/*
 * 780_fmt_vstream_mods_run — project #94 fold-e6 sentinel. Pins the
 * V-side modifier-formatting machinery (vrawleni64 / vrawlenstr /
 * vrawlenf64 / vrawlen / vformatraw / vformatone) in lib/fmt/
 * vstream.ww. Before fold-e6, the V printf path parsed mods via
 * scanmods but dropped them after parse: vformatfield routed straight
 * to vwriteone (no width / alignment / pad / sign / base / prec
 * honoured). fold-e6 widens vformatfield to take `*mods` and routes
 * through vformatone — same dispatch shape as OLD formatfield at
 * fmt.ww:648. Coexists with the OLD modifier path at fmt.ww:443-641
 * (fmt.ww UNCHANGED this fold); fold-eFinal (task #50) collapses both
 * surfaces.
 *
 * Each row imports fmt + os + io, opens a per-process /tmp output
 * file, calls fdprintf_v with a {:mods} format string + one arg, and
 * asserts the exact byte content read back.
 *
 * Cstage-only per row — pre-existing wwstage bug #209 (sibling of
 * #190): the wwstage checker bails on fmt.formattable match-arms
 * whenever a downstream probe `import fmt;`s the package. Identical
 * carve-out to 777_fmt_vstream_run (cited there at line 18-33).
 * Byte-id graduates with #209 close.
 *
 *   row              | format     | arg          | expect    | exit
 *   -----------------+------------+--------------+-----------+-----
 *   width            | "{:5}"     | 42i64        | "   42"   | 50
 *   precision        | "{:.3}"    | "hello"      | "hel"     | 51
 *   base_hex         | "{:x}"     | 255i64       | "ff"      | 52
 *   sign_plus        | "{:+}"     | 7i64         | "+7"      | 53
 *   zero_pad         | "{:_05}"   | 42i64        | "00042"   | 54
 *
 * Modifier surface exercised (subset of scanmods at fmt.ww:376-405):
 *
 *   width    digits 1..9 — RIGHT-align pad to N chars
 *   prec     '.' + digits — str truncation / int min-digits
 *   base     'x' — strconv.base.HEX_LOWER
 *   neg      '+' — emit '+' on non-negative
 *   pad      '_<rune>' — pad rune override (default space when ':')
 *
 * Drew NaN/Inf signoff (carry from task #58): f64 arm not exercised
 * here (rows pin i64+str+bool fastpaths); follow-on fold can add f64
 * once Drew's strconv.f64tos shortest-G stays static. The fold-e6
 * implementation honours the sign-peel in vformatraw f64 arm; an
 * end-to-end test lands when a NaN/Inf-aware probe joins the corpus.
 *
 * IMPORT-ORDER WORKAROUND (sibling task #208, pre-existing): every
 * row places `import os;` FIRST for the same reason 776/777 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-e6 is purely additive
 * over fold-e1/e2/e3/e4/e5's frozen io.* + memio.* + fmt.* + bufio.*
 * + log.* surface):
 *
 *   - #209 (wwstage formattable match-arm bail): blocks STAGE_WW
 *     here, same as 777_fmt_vstream_run. Cstage-only until close.
 *   - eFinal (#50): collapses V + OLD surfaces; the `v*` names rename
 *     off and the OLD rawlen* / formatraw / formatone delete. The v*
 *     duplication of the rawlen-family today is transient — eFinal
 *     dedupes.
 *
 * BOOTSTRAP-EMBED CHECK: fmt is NOT embedded in any selfhost
 * combined.ww (grep confirmed pre-impl). Adding modifier formatting
 * to lib/fmt/vstream.ww does NOT require a Makefile regen (#110);
 * only test paths see the new machinery. 990-997 byte-id gates stay
 * green by virtue of fmt being test-only on the bootstrap surface.
 *
 * GATE POLARITY: must stay GREEN. A red here means vformatone /
 * vformatraw / vrawlen miscomputed bytes, vformatfield regressed its
 * *mods route, scanmods/modsinit (shared from fmt.ww) drifted, or
 * the strconv.u64tos base path miscompiled under fdprintf_v's
 * intrusive vstream→*fd_ctx dispatch.
 */
#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[] = {
	{ "width",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let path: str = \"/tmp/wwfmtv_780_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.fdprintf_v(fd, \"{:5}\", 42i64);\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 != 5i64) { return 93; };\n"
	  "    if (nw != 5: size) { return 94; };\n"
	  "    if (buf[0] != 32u8 || buf[1] != 32u8 || buf[2] != 32u8 || buf[3] != 52u8 || buf[4] != 50u8) { return 95; };\n"
	  "    return 50;\n"
	  "};\n",
	  50,
	  STAGE_CS, 0 },
	{ "precision",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let path: str = \"/tmp/wwfmtv_780_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.fdprintf_v(fd, \"{:.3}\", \"hello\");\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 != 3i64) { return 93; };\n"
	  "    if (nw != 3: size) { return 94; };\n"
	  "    if (buf[0] != 104u8 || buf[1] != 101u8 || buf[2] != 108u8) { return 95; };\n"
	  "    return 51;\n"
	  "};\n",
	  51,
	  STAGE_CS, 0 },
	{ "base_hex",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let path: str = \"/tmp/wwfmtv_780_c\";\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.fdprintf_v(fd, \"{:x}\", 255i64);\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 != 2i64) { return 93; };\n"
	  "    if (nw != 2: size) { return 94; };\n"
	  "    if (buf[0] != 102u8 || buf[1] != 102u8) { return 95; };\n"
	  "    return 52;\n"
	  "};\n",
	  52,
	  STAGE_CS, 0 },
	{ "sign_plus",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let path: str = \"/tmp/wwfmtv_780_d\";\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.fdprintf_v(fd, \"{:+}\", 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 != 2i64) { return 93; };\n"
	  "    if (nw != 2: size) { return 94; };\n"
	  "    if (buf[0] != 43u8 || buf[1] != 55u8) { return 95; };\n"
	  "    return 53;\n"
	  "};\n",
	  53,
	  STAGE_CS, 0 },
	{ "zero_pad",
	  "package main;\n"
	  "import os;\n"
	  "import fmt;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let path: str = \"/tmp/wwfmtv_780_e\";\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.fdprintf_v(fd, \"{:_05}\", 42i64);\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 != 5i64) { return 93; };\n"
	  "    if (nw != 5: size) { return 94; };\n"
	  "    if (buf[0] != 48u8 || buf[1] != 48u8 || buf[2] != 48u8 || buf[3] != 52u8 || buf[4] != 50u8) { return 95; };\n"
	  "    return 54;\n"
	  "};\n",
	  54,
	  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 (filed task #15), so each row's build leaves
 * <src>.{combined.ww,s,o} + bare exe alongside. Mirror of 777'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/fvm_%d_d_%d", getpid(), seq);
	snprintf(base,   sizeof base,   "main780");
	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_mods_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_mods_run[ww][%s]: exit=%d want=%d\n",
				    rows[i].label, got, rows[i].want_exit);
				fail++;
			}
		}
	}

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

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