// 27 february 2018
#include <stdio.h>
#include <stdlib.h>
#include <setjmp.h>
#include <string.h>
#include "testing.h"

#define testingprivNew(T) ((T *) malloc(sizeof (T)))

struct defer {
	void (*f)(testingT *, void *);
	void *data;
	struct defer *next;
};

#ifdef _MSC_VER
// Microsoft defines jmp_buf with a __declspec(align()), and for whatever reason, they have a warning that triggers when you use that for any reason, and that warning is enabled with /W4
// Silence the warning; it's harmless.
#pragma warning(push)
#pragma warning(disable: 4324)
#endif

struct testingT {
	const char *name;
	void (*f)(testingT *);
	const char *file;
	long line;
	int failed;
	int skipped;
	int returned;
	jmp_buf returnNowBuf;
	struct defer *defers;
	int defersRun;
};

#ifdef _MSC_VER
#pragma warning(pop)
#endif

static void initTest(testingT *t, const char *name, void (*f)(testingT *), const char *file, long line)
{
	t->name = name;
	t->f = f;
	t->file = file;
	t->line = line;
	t->failed = 0;
	t->skipped = 0;
	t->returned = 0;
	t->defers = NULL;
	t->defersRun = 0;
}

#define nGrow 32

struct testset {
	testingT *tests;
	size_t len;
	size_t cap;
};

static struct testset tests = { NULL, 0, 0 };
static struct testset testsBefore = { NULL, 0, 0 };
static struct testset testsAfter = { NULL, 0, 0 };

static void testsetAdd(struct testset *set, const char *name, void (*f)(testingT *), const char *file, long line)
{
	if (set->len == set->cap) {
		testingT *newbuf;

		set->cap += nGrow;
		newbuf = (testingT *) realloc(set->tests, set->cap * sizeof (testingT));
		// TODO abort if newbuf is NULL
		set->tests = newbuf;
	}
	initTest(set->tests + set->len, name, f, file, line);
	set->len++;
}

void testingprivRegisterTest(const char *name, void (*f)(testingT *), const char *file, long line)
{
	testsetAdd(&tests, name, f, file, line);
}

void testingprivRegisterTestBefore(const char *name, void (*f)(testingT *), const char *file, long line)
{
	testsetAdd(&testsBefore, name, f, file, line);
}

void testingprivRegisterTestAfter(const char *name, void (*f)(testingT *), const char *file, long line)
{
	testsetAdd(&testsAfter, name, f, file, line);
}

static int testcmp(const void *a, const void *b)
{
	const testingT *ta = (const testingT *) a;
	const testingT *tb = (const testingT *) b;
	int ret;

	ret = strcmp(ta->file, tb->file);
	if (ret != 0)
		return ret;
	if (ta->line < tb->line)
		return -1;
	if (ta->line > tb->line)
		return 1;
	return 0;
}

static void testsetSort(struct testset *set)
{
	qsort(set->tests, set->len, sizeof (testingT), testcmp);
}

static void runDefers(testingT *t)
{
	struct defer *d;

	if (t->defersRun)
		return;
	t->defersRun = 1;
	for (d = t->defers; d != NULL; d = d->next)
		(*(d->f))(t, d->data);
}

static void testsetRun(struct testset *set, int *anyFailed)
{
	size_t i;
	testingT *t;
	const char *status;

	t = set->tests;
	for (i = 0; i < set->len; i++) {
		printf("=== RUN   %s\n", t->name);
		if (setjmp(t->returnNowBuf) == 0)
			(*(t->f))(t);
		t->returned = 1;
		runDefers(t);
		status = "PASS";
		if (t->failed) {
			status = "FAIL";
			*anyFailed = 1;
		} else if (t->skipped)
			// note that failed overrides skipped
			status = "SKIP";
		printf("--- %s: %s (%s)\n", status, t->name, "TODO");
		t++;
	}
}

int testingMain(void)
{
	int anyFailed;

	// TODO see if this should run if all tests are skipped
	if ((testsBefore.len + tests.len + testsAfter.len) == 0) {
		fprintf(stderr, "warning: no tests to run\n");
		// imitate Go here (TODO confirm this)
		return 0;
	}

	testsetSort(&testsBefore);
	testsetSort(&tests);
	testsetSort(&testsAfter);

	anyFailed = 0;
	testsetRun(&testsBefore, &anyFailed);
	// TODO print a warning that we skip the next stages if a prior stage failed?
	if (!anyFailed)
		testsetRun(&tests, &anyFailed);
	// TODO should we unconditionally run these tests if before succeeded but the main tests failed?
	if (!anyFailed)
		testsetRun(&testsAfter, &anyFailed);
	if (anyFailed) {
		printf("FAIL\n");
		return 1;
	}
	printf("PASS\n");
	return 0;
}

void testingprivTLogfFull(testingT *t, const char *file, long line, const char *format, ...)
{
	va_list ap;

	va_start(ap, format);
	testingprivTLogvfFull(t, file, line, format, ap);
	va_end(ap);
}

void testingprivTLogvfFull(testingT *t, const char *file, long line, const char *format, va_list ap)
{
	// TODO extract filename from file
	printf("\t%s:%ld: ", file, line);
	// TODO split into lines separated by \n\t\t and trimming trailing empty lines
	vprintf(format, ap);
	printf("\n");
}

void testingTFail(testingT *t)
{
	t->failed = 1;
}

static void returnNow(testingT *t)
{
	if (!t->returned) {
		// set this now so a FailNow inside a Defer doesn't longjmp twice
		t->returned = 1;
		// run defers before calling longjmp() just to be safe
		runDefers(t);
		longjmp(t->returnNowBuf, 1);
	}
}

void testingprivTFailNow(testingT *t)
{
	testingTFail(t);
	returnNow(t);
}

void testingprivTSkipNow(testingT *t)
{
	t->skipped = 1;
	returnNow(t);
}

void testingTDefer(testingT *t, void (*f)(testingT *t, void *data), void *data)
{
	struct defer *d;

	d = testingprivNew(struct defer);
	d->f = f;
	d->data = data;
	// add to the head of the list so defers are run in reverse order of how they were added
	d->next = t->defers;
	t->defers = d;
}