/*
 * 689_globptr_field_store_run (#6) — a module-GLOBAL `*struct` pointer base
 * (`gp.f = v` / `gp.f += v` / `gp.x.y = v` / `gp.a[i].f = v`) stores
 * correctly AND cstage / wwstage agree byte-for-byte.
 *
 * THE BUG (cstage only): a global `*struct` ptr base carries via_ptr=1 but
 * has no local slot — localfind returns 0, so the enumerated via_ptr field-
 * store arms emitted `MOVQ (BP),BX` (deref the saved BP = garbage → SEGV).
 * The plain-scalar-`=` STORE half was already correct (the #47/#8 fix, LEAQ
 * gp(SB)), so load/store were asymmetric. wwstage routes every case EXCEPT
 * plain-scalar-`=` through its F6 cgplaceaddr resolver and was correct.
 *
 * THE FIX (align cstage UP): decline the global-`*struct`-ptr base at the
 * enumerated arm's dispatch for compound + non-scalar (and a chained
 * `gp.x.y` root), so cstage falls to its OWN F6 assign-resolver — byte-
 * identical to wwstage. Plain-scalar-`=` stays in the enumerated arm (its
 * #47 byte-id is undisturbed); a local ptr and a param at offset 0
 * (localfind != 0) also stay local.
 *
 *   shape                         | want
 *   ------------------------------+------
 *   gp.f += 5   (compound off 8)  | 5
 *   gp.f += 7   (compound off 0)  | 7
 *   gp.in = Inner{7,9} (struct)   | 16
 *   gp.sf = "hi" (str field)      | 2
 *   gp.x.y=11; gp.x.z+=7 (chain)  | 18
 *   gp.a[1].f=5; gp.a[1].g+=8     | 13
 *   lp.f += 5   (LOCAL ptr ctrl)  | 5
 *   bump(&s): p.f/p.g (param ctrl)| 10
 * Each row also asserts w6c .s == w6c_ww .s byte-identical.
 * Pre-fix: cstage SEGV(139) on every global-ptr row; cs vs ww .s differed.
 */
#include <stdio.h>
#include <stdlib.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 *name;
	const char *src;
	int want;
};

static const struct row ROWS[] = {
{ "compound_off8",
	"package main;\n"
	"type S = struct { a: i64, f: i64 };\n"
	"let gp: *S = nil;\n"
	"export fn main() i32 = { let s: S = S{a=0,f=0}; gp = &s;"
	" gp.f += 5; return s.f: i32; };\n", 5 },
{ "compound_off0",
	"package main;\n"
	"type S = struct { f: i64, g: i64 };\n"
	"let gp: *S = nil;\n"
	"export fn main() i32 = { let s: S = S{f=0,g=0}; gp = &s;"
	" gp.f += 7; return s.f: i32; };\n", 7 },
{ "struct_field",
	"package main;\n"
	"type I = struct { x: i64, y: i64 };\n"
	"type S = struct { a: i64, in: I };\n"
	"let gp: *S = nil;\n"
	"export fn main() i32 = { let s: S = S{a=0,in=I{x=0,y=0}}; gp = &s;"
	" gp.in = I{x=7,y=9}; return (s.in.x+s.in.y): i32; };\n", 16 },
{ "str_field",
	"package main;\n"
	"type S = struct { a: i64, sf: str };\n"
	"let gp: *S = nil;\n"
	"export fn main() i32 = { let s: S = S{a=0,sf=\"\"}; gp = &s;"
	" gp.sf = \"hi\"; return (s.sf.len): i32; };\n", 2 },
{ "chained",
	"package main;\n"
	"type I = struct { y: i64, z: i64 };\n"
	"type S = struct { a: i64, x: I };\n"
	"let gp: *S = nil;\n"
	"export fn main() i32 = { let s: S = S{a=0,x=I{y=0,z=0}}; gp = &s;"
	" gp.x.y = 11; gp.x.z += 7; return (s.x.y+s.x.z): i32; };\n", 18 },
{ "indexed",
	"package main;\n"
	"type E = struct { f: i64, g: i64 };\n"
	"type S = struct { n: i64, a: [3]E };\n"
	"let gp: *S = nil;\n"
	"export fn main() i32 = { let s: S; gp = &s;"
	" gp.a[1].f = 5; gp.a[1].g += 8; return (s.a[1].f+s.a[1].g): i32; };\n", 13 },
{ "local_ptr_ctrl",
	"package main;\n"
	"type S = struct { a: i64, f: i64 };\n"
	"export fn main() i32 = { let s: S = S{a=0,f=0}; let lp: *S = &s;"
	" lp.f += 5; return s.f: i32; };\n", 5 },
{ "param_off0_ctrl",
	"package main;\n"
	"type S = struct { f: i64, g: i64 };\n"
	"fn bump(p: *S) void = { p.f += 3; p.g += 4; };\n"
	"export fn main() i32 = { let s: S = S{f=1,g=2}; bump(&s);"
	" return (s.f+s.g): i32; };\n", 10 },
};

