/*
 * 781_fmt_compositions_run — io fold-2 (#5) commit-2 sentinel. Pins the
 * composition wrappers in lib/fmt/fmt.ww — fprintln / fprintfln /
 * bsprintf / asprintf — plus the memio accessor (memio.string in
 * lib/memio/memio.ww) they read back through. #5 graduated the
 * fprint-family sink io.stream -> io.handle; the file-arm rows drive
 * fprintln / fprintfln over `fd: io.file`, the stream-arm rows over a
 * memio.fixed io.stream — both arms of io.handle.
 *
 * memio.string is the direct enabler: bsprintf reads its written prefix
 * via memio.string; asprintf reads its grown buffer via the same
 * accessor.
 *
 *   row                 | what it pins
 *   --------------------+--------------------------------------
 *   fprintln_file_basic | fprintln(fd: io.file, 1, "hi", true)
 *                       | over the file arm — space-separator plus
 *                       | trailing newline byte content.
 *   fprintfln_file_fmt  | fprintfln(fd: io.file, "x={}", 7) over the
 *                       | file arm — placeholder substitution +
 *                       | trailing newline.
 *   fprintln_basic      | fmt.fprintln dispatched over a memio.fixed
 *                       | io.stream (stream arm) + read back via
 *                       | memio.string. Pins the composition symbol.
 *   fprintfln_basic     | fmt.fprintfln over memio.fixed + memio.string,
 *                       | same stream-arm rationale.
 *   bsprintf_basic      | bsprintf into a caller-supplied [16]u8
 *                       | buffer through memio.fixed; memio.string
 *                       | returns the prefix view. Asserts both the
 *                       | caller-buffer bytes AND the returned str view.
 *   asprintf_basic      | asprintf into a heap-grown str through
 *                       | memio.dynamic; memio.string + shrink-copy +
 *                       | io.close. Asserts the owned str bytes, then
 *                       | frees via os.free.
 *
 * Cstage-only per row (no STAGE_WW, no byte_id). #209 (the wwstage
 * checker bail `case: not a variant of scrutinee` + `match: variant not
 * handled (formattable)` on fmt's spread-union match-arms) is now CLOSED;
 * wwstage compiles fmt. The residual blocker is the pre-existing cgen
 * cluster #226 (io.read error-remap nominal-identity) + #227 (spread-union
 * widen/return-ABI). Identical carve-out to 777_fmt_handle_run +
 * 780_fmt_mods_run. Byte-id graduates when #226 (+#227) land.
 *
 * IMPORT-ORDER WORKAROUND (sibling task #208, pre-existing): every row
 * places `import os;` FIRST for the same reason 776/777/780 document
 * (wwstage checker ordering-sensitivity on os.tryread / trywrite /
 * tryopen's bare `return r;` over a tagged return type).
 *
 * DEFERRALS / RELATED (NOT addressed by these rows):
 *
 *   - #226 (io.read error-remap nominal-identity) + #227 (spread-union
 *     widen/return-ABI): block STAGE_WW here, same as 777/780. #209 (the
 *     checker bail) is closed; these cgen folds are the residual.
 *     Cstage-only until they land.
 *   - #173 (TRY-on-tagged-return both-stages broken): bsprintf widens
 *     nomem into io.error inline rather than `memio.fixed(buf)?` for
 *     the same reason memio.ww does.
 *
 * BOOTSTRAP-EMBED CHECK: fmt is NOT embedded in any selfhost
 * combined.ww (grep verified). memio IS embedded in w6c + wwdump
 * combined.ww but is unchanged by #5, so no regen rides along here.
 * 990/994/995 byte-id gates stay green.
 *
 * GATE POLARITY: must stay GREEN. A red here means fprintln /
 * fprintfln dropped the newline byte, bsprintf returned a stale
 * memio.string view (intrusive cast broke), asprintf failed to
 * shrink-copy / close cleanly, or the underlying fprint / fprintf
 * primitives regressed over the io.handle sink.
 */
#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;
}

#define STAGE_CS	1
#define STAGE_WW	2

struct row {
	const char *label;
	const char *src;
	int want_exit;
	int stage_mask;
	int byte_id;
};

