/*
 * 949_dotfield_compound_run — runtime + byte-id net for #34 (#263 both-
 * stages): a compound assign on a single-dot field lvalue
 * (`s.f OP= v`, `p.f OP= v`, `g.f OP= v`, `sl.len OP= v`) must do a real
 * LOAD-OP-STORE for ALL ten integer ops, not silently demote any op
 * other than += / -= to a plain `s.f = rhs`.
 *
 * Pre-fix: every single-dot field-compound arm in BOTH stages wired only
 * PLUSEQ/MINUSEQ; *= /= %= &= |= ^= <<= >>= left the old value in BX and
 * the rhs in AX, then fell into the generic store of AX — `s.f *= 3`
 * silently compiled to `s.f = 3` (gate-blind, .s byte-identical). The
 * five sub-arms (via-ptr-base local, direct struct local, str/slice
 * pseudo-field, global struct field) all shared the BX=old/AX=rhs
 * convention; the fix routes every one through one shared combine helper
 * (cgdotfieldcombine / cg_dotfield_combine) wiring all 10 ops and
 * hard-errors float/str/slice/tagged fields LOUD (rule-7). cs/ww move
 * together (#263 carve-out); byte-id witnesses rule-10.
 *
 * Each row carries (a) a cstage `ww build` + run asserting the exit code
 * and (b) a w6c vs w6c_ww `.s` cmp (rule-10 byte-id). builderr rows
 * assert BOTH stages fail loud with the cited diagnostic substring.
 */
#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;
}

/* builderr + experr: when builderr != 0 the cstage build MUST FAIL and
 * stderr MUST contain experr. wwstage builderr is verified via direct
 * w6c_ww invocation on the same source. Mirrors 945_tuple_nary's pattern
 * for loud-stop verification (rule 7 — never silent). */
struct row { const char *label; const char *src; int want_exit;
             int builderr; const char *experr; };

