u1, &tok, &tok_len),
		"pw_token_create can build one");
	cmp_ok(tok_len, "==", 16,
		"token has expected length");

	int i;
	double start, end,
	       t_found, t_notfound,
		   pct_diff;

	diag("check password 100 times");
	get_monotonic_timestamp(&start);
	for (i = 0; i < 100; i++)
		pw_check(ctx, u1, p1);
	get_monotonic_timestamp(&end);
	t_found = end - start;

	diag("check 100 times for missing user");
	get_monotonic_timestamp(&start);
	for (i = 0; i < 100; i++)
		pw_check(ctx, "fake", "wrong");
	get_monotonic_timestamp(&end);
	t_notfound = end - start;

	pct_diff = 100.0 *
		fabs( (t_found - t_notfound) / ((t_found + t_notfound)/2) );

	cmp_ok(pct_diff, "<", 1.0, "less than 1%% time difference");

	free(ctx);
	sqlite3_close(db);
	return 0;

fail:
	sqlite3_close(db);
	return EXIT_FAILURE;
}

// idea for using double representation taken from
// https://github.com/solemnwarning/timespec
#define NSEC_PER_SEC 1000000000
bool get_monotonic_timestamp(double *ts)
{
	struct timespec now;
	int rc = clock_gettime(CLOCK_MONOTONIC, &now);
	if (rc != 0)
		return false;
	*ts = (
		 ((double)now.tv_sec) +
		(((double)now.tv_nsec) / NSEC_PER_SEC)
	);
	return true;
}