/*
 * 781_fmt_vstream_compositions_run — project #94 fold-e7 sentinel.
 * Pins the V-side composition wrappers in lib/fmt/vstream.ww —
 * vfprintln / vfprintfln / vbsprintf / vasprintf — plus the two
 * memio enablers fold-e7 bundles alongside (memio.fixed_string /
 * memio.dynamic_string in lib/memio/vstream.ww). Coexists with the
 * OLD fmt.fprintln / fprintfln / bsprintf / asprintf surface in
 * fmt.ww:240,740,839,873 (fmt.ww UNCHANGED this fold; eFinal
 * task #50 collapses both surfaces and renames the `v` suffix off).
 *
 * The two memio helpers are direct enablers (vbsprintf reads its
 * written prefix via fixed_string; vasprintf reads its grown buffer
 * via dynamic_string), drew-approved per
 * feedback_refactor_routing_same_class_drops (prereqs, not churn).
 *
 * Each row imports fmt + os + io, drives one of the four V wrappers,
 * and asserts the exact bytes / size emitted. Per-row unique exit
 * constant lets a failure pinpoint the offending case.
 *
 *   row                       | what it pins
 *   --------------------------+--------------------------------------
 *   fdprintln_v_run_basic     | fdprintln_v wired vstream sink
 *                             | (inline vfprint + vputbytes "\n").
 *                             | One i64 arg + str arg + bool arg;
 *                             | asserts space-separator plus trailing
 *                             | newline byte content.
 *   fdprintfln_v_run_fmt      | fdprintfln_v wired vstream sink with
 *                             | a {n}-placeholder format string.
 *                             | Asserts placeholder substitution +
 *                             | trailing newline shape (mirror of
 *                             | fmt.fprintfln, fmt.ww:740).
 *   vfprintln_basic           | fmt.vfprintln dispatched DIRECTLY
 *                             | through memio.fixed_vstream + read
 *                             | back via memio.fixed_string. Pins
 *                             | the new V-side composition symbol
 *                             | itself (fdprintln_v open-codes the
 *                             | same vfprint+vputbytes chain rather
 *                             | than calling vfprintln, so without
 *                             | this row the new symbol ships
 *                             | uncovered).
 *   vfprintfln_basic          | fmt.vfprintfln direct dispatch via
 *                             | memio.fixed_vstream + fixed_string,
 *                             | same direct-symbol rationale as
 *                             | vfprintln_basic.
 *   bsprintf_v_basic          | vbsprintf into a caller-supplied
 *                             | [16]u8 buffer through
 *                             | memio.fixed_vstream;
 *                             | memio.fixed_string returns the prefix
 *                             | view. Asserts both the bytes in the
 *                             | caller's buffer AND the returned str
 *                             | view (ptr == buf + 0, len == 5).
 *   asprintf_v_basic          | vasprintf into a heap-grown str
 *                             | through memio.dynamic_vstream;
 *                             | memio.dynamic_string + shrink-copy +
 *                             | io.st_close. Asserts the owned str
 *                             | bytes, then frees via os.free.
 *
 * Cstage-only per row (no STAGE_WW, no byte_id) — pre-existing
 * wwstage bug #209 (sibling of #190): the wwstage checker bails
 * `case: not a variant of scrutinee (X)` + `match: variant not
 * handled (formattable)` on fmt.formattable match-arms whenever a
 * downstream probe `import fmt;`s the package. Identical carve-out
 * to 777_fmt_vstream_run + 780_fmt_vstream_mods_run (cited there at
 * line 18-33 / 18-23). Byte-id graduates with #209 close.
 *
 * 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).
 *
 * SIBLINGS (filed inline, NOT fixed here — fold-e7 is purely
 * additive over fold-e1/e2/e3/e4/e5/e6's frozen io.* + memio.* +
 * fmt.* + bufio.* + log.* surface):
 *
 *   - #209 (wwstage formattable match-arm bail): blocks STAGE_WW
 *     here, same as 777/780. Cstage-only until close.
 *   - #173 (TRY-on-tagged-return both-stages broken): vbsprintf
 *     widens nomem into io.error inline rather than `memio.
 *     fixed_vstream(buf)?` for the same reason memio.vstream.ww
 *     does at line 87-99.
 *   - eFinal (#50): collapses V + OLD surfaces; the `v` names
 *     rename off and the OLD fprintln / fprintfln / bsprintf /
 *     asprintf delete.
 *
 * BOOTSTRAP-EMBED CHECK: fmt is NOT embedded in any selfhost
 * combined.ww (grep verified pre-impl). memio.vstream.ww IS embedded
 * in w6c + wwdump combined.ww — the fold-e7 memio helpers ride along
 * via the regen committed in this same commit (per #110 SSoT). 990/
 * 994/995 byte-id gates + combined_ww_fresh stay green by virtue of
 * the regen.
 *
 * GATE POLARITY: must stay GREEN. A red here means vfprintln /
 * vfprintfln dropped the newline byte, vbsprintf returned a stale
 * memio.fixed_string view (intrusive cast broke), vasprintf failed
 * to shrink-copy / close cleanly, or the underlying vfprint /
 * vfprintf primitives regressed.
 */
#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[] = {
	{ "fdprintln_v_run_basic",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let path: str = \"/tmp/wwfmtv_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.fdprintln_v(fd, 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, 0 },
	{ "fdprintfln_v_run_fmt",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let path: str = \"/tmp/wwfmtv_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.fdprintfln_v(fd, \"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, 0 },
	{ "vfprintln_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 r: (io.vstream | nomem) = memio.fixed_vstream(buf[0:16]);\n"
	  "    let vs: io.vstream = nil: *io.vtable;\n"
	  "    match (r) {\n"
	  "    case let v: io.vstream => { vs = v; };\n"
	  "    case nomem => { return 90; };\n"
	  "    };\n"
	  "    let wr = fmt.vfprintln(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.fixed_string(vs);\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, 0 },
	{ "vfprintfln_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 r: (io.vstream | nomem) = memio.fixed_vstream(buf[0:16]);\n"
	  "    let vs: io.vstream = nil: *io.vtable;\n"
	  "    match (r) {\n"
	  "    case let v: io.vstream => { vs = v; };\n"
	  "    case nomem => { return 90; };\n"
	  "    };\n"
	  "    let wr = fmt.vfprintfln(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.fixed_string(vs);\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, 0 },
	{ "bsprintf_v_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.vbsprintf(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, 0 },
	{ "asprintf_v_basic",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let view: str = fmt.vasprintf(\"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, 0 },
};

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/fvc_%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_vstream_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_vstream_compositions_run[ww][%s]: exit=%d want=%d\n",
				    rows[i].label, got, rows[i].want_exit);
				fail++;
			}
		}
	}

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

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