static const struct row rows[] = {
	{ "fprintln_file_basic",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let path: str = \"/tmp/wwfmtc_781_a\";\n"
	  "    let fd: i32 = os.open(path, os.flag.RDWR | os.flag.CREATE | os.flag.TRUNC, 0o644: i32);\n"
	  "    if (fd < 0) { return 90; };\n"
	  "    let wr = fmt.fprintln(fd: io.file, 1i64, \"hi\", true);\n"
	  "    let nw: size = 0;\n"
	  "    match (wr) {\n"
	  "    case let n: size => { nw = n; };\n"
	  "    case io.error => { return 91; };\n"
	  "    };\n"
	  "    os.close(fd);\n"
	  "    let rd: i32 = os.open(path, os.flag.RDONLY, 0i32);\n"
	  "    if (rd < 0) { return 92; };\n"
	  "    let buf: [16]u8;\n"
	  "    let n: i64 = os.read(rd, &buf[0], 16u64);\n"
	  "    os.close(rd);\n"
	  "    if (n != 10i64) { return 93; };\n"
	  "    if (nw != 10: size) { return 94; };\n"
	  "    if (buf[0] != 49u8) { return 95; };\n"
	  "    if (buf[1] != 32u8) { return 96; };\n"
	  "    if (buf[2] != 104u8 || buf[3] != 105u8) { return 97; };\n"
	  "    if (buf[4] != 32u8) { return 98; };\n"
	  "    if (buf[9] != 10u8) { return 99; };\n"
	  "    return 60;\n"
	  "};\n",
	  60,
	  STAGE_CS | STAGE_WW, 1 },
	{ "fprintfln_file_fmt",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let path: str = \"/tmp/wwfmtc_781_b\";\n"
	  "    let fd: i32 = os.open(path, os.flag.RDWR | os.flag.CREATE | os.flag.TRUNC, 0o644: i32);\n"
	  "    if (fd < 0) { return 90; };\n"
	  "    let wr = fmt.fprintfln(fd: io.file, \"x={}\", 7i64);\n"
	  "    let nw: size = 0;\n"
	  "    match (wr) {\n"
	  "    case let n: size => { nw = n; };\n"
	  "    case io.error => { return 91; };\n"
	  "    };\n"
	  "    os.close(fd);\n"
	  "    let rd: i32 = os.open(path, os.flag.RDONLY, 0i32);\n"
	  "    if (rd < 0) { return 92; };\n"
	  "    let buf: [16]u8;\n"
	  "    let n: i64 = os.read(rd, &buf[0], 16u64);\n"
	  "    os.close(rd);\n"
	  "    if (n != 4i64) { return 93; };\n"
	  "    if (nw != 4: size) { return 94; };\n"
	  "    if (buf[0] != 120u8 || buf[1] != 61u8 || buf[2] != 55u8 || buf[3] != 10u8) { return 95; };\n"
	  "    return 61;\n"
	  "};\n",
	  61,
	  STAGE_CS | STAGE_WW, 1 },
	{ "fprintln_basic",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "import memio;\n"
	  "export fn main() i32 = {\n"
	  "    let buf: [16]u8;\n"
	  "    let st: memio.stream = memio.fixed(buf[0:16]);\n"
	  "    let vs: io.stream = &st.vt;\n"
	  "    let wr = fmt.fprintln(vs, 1i64, \"hi\", true);\n"
	  "    let nw: size = 0;\n"
	  "    match (wr) {\n"
	  "    case let n: size => { nw = n; };\n"
	  "    case io.error => { return 91; };\n"
	  "    };\n"
	  "    if (nw != 10: size) { return 92; };\n"
	  "    let view: str = memio.string(&st);\n"
	  "    if (view.len != 10) { return 93; };\n"
	  "    if (view[0] != 49u8) { return 94; };\n"
	  "    if (view[1] != 32u8) { return 95; };\n"
	  "    if (view[2] != 104u8 || view[3] != 105u8) { return 96; };\n"
	  "    if (view[9] != 10u8) { return 97; };\n"
	  "    return 64;\n"
	  "};\n",
	  64,
	  STAGE_CS | STAGE_WW, 1 },
	{ "fprintfln_basic",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "import memio;\n"
	  "export fn main() i32 = {\n"
	  "    let buf: [16]u8;\n"
	  "    let st: memio.stream = memio.fixed(buf[0:16]);\n"
	  "    let vs: io.stream = &st.vt;\n"
	  "    let wr = fmt.fprintfln(vs, \"x={}\", 7i64);\n"
	  "    let nw: size = 0;\n"
	  "    match (wr) {\n"
	  "    case let n: size => { nw = n; };\n"
	  "    case io.error => { return 91; };\n"
	  "    };\n"
	  "    if (nw != 4: size) { return 92; };\n"
	  "    let view: str = memio.string(&st);\n"
	  "    if (view.len != 4) { return 93; };\n"
	  "    if (view[0] != 120u8 || view[1] != 61u8) { return 94; };\n"
	  "    if (view[2] != 55u8 || view[3] != 10u8) { return 95; };\n"
	  "    return 65;\n"
	  "};\n",
	  65,
	  STAGE_CS | STAGE_WW, 1 },
	{ "bsprintf_basic",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let buf: [16]u8;\n"
	  "    let r = fmt.bsprintf(buf[0:16], \"v={}\", 42i64);\n"
	  "    let view: str = \"\";\n"
	  "    match (r) {\n"
	  "    case let s: str => { view = s; };\n"
	  "    case io.error => { return 90; };\n"
	  "    };\n"
	  "    if (view.len != 4) { return 91; };\n"
	  "    if (view[0] != 118u8 || view[1] != 61u8) { return 92; };\n"
	  "    if (view[2] != 52u8 || view[3] != 50u8) { return 93; };\n"
	  "    if (buf[0] != 118u8 || buf[3] != 50u8) { return 94; };\n"
	  "    return 62;\n"
	  "};\n",
	  62,
	  STAGE_CS | STAGE_WW, 1 },
	{ "asprintf_basic",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let view: str = fmt.asprintf(\"hello={}\", 9i64);\n"
	  "    if (view.len != 7) { return 90; };\n"
	  "    if (view[0] != 104u8 || view[1] != 101u8 || view[2] != 108u8) { return 91; };\n"
	  "    if (view[3] != 108u8 || view[4] != 111u8) { return 92; };\n"
	  "    if (view[5] != 61u8 || view[6] != 57u8) { return 93; };\n"
	  "    os.free(view.ptr: *void, view.len: u64);\n"
	  "    return 63;\n"
	  "};\n",
	  63,
	  STAGE_CS | STAGE_WW, 1 },
};