static const struct row rows[] = {
	/* += control: the base op was already wired — byte-id surface
	 * unchanged. 10 + 5 = 15. */
	{ "dotfld_pluseq_ctrl",
	  "package main;\n"
	  "type S = struct { f: int, g: int };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=10, g=0};\n"
	  "	s.f += 5;\n"
	  "	return s.f: i32;\n"
	  "};\n", 15, 0, NULL },
	/* #34 newly-wired: direct struct local *= : 5 * 3 = 15. */
	{ "dotfld_stareq",
	  "package main;\n"
	  "type S = struct { f: int, g: int };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=5, g=0};\n"
	  "	s.f *= 3;\n"
	  "	return s.f: i32;\n"
	  "};\n", 15, 0, NULL },
	/* signed /= : 100 / 4 = 25 (CQO+IDIVQ). */
	{ "dotfld_slasheq_signed",
	  "package main;\n"
	  "type S = struct { f: int, g: int };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=100, g=0};\n"
	  "	s.f /= 4;\n"
	  "	return s.f: i32;\n"
	  "};\n", 25, 0, NULL },
	/* signed /= with a NEGATIVE dividend distinguishes IDIVQ from DIVQ:
	 * -17 / 4 = -4 (CQO+IDIVQ, truncate toward zero); the positive signed
	 * /= above cannot tell IDIVQ from DIVQ. return (-4 + 50) = 46. */
	{ "dotfld_slasheq_neg",
	  "package main;\n"
	  "type S = struct { f: i32, g: i32 };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=-17, g=0};\n"
	  "	s.f /= 4;\n"
	  "	return s.f + 50;\n"
	  "};\n", 46, 0, NULL },
	/* unsigned u32 field /= : 100u32 / 4u32 = 25 (DIVQ + zero-DX). */
	{ "dotfld_slasheq_unsigned",
	  "package main;\n"
	  "type S = struct { f: u32, g: u32 };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=100u32, g=0u32};\n"
	  "	s.f /= 4u32;\n"
	  "	return s.f: i32;\n"
	  "};\n", 25, 0, NULL },
	/* signed %= : 17 % 5 = 2 (result rides DX, MOVQ DX,AX). */
	{ "dotfld_percenteq",
	  "package main;\n"
	  "type S = struct { f: int, g: int };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=17, g=0};\n"
	  "	s.f %= 5;\n"
	  "	return s.f: i32;\n"
	  "};\n", 2, 0, NULL },
	/* <<= : 3 << 4 = 48 (count swapped into CX, value into AX, SHLQ). */
	{ "dotfld_lshifteq",
	  "package main;\n"
	  "type S = struct { f: int, g: int };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=3, g=0};\n"
	  "	s.f <<= 4;\n"
	  "	return s.f: i32;\n"
	  "};\n", 48, 0, NULL },
	/* signed >>= on a NEGATIVE i32 field: -16 >> 2 = -4 ARITHMETIC
	 * (SARQ). return (-4 + 50) = 46 distinguishes from a logical shift. */
	{ "dotfld_rshifteq_neg",
	  "package main;\n"
	  "type S = struct { f: i32, g: i32 };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=-16, g=0};\n"
	  "	s.f >>= 2;\n"
	  "	return s.f + 50;\n"
	  "};\n", 46, 0, NULL },
	/* unsigned u32 field >>= : 200u32 >> 2 = 50 (SHRQ). */
	{ "dotfld_rshifteq_unsigned",
	  "package main;\n"
	  "type S = struct { f: u32, g: u32 };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=200u32, g=0u32};\n"
	  "	s.f >>= 2u32;\n"
	  "	return s.f: i32;\n"
	  "};\n", 50, 0, NULL },
	/* via-ptr base (`p.f` where p is *S fn param): the arm derefs the
	 * pointer before the field load/store. 4 * 3 = 12. */
	{ "dotfld_viaptr_stareq",
	  "package main;\n"
	  "type S = struct { f: int, g: int };\n"
	  "fn bump(p: *S) void = { p.f *= 3; };\n"
	  "export fn main() i32 = {\n"
	  "	let a: S = S{f=4, g=0};\n"
	  "	bump(&a);\n"
	  "	return a.f: i32;\n"
	  "};\n", 12, 0, NULL },
	/* global struct field: gs.f /= 4 → 5 (LEAQ gs(SB) base). */
	{ "dotfld_global_slasheq",
	  "package main;\n"
	  "type S = struct { f: int, g: int };\n"
	  "let gs: S = S{f=20, g=0};\n"
	  "export fn main() i32 = {\n"
	  "	gs.f /= 4;\n"
	  "	return gs.f: i32;\n"
	  "};\n", 5, 0, NULL },
	/* str/slice pseudo-field compound (`sl.len -= 3`): the pseudo-field
	 * arm (delta = 8 for .len) must combine, not store the rhs. 8-3 = 5. */
	{ "dotfld_pseudo_len_minuseq",
	  "package main;\n"
	  "export fn main() i32 = {\n"
	  "	let buf: [8]u8 = [1u8,2u8,3u8,4u8,5u8,6u8,7u8,8u8];\n"
	  "	let sl: []u8 = buf[0:8];\n"
	  "	sl.len -= 3;\n"
	  "	return sl.len: i32;\n"
	  "};\n", 5, 0, NULL },
	/* pseudo-field *= (the silently-demoted op): 4 * 3 = 12. */
	{ "dotfld_pseudo_len_stareq",
	  "package main;\n"
	  "export fn main() i32 = {\n"
	  "	let buf: [8]u8 = [1u8,2u8,3u8,4u8,5u8,6u8,7u8,8u8];\n"
	  "	let sl: []u8 = buf[0:4];\n"
	  "	sl.len *= 3;\n"
	  "	return sl.len: i32;\n"
	  "};\n", 12, 0, NULL },
	/* Plain `s.f = v` control: ASSIGN path byte-id unchanged. */
	{ "dotfld_plain_assign_ctrl",
	  "package main;\n"
	  "type S = struct { f: int, g: int };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=1, g=0};\n"
	  "	s.f = 99;\n"
	  "	return s.f: i32;\n"
	  "};\n", 99, 0, NULL },
	/* HARD-ERROR rows (#34/rule-7): float/str/slice/tagged FIELD compound
	 * builds MUST FAIL LOUD on both stages with the cited diagnostic. */
	{ "dotfld_he_float",
	  "package main;\n"
	  "type S = struct { f: f64, g: int };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=1.0, g=0};\n"
	  "	s.f *= 2.0;\n"
	  "	return 0;\n"
	  "};\n", 0, 1, "single-dot field compound on float field" },
	{ "dotfld_he_str",
	  "package main;\n"
	  "type S = struct { f: str, g: int };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=\"a\", g=0};\n"
	  "	s.f += \"x\";\n"
	  "	return 0;\n"
	  "};\n", 0, 1, "single-dot field compound on str field" },
	{ "dotfld_he_slice",
	  "package main;\n"
	  "type S = struct { f: []u8, g: int };\n"
	  "export fn main() i32 = {\n"
	  "	let b: [2]u8 = [1u8, 2u8];\n"
	  "	let s: S = S{f=b[0:2], g=0};\n"
	  "	s.f += b[0:1];\n"
	  "	return 0;\n"
	  "};\n", 0, 1, "single-dot field compound on slice field" },
	{ "dotfld_he_tagged",
	  "package main;\n"
	  "type S = struct { f: (i32|str), g: int };\n"
	  "export fn main() i32 = {\n"
	  "	let s: S = S{f=1, g=0};\n"
	  "	s.f += 3;\n"
	  "	return 0;\n"
	  "};\n", 0, 1, "single-dot field compound on tagged field" },
	{ NULL, NULL, 0, 0, NULL }
};

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

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 w6c[1100], w6c_ww[1100];
	snprintf(w6c, sizeof w6c, "%s/w6c", bin);
	snprintf(w6c_ww, sizeof w6c_ww, "%s/w6c_ww", bin);
	if (access(w6c_ww, X_OK) != 0) {
		fprintf(stderr, "idxcompound: w6c_ww missing — cannot run the "
		    "cs==ww byte-id gate (the whole point of this test)\n");
		return 1;
	}

	int n = 0, fail = 0;
	for (int i = 0; rows[i].src; i++, n++) {
		char src[64];
		snprintf(src, sizeof src, "/tmp/wwidx_%d_%d.ww", getpid(), i);
		FILE *f = fopen(src, "wb");
		if (f == NULL) { fail++; continue; }
		fputs(rows[i].src, f);
		fclose(f);

