/*
 * 975_dirs_toolong_run — F14 #69: dirs silently truncated an over-long
 * composed path and then mkdir'd the WRONG directory, returning it rc=0.
 * The fix (dirs.ww build()) precomputes the composition length and
 * rt_aborts loudly when it won't fit the 256B pathbuf — mirroring Hare's
 * path::push too_long → `!` abort (ref/hare/dirs/xdg.ha). Both stages
 * share the lib, so this is a stdlib behavior fix, not a stage divergence;
 * the test still runs both driver twins for parity.
 *
 * One fixture program (dirs.config("prog"), print len) built per stage,
 * then run under two HOME states:
 *   - a short HOME → exit 0 (normal path intact, no regression);
 *   - a ~260-byte HOME → non-zero exit (loud abort) AND no stray
 *     directory created on disk.
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/wait.h>

static int
runwait(const char *cmd)
{
	int rc = system(cmd);
	if (rc == -1) return -1;
	if (WIFEXITED(rc)) return WEXITSTATUS(rc);
	return -1;
}

static const char *PROG =
	"package main;\n"
	"import dirs;\n"
	"import fmt;\n"
	"export fn main() int = {\n"
	"	let d = dirs.config(\"prog\");\n"
	"	fmt.println(d.len: i64);\n"
	"	return 0;\n"
	"};\n";

/* run_stage — build PROG with `driver`, then exercise the two HOME states.
 * Returns 0 on success, non-zero on any mismatch. */
static int
run_stage(const char *name, const char *driver)
{
	char src[64], tmpdir[64], cmd[2048];
	snprintf(src, sizeof src, "/tmp/dtl_%d.ww", getpid());
	snprintf(tmpdir, sizeof tmpdir, "/tmp/dtl_%d_d", getpid());

	FILE *f = fopen(src, "wb");
	if (!f) return 1;
	fputs(PROG, f);
	fclose(f);

	mkdir(tmpdir, 0755);
	snprintf(cmd, sizeof cmd, "cd %s && %s build %s 2>/dev/null",
	    tmpdir, driver, src);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "dirs_toolong[%s]: build failed\n", name);
		unlink(src); rmdir(tmpdir);
		return 1;
	}
	char outbin[128];
	snprintf(outbin, sizeof outbin, "%s/dtl_%d", tmpdir, getpid());

	int fail = 0;

	/* short HOME — the normal path, must still exit 0. */
	snprintf(cmd, sizeof cmd,
	    "env -u XDG_CONFIG_HOME HOME=/tmp/dtl_%d_home %s >/dev/null 2>&1",
	    getpid(), outbin);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "dirs_toolong[%s]: short HOME did not exit 0\n",
		    name);
		fail = 1;
	}

	/* ~260-byte HOME — must abort loudly (non-zero) and create no dir. */
	char longhome[512];
	int p = snprintf(longhome, sizeof longhome, "/tmp/dtl_%d_long_", getpid());
	for (int i = 0; i < 260 && p < (int)sizeof longhome - 1; i++)
		longhome[p++] = 'a';
	longhome[p] = '\0';

	snprintf(cmd, sizeof cmd,
	    "env -u XDG_CONFIG_HOME HOME=%s %s >/dev/null 2>&1",
	    longhome, outbin);
	if (runwait(cmd) == 0) {
		fprintf(stderr, "dirs_toolong[%s]: long HOME exited 0, "
		    "expected a loud abort\n", name);
		fail = 1;
	}
	/* the truncated wrong directory must NOT have been created. */
	snprintf(cmd, sizeof cmd, "test -e %s", longhome);
	if (runwait(cmd) == 0) {
		fprintf(stderr, "dirs_toolong[%s]: stray directory created\n",
		    name);
		fail = 1;
		snprintf(cmd, sizeof cmd, "rm -rf %s", longhome);
		(void)system(cmd);
	}

	unlink(src); unlink(outbin); rmdir(tmpdir);
	snprintf(cmd, sizeof cmd, "rm -rf /tmp/dtl_%d_home", getpid());
	(void)system(cmd);
	return fail;
}

int
main(void)
{
	const char *bin = getenv("BIN");
	if (!bin) bin = "out/bin";
	char absbin[1024];
	if (bin[0] != '/') {
		char cwd[1024];
		if (getcwd(cwd, sizeof cwd) == NULL) return 1;
		snprintf(absbin, sizeof absbin, "%s/%s", cwd, bin);
		bin = absbin;
	}

	char cdrv[1024], wdrv[1024];
	snprintf(cdrv, sizeof cdrv, "%s/ww", bin);
	snprintf(wdrv, sizeof wdrv, "%s/ww_ww", bin);

	int fail = 0;
	fail += run_stage("cstage", cdrv);
	if (access(wdrv, X_OK) == 0)
		fail += run_stage("wwstage", wdrv);
	else
		fprintf(stderr, "dirs_toolong: skip wwstage (no %s)\n", wdrv);

	if (fail) {
		fprintf(stderr, "dirs_toolong: %d stage(s) failed\n", fail);
		return 1;
	}
	printf("dirs_toolong: ok\n");
	return 0;
}