static int
write_source(const char *path, const char *src)
{
	FILE *f = fopen(path, "wb");
	if (!f) return -1;
	fputs(src, f);
	fclose(f);
	return 0;
}

/* Per-row tmpdir cleanup. ww_ww writes intermediates next to the
 * source (task #15), so each row's build leaves <src>.{combined.ww,
 * s,o} + bare exe alongside. Mirror of 777/780's. */
static void
cleanup_tmp(const char *tmpdir, const char *base)
{
	char p[640];
	snprintf(p, sizeof p, "%s/%s.ww", tmpdir, base); unlink(p);
	snprintf(p, sizeof p, "%s/%s.s",  tmpdir, base); unlink(p);
	snprintf(p, sizeof p, "%s/%s.o",  tmpdir, base); unlink(p);
	snprintf(p, sizeof p, "%s/%s.combined.ww", tmpdir, base); unlink(p);
	snprintf(p, sizeof p, "%s/%s",    tmpdir, base); unlink(p);
	rmdir(tmpdir);
}

static int
build_via_driver(const char *driver, const char *tmpdir, const char *cwd,
    const char *src)
{
	char cmd[2048];
	snprintf(cmd, sizeof cmd,
	    "cd %s && timeout 180 %s build -I %s/lib %s 2>/dev/null",
	    tmpdir, driver, cwd, src);
	return runwait(cmd);
}

static int
run_row(const char *driver, const char *cwd, const struct row *r, int seq)
{
	char tmpdir[256], src[512], base[64], outbin[768];
	snprintf(tmpdir, sizeof tmpdir, "/tmp/fhc_%d_d_%d", getpid(), seq);
	snprintf(base,   sizeof base,   "main781");
	snprintf(src,    sizeof src,    "%s/%s.ww", tmpdir, base);
	mkdir(tmpdir, 0755);
	if (write_source(src, r->src) != 0) { cleanup_tmp(tmpdir, base); return -1; }
	int rc;
	int br = build_via_driver(driver, tmpdir, cwd, src);
	if (br == 0) {
		snprintf(outbin, sizeof outbin, "%s/%s", tmpdir, base);
		rc = runwait(outbin);
	} else {
		rc = -1;
	}
	cleanup_tmp(tmpdir, base);
	return rc;
}

int
main(void)
{
	const char *bin = getenv("BIN");
	if (!bin) bin = "out/bin";
	char cwd[256];
	if (getcwd(cwd, sizeof cwd) == NULL) return 1;
	char absbin[512];
	if (bin[0] != '/') {
		snprintf(absbin, sizeof absbin, "%s/%s", cwd, bin);
		bin = absbin;
	}

	char cdrv[640], wdrv[640];
	snprintf(cdrv, sizeof cdrv, "%s/ww",    bin);
	snprintf(wdrv, sizeof wdrv, "%s/ww_ww", bin);

	int n = (int)(sizeof rows / sizeof rows[0]);
	int total = 0, fail = 0;
	int wwpresent = (access(wdrv, X_OK) == 0);
	int seq = 0;

	for (int i = 0; i < n; i++) {
		if (rows[i].stage_mask & STAGE_CS) {
			total++;
			int got = run_row(cdrv, cwd, &rows[i], seq++);
			if (got != rows[i].want_exit) {
				fprintf(stderr,
				    "fmt_compositions_run[cs][%s]: exit=%d want=%d\n",
				    rows[i].label, got, rows[i].want_exit);
				fail++;
			}
		}
		if (wwpresent && (rows[i].stage_mask & STAGE_WW)) {
			total++;
			int got = run_row(wdrv, cwd, &rows[i], seq++);
			if (got != rows[i].want_exit) {
				fprintf(stderr,
				    "fmt_compositions_run[ww][%s]: exit=%d want=%d\n",
				    rows[i].label, got, rows[i].want_exit);
				fail++;
			}
		}
	}

	if (!wwpresent)
		fprintf(stderr, "fmt_compositions_run: skip wwstage (no %s)\n", wdrv);

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