/*
 * The white-box half must be the -T root: dependency packages lose @test
 * declarations before code generation. Keep it separate from the external
 * regex_test binary because each -T unit owns main and __wwtests.
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/wait.h>

static const char *whitebox[] = {
	"thread_shape",
	"newmatch_discriminates",
	"is_consuming_kinds",
	"delete_thread_middle",
	"add_thread_dedup_inherit",
	"add_thread_dup_independence",
	"run_thread_literal_program",
	"run_thread_anchored_route",
	"search_matches",
	"search_early_exit",
	"search_no_match",
	"find_last_groupstart_cases",
	"shift_direct",
	"run_thread_group_arms",
	"parse_repetition_cases",
};

static int
runwait(const char *cmd)
{
	int rc;

	rc = system(cmd);
	if (rc == -1)
		return -1;
	if (WIFEXITED(rc))
		return WEXITSTATUS(rc);
	return 1;
}

static int
runcapture(const char *cmd, char *out, size_t outsz)
{
	FILE *p;
	size_t n;
	int ch, overflow, status;

	p = popen(cmd, "r");
	if (p == NULL)
		return -1;
	n = 0;
	overflow = 0;
	while ((ch = fgetc(p)) != EOF) {
		if (n + 1 < outsz)
			out[n++] = ch;
		else
			overflow = 1;
	}
	out[n] = '\0';
	status = pclose(p);
	if (overflow || status == -1)
		return -1;
	if (WIFEXITED(status))
		return WEXITSTATUS(status);
	return 1;
}

static int
linecount(const char *out, const char *want)
{
	const char *p, *end;
	size_t n;
	int count;

	n = strlen(want);
	count = 0;
	for (p = out; *p != '\0'; p = *end == '\0' ? end : end + 1) {
		end = strchr(p, '\n');
		if (end == NULL)
			end = p + strlen(p);
		if ((size_t)(end - p) == n && memcmp(p, want, n) == 0)
			count++;
	}
	return count;
}

static int
okcount(const char *out)
{
	const char *p, *end;
	static const char suffix[] = " ... ok";
	size_t n, slen;
	int count;

	slen = sizeof suffix - 1;
	count = 0;
	for (p = out; *p != '\0'; p = *end == '\0' ? end : end + 1) {
		end = strchr(p, '\n');
		if (end == NULL)
			end = p + strlen(p);
		n = (size_t)(end - p);
		if (n >= slen && memcmp(end - slen, suffix, slen) == 0)
			count++;
	}
	return count;
}

static int
checkresult(const char *label, const char *out, int expected,
	const char *const *names, size_t nnames)
{
	char summary[64], row[256];
	int bad;

	bad = 0;
	snprintf(summary, sizeof summary, "%d passed, 0 failed", expected);
	if (linecount(out, summary) != 1 || okcount(out) != expected
	    || strstr(out, "FAIL") != NULL || strstr(out, "No tests run") != NULL) {
		fprintf(stderr, "regex_run FAIL: %s result was incomplete\n%s",
		    label, out);
		bad = 1;
	}
	for (size_t i = 0; i < nnames; i++) {
		snprintf(row, sizeof row, "%s ... ok", names[i]);
		if (linecount(out, row) != 1) {
			fprintf(stderr, "regex_run FAIL: %s did not execute exactly once\n",
			    names[i]);
			bad = 1;
		}
	}
	return bad ? -1 : 0;
}

int
main(void)
{
	const char *bin;
	char absbin[1024], cwd[1024], tmp[] = "/tmp/wwregex.XXXXXX";
	char cmd[4096], output[32768], cleanup[1200];
	int rc, failed;

	bin = getenv("BIN");
	if (bin == NULL)
		bin = "out/bin";
	if (bin[0] != '/') {
		if (getcwd(cwd, sizeof cwd) == NULL)
			return 1;
		if (snprintf(absbin, sizeof absbin, "%s/%s", cwd, bin)
		    >= (int)sizeof absbin)
			return 1;
		bin = absbin;
	}
	if (getcwd(cwd, sizeof cwd) == NULL)
		return 1;
	if (mkdtemp(tmp) == NULL)
		return 1;

	failed = 0;
	/* A unique cwd prevents an unrelated local `regex` path from winning
	 * the module lookup; the private cache keeps the source tree untouched. */
	if (snprintf(cmd, sizeof cmd,
	    "cd '%s' && WW_PKGCACHE='%s/cache-black' timeout 180 '%s/ww' "
	    "test -I '%s/lib' '%s/lib/regex/regex_test.ww'",
	    tmp, tmp, bin, cwd, cwd) >= (int)sizeof cmd) {
		failed = 1;
	} else {
		rc = runcapture(cmd, output, sizeof output);
		if (rc != 0 || checkresult("black-box", output, 33, NULL, 0) != 0) {
			fprintf(stderr, "regex_run FAIL: black-box exited %d\n", rc);
			failed = 1;
		} else {
			printf("regex_run: black-box 33 discovered, 33 passed, 0 failed\n");
		}
	}

	/* Resolving the package directory as the root keeps -T off imported
	 * dependencies while making every in-package probe visible to the synth. */
	if (snprintf(cmd, sizeof cmd,
	    "cd '%s' && WW_PKGCACHE='%s/cache-white' timeout 180 '%s/ww' "
	    "test -I '%s/lib' regex", tmp, tmp, bin, cwd) >= (int)sizeof cmd) {
		failed = 1;
	} else {
		rc = runcapture(cmd, output, sizeof output);
		if (rc != 0 || checkresult("white-box", output, 15, whitebox,
		    sizeof whitebox / sizeof whitebox[0]) != 0) {
			fprintf(stderr, "regex_run FAIL: white-box exited %d\n", rc);
			failed = 1;
		} else {
			printf("regex_run: white-box 15 discovered, 15 passed, 0 failed\n");
		}
	}

	snprintf(cleanup, sizeof cleanup, "rm -rf -- '%s'", tmp);
	if (runwait(cleanup) != 0) {
		fprintf(stderr, "regex_run FAIL: cannot clean temporary directory\n");
		failed = 1;
	}
	return failed ? 1 : 0;
}