		/* (a) cstage build + run, OR build-must-fail (builderr rows).
		 * For builderr: stderr captured to a temp file; pass iff
		 * exit-nonzero AND stderr contains experr substring. */
		char tmpdir[64];
		snprintf(tmpdir, sizeof tmpdir, "/tmp/wwidx_%d_d_%d",
		    getpid(), i);
		mkdir(tmpdir, 0755);

		char cmd[2048];
		if (rows[i].builderr) {
			char errf[96];
			snprintf(errf, sizeof errf, "/tmp/wwidx_%d_e_%d",
			    getpid(), i);
			snprintf(cmd, sizeof cmd,
			    "cd %s && %s/ww build %s >/dev/null 2>%s",
			    tmpdir, bin, src, errf);
			int brc = runwait(cmd);
			FILE *ef = fopen(errf, "rb");
			char ebuf[4096];
			size_t en = 0;
			if (ef) { en = fread(ebuf, 1, sizeof ebuf - 1, ef);
			    fclose(ef); }
			ebuf[en] = '\0';
			int ok = (brc != 0)
			    && (rows[i].experr == NULL
			        || strstr(ebuf, rows[i].experr) != NULL);
			if (!ok) {
				fprintf(stderr, "row[%s]: cstage expected "
				    "builderr+'%s' (brc=%d, stderr='%s')\n",
				    rows[i].label,
				    rows[i].experr ? rows[i].experr : "(any)",
				    brc, ebuf);
				fail++;
			}

			/* Also verify wwstage hard-errors with the SAME message
			 * (rule-10 — both stages identical diagnostic). Invoke
			 * w6c_ww directly on the .ww source. */
			snprintf(cmd, sizeof cmd,
			    "%s -o /dev/null %s >/dev/null 2>%s",
			    w6c_ww, src, errf);
			int wrc = runwait(cmd);
			ef = fopen(errf, "rb"); en = 0;
			if (ef) { en = fread(ebuf, 1, sizeof ebuf - 1, ef);
			    fclose(ef); }
			ebuf[en] = '\0';
			int wok = (wrc != 0)
			    && (rows[i].experr == NULL
			        || strstr(ebuf, rows[i].experr) != NULL);
			if (!wok) {
				fprintf(stderr, "row[%s]: wwstage expected "
				    "builderr+'%s' (wrc=%d, stderr='%s')\n",
				    rows[i].label,
				    rows[i].experr ? rows[i].experr : "(any)",
				    wrc, ebuf);
				fail++;
			}
			unlink(errf);
			unlink(src); rmdir(tmpdir);
			continue;
		}

		snprintf(cmd, sizeof cmd, "cd %s && %s/ww build %s",
		    tmpdir, bin, src);
		if (runwait(cmd) != 0) {
			fprintf(stderr, "row[%s]: cstage build failed\n",
			    rows[i].label);
			fail++;
			unlink(src); rmdir(tmpdir);
			continue;
		}

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

		int got = runwait(outbin);
		if (got != rows[i].want_exit) {
			fprintf(stderr, "row[%s]: cstage exit %d, want %d\n",
			    rows[i].label, got, rows[i].want_exit);
			fail++;
		}
		unlink(outbin); rmdir(tmpdir);

		/* (b) cs==ww byte-id gate. */
		char cs_s[64], ws_s[64];
		snprintf(cs_s, sizeof cs_s, "/tmp/wwidx_%d_%d_cs.s",
		    getpid(), i);
		snprintf(ws_s, sizeof ws_s, "/tmp/wwidx_%d_%d_ww.s",
		    getpid(), i);

		snprintf(cmd, sizeof cmd, "%s -o %s %s 2>/dev/null",
		    w6c, cs_s, src);
		if (runwait(cmd) != 0) {
			fprintf(stderr, "row[%s]: w6c failed\n", rows[i].label);
			fail++; unlink(src); continue;
		}
		snprintf(cmd, sizeof cmd, "%s -o %s %s 2>/dev/null",
		    w6c_ww, ws_s, src);
		if (runwait(cmd) != 0) {
			fprintf(stderr, "row[%s]: w6c_ww failed\n",
			    rows[i].label);
			fail++; unlink(src); unlink(cs_s); continue;
		}
		if (slurp_eq(cs_s, ws_s) != 0) {
			fprintf(stderr,
			    "row[%s]: cstage/wwstage .s DIFFER (rule-10 "
			    "byte-id violation)\n", rows[i].label);
			fail++;
		}
		unlink(src); unlink(cs_s); unlink(ws_s);
	}

	if (fail) {
		fprintf(stderr, "%d/%d dotfield-compound tests failed\n",
		    fail, n);
		return 1;
	}
	printf("dotfield-compound: %d/%d ok (cstage run + cs==ww byte-id)\n",
	    n, n);
	return 0;
}