/*
 * 989_globstructret_run — F8-c6 (report-item #41, #263): returning a module-
 * GLOBAL struct ident by value (`return g;`) must copy g's bytes into the
 * return buffer.
 *
 * THE BUG (cat-A silent miscompile, #263 BOTH-WRONG, now CLOSED both stages):
 * the ≤24B register-struct return path word-copied an N_IDENT source from its
 * BP slot only for a LOCAL ident. A module-global struct ident hit no branch
 * (wwstage zero-filled the @retscr; cstage copied frame garbage ((BP)/8(BP)),
 * never g(SB)). The ww half landed in F8-c6; the cstage half (route a global
 * ident through the aggarg_srcaddr memcpy — LEAQ g(SB),SI) landed in ww-core
 * TASK #42. Both stages now copy g's bytes and the .s is byte-identical.
 *
 * Rows assert the field-equality check returns 0 on both stages (cs==ww).
 *   row        | shape (return g; then check)              | exit
 *   -----------+-------------------------------------------+-----
 *   ret_16     | point{x=3,y=4} (rsz 16); x==3 && y==4      | 0
 *   ret_24     | triple{a=5,b=6,c=7} (rsz 24); all three    | 0
 */
#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;
}

struct row {
	const char *label;
	const char *src;
	int want_cs;
	int want_ww;
};

static const struct row rows[] = {
	{ "ret_16",
	  "package main;\n"
	  "type point = struct { x: i64, y: i64 };\n"
	  "let g: point = point { x = 3, y = 4 };\n"
	  "fn get() point = { return g; };\n"
	  "export fn main() int = {\n"
	  "	let p: point = get();\n"
	  "	if (p.x == 3 && p.y == 4) { return 0; };\n"
	  "	return 1;\n"
	  "};\n",
	  0, 0 },

	{ "ret_24",
	  "package main;\n"
	  "type triple = struct { a: i64, b: i64, c: i64 };\n"
	  "let g: triple = triple { a = 5, b = 6, c = 7 };\n"
	  "fn get() triple = { return g; };\n"
	  "export fn main() int = {\n"
	  "	let p: triple = get();\n"
	  "	if (p.a == 5 && p.b == 6 && p.c == 7) { return 0; };\n"
	  "	return 1;\n"
	  "};\n",
	  0, 0 },
};

/* run_build — build+run `src` via `driver`; returns the binary's exit
 * code, or -1 on a build failure. */
static int
run_build(const char *driver, const struct row *r, int i)
{
	char src[64], tmpdir[64], cmd[1024];
	snprintf(src, sizeof src, "/tmp/gsr_%d_%d.ww", getpid(), i);
	snprintf(tmpdir, sizeof tmpdir, "/tmp/gsr_%d_d_%d", getpid(), i);

	FILE *f = fopen(src, "wb");
	if (!f) return -2;
	fputs(r->src, f);
	fclose(f);

	mkdir(tmpdir, 0755);
	snprintf(cmd, sizeof cmd, "cd %s && %s build %s 2>/dev/null",
	    tmpdir, driver, src);
	int brc = runwait(cmd);

	const char *base = strrchr(src, '/');
	base = base ? base + 1 : src;
	char outbin[128];
	snprintf(outbin, sizeof outbin, "%s/%s", tmpdir, base);
	char *dot = strrchr(outbin, '.');
	if (dot && strcmp(dot, ".ww") == 0) *dot = '\0';

	int got = -1;
	if (brc == 0) got = runwait(outbin);

	unlink(src); unlink(outbin); rmdir(tmpdir);
	return brc == 0 ? got : -1;
}

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);

	struct { const char *name; const char *drv; int gated; }
	drivers[] = {
		{ "cstage",  cdrv, 0 },
		{ "wwstage", wdrv, 1 },
		{ NULL, NULL, 0 },
	};

	int n = (int)(sizeof rows / sizeof rows[0]);
	int total = 0, fail = 0;

	for (int d = 0; drivers[d].name; d++) {
		if (drivers[d].gated && access(drivers[d].drv, X_OK) != 0) {
			fprintf(stderr, "globstructret_run: skip %s (no %s)\n",
			    drivers[d].name, drivers[d].drv);
			continue;
		}
		int is_ww = (d == 1);
		for (int i = 0; i < n; i++) {
			total++;
			int want = is_ww ? rows[i].want_ww : rows[i].want_cs;
			int got = run_build(drivers[d].drv, &rows[i], i);
			if (got != want) {
				fprintf(stderr, "globstructret_run[%s][%s]: exit=%d "
				    "want=%d\n", drivers[d].name, rows[i].label,
				    got, want);
				fail++;
			}
		}
	}

	if (fail) {
		fprintf(stderr, "globstructret_run: %d/%d fixtures failed\n",
		    fail, total);
		return 1;
	}
	printf("globstructret_run: %d/%d ok\n", total, total);
	return 0;
}