#define NROWS ((int)(sizeof ROWS / sizeof ROWS[0]))

/* build+run one row through `driver`; return exit code or -1. */
static int
run_driver(const char *driver, const char *src, int idx)
{
	char tmpdir[64], srcf[128], outbin[160], rmcmd[192], cmd[2400];
	snprintf(tmpdir, sizeof tmpdir, "/tmp/gpfs_%d_%d_d", getpid(), idx);
	mkdir(tmpdir, 0755);
	snprintf(srcf,   sizeof srcf,   "%s/t.ww", tmpdir);
	snprintf(outbin, sizeof outbin, "%s/t",    tmpdir);
	snprintf(rmcmd,  sizeof rmcmd,  "rm -rf %s", tmpdir);

	FILE *f = fopen(srcf, "wb");
	if (!f) { runwait(rmcmd); return -1; }
	fputs(src, f);
	fclose(f);

	snprintf(cmd, sizeof cmd, "%s build -o %s %s 2>/dev/null",
	    driver, outbin, srcf);
	if (runwait(cmd) != 0) { runwait(rmcmd); return -1; }
	int got = runwait(outbin);
	runwait(rmcmd);
	return got;
}

/* emit .s for `tool` (w6c / w6c_ww) into asmf; 0 ok, -1 on compile fail. */
static int
emit_asm(const char *bin, const char *tool, const char *src, int idx,
    const char *asmf)
{
	char srcf[80], cmd[2400];
	snprintf(srcf, sizeof srcf, "/tmp/gpfs_asm_%d_%d.ww", getpid(), idx);
	FILE *f = fopen(srcf, "wb");
	if (!f) return -1;
	fputs(src, f);
	fclose(f);
	snprintf(cmd, sizeof cmd, "%s/%s -o %s %s 2>/dev/null",
	    bin, tool, asmf, srcf);
	int rc = runwait(cmd);
	unlink(srcf);
	return rc == 0 ? 0 : -1;
}

static int
files_identical(const char *a, const char *b)
{
	FILE *fa = fopen(a, "rb"), *fb = fopen(b, "rb");
	if (!fa || !fb) { if (fa) fclose(fa); if (fb) fclose(fb); return 0; }
	int ca, cb, same = 1;
	do {
		ca = fgetc(fa); cb = fgetc(fb);
		if (ca != cb) { same = 0; break; }
	} while (ca != EOF);
	fclose(fa); fclose(fb);
	return same;
}

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 have_ww = (access(wdrv, X_OK) == 0);

	int fail = 0, total = 0;
	for (int i = 0; i < NROWS; i++) {
		const struct row *r = &ROWS[i];

		total++;
		int gc = run_driver(cdrv, r->src, i);
		if (gc != r->want) {
			fprintf(stderr, "globptr_field_store[%s,cstage]: run=%d want=%d\n",
			    r->name, gc, r->want);
			fail++;
		}
		if (have_ww) {
			total++;
			int gw = run_driver(wdrv, r->src, i);
			if (gw != r->want) {
				fprintf(stderr, "globptr_field_store[%s,wwstage]: run=%d want=%d\n",
				    r->name, gw, r->want);
				fail++;
			}
		}

		/* byte-id: w6c .s == w6c_ww .s */
		if (have_ww) {
			char csf[80], wwf[80];
			snprintf(csf, sizeof csf, "/tmp/gpfs_cs_%d_%d.s", getpid(), i);
			snprintf(wwf, sizeof wwf, "/tmp/gpfs_ww_%d_%d.s", getpid(), i);
			total++;
			int ec = emit_asm(bin, "w6c", r->src, i, csf);
			int ew = emit_asm(bin, "w6c_ww", r->src, i, wwf);
			if (ec != 0 || ew != 0 || !files_identical(csf, wwf)) {
				fprintf(stderr, "globptr_field_store[%s]: cs/ww .s NOT "
				    "byte-identical (ec=%d ew=%d)\n", r->name, ec, ew);
				fail++;
			}
			unlink(csf); unlink(wwf);
		}
	}

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