/*
 * 779_log_vstream_run — project #94 fold-eFinal sentinel. Pins the
 * single-surface lib/log: module-static stderrsink_ctx_g with
 * `vt: io.vtable` as the first field for the intrusive cast, the 10
 * exported variants of log.ww's surface (new / lprintln / println /
 * lprintfln / printfln / lfatal / fatal / lfatalf / fatalf /
 * setlogger), a logger vtable + stdlogger over an io.stream sink, and
 * lazy ensureinit wiring the stderr default + silent / default /
 * global *logger globals. The fold-eFinal FLIP collapsed the dual
 * surface into this one Hare-shaped surface (bare names, no suffix).
 *
 * Each row imports os + log + memio + io. log itself imports fmt,
 * so the formattable / field types flow through transitively.
 *
 * Cstage-only per row (no STAGE_WW, no byte_id). #209 (the wwstage
 * checker bail on match-arm-over-formattable when fmt is imported
 * transitively — which lib/log does for the logger vtable signatures +
 * the fmt.fprint / fprintf dispatch in stdprintln / stdprintfln) is now
 * CLOSED; wwstage compiles fmt/log. The residual blocker is the
 * pre-existing cgen cluster #226 (io.read error-remap nominal-identity)
 * + #227 (spread-union widen/return-ABI), surfaced once fmt codegens
 * under wwstage. Existing 971 logtest runs the @test fixture under
 * cstage `ww run` only. 995 self-rebuild dodges it because no selfhost
 * cmd imports log transitively. Byte-id graduates when #226 (+#227) land.
 *
 *   row                       | what it pins
 *   --------------------------+--------------------------------------
 *   println_v_default_stderr  | log.println through the [[default]]
 *                             | global, routed to fd 2 via the
 *                             | module-static stderrsink_ctx_g. Asserts
 *                             | ensureinit wires + dispatches without
 *                             | crashing; stderr capture is left to the
 *                             | shell runner. Pins the full chain:
 *                             | println → lprintln(global) →
 *                             | (*logger).println → stdprintln →
 *                             | fmt.fprint + io.write("\n").
 *   printfln_v_default_stderr | Same chain as row 1 but through the
 *                             | format-string slot (printfln →
 *                             | lprintfln(global) → stdprintfln
 *                             | → fmt.fprintf + io.write("\n")).
 *                             | Pins the {n}-placeholder dispatch
 *                             | through vformatfield reaches the
 *                             | default sink.
 *   lprintln_v_custom_sink    | memio.fixed-backed stdlogger;
 *                             | log.new wires the vtable + sink,
 *                             | log.lprintln dispatches "hi" + 7i64
 *                             | through stdprintln. Asserts the
 *                             | exact bytes ("hi 7\n") land in the
 *                             | caller's buffer (fixed borrows
 *                             | the slice, so the bytes are visible
 *                             | back through buf[]).
 *   branched_lprintln       | branched callee per #105: two distinct
 *                             | stdlogger sinks runtime-selected via
 *                             | *logger pointer. lprintln dispatches
 *                             | through the picked sink only; the
 *                             | other stays empty. Catches a constant-
 *                             | fold mistake in the fn-ptr dispatch
 *                             | (mirror of 778's branched_bufio_wrap).
 *
 * DEFERRALS / RELATED (NOT addressed by this row):
 *
 *   - #206 (bare &fn → (*alias|void)): 2 cast sites at ensureinit
 *     in lib/log/log.ww; the explicit casts are KEPT (ken/#214 —
 *     cast-drop is a separate deferred payoff gated on #214).
 *
 *   - #173 (TRY-on-tagged-return both-stages broken): stderrwrite
 *     constructs nomem and widens to io.error explicitly rather than
 *     using `os.trywrite(...)?`; same shape memio.ww + fmt.ww +
 *     bufio.ww adopt.
 *
 *   - #226 (io.read error-remap nominal-identity) + #227 (spread-union
 *     widen/return-ABI): every row is STAGE_CS-only; byte-id deferred
 *     until they land. #209 (the checker bail) is already closed.
 *
 * BOOTSTRAP-EMBED CHECK: log is NOT embedded in any selfhost
 * combined.ww (grep `package log\|import log` returns empty), so the
 * fold-eFinal log collapse does not require a Makefile regen (#110);
 * only lib/log/ + lib/fmt/ test paths see the surface. 990-997
 * byte-id gates stay green by virtue of log being test-only.
 *
 * GATE POLARITY: must stay GREEN. A red here means lib/log
 * regressed, the module-static stderrsink_ctx_g zero-init or chained
 * vt-field assigns regressed, the intrusive io.stream→*stderrsink_ctx
 * cast miscomputed offsets, ensureinit's one-shot guard broke, or
 * the fn-ptr dispatch through logger.println / printfln stopped
 * resolving.
 */
#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[] = {
	{ "println_v_default_stderr",
	  "package main;\n"
	  "import os;\n"
	  "import log;\n"
	  "export fn main() i32 = {\n"
	  "    log.println(\"hello\");\n"
	  "    return 42;\n"
	  "};\n",
	  42,
	  STAGE_CS, 0 },
	{ "printfln_v_default_stderr",
	  "package main;\n"
	  "import os;\n"
	  "import log;\n"
	  "export fn main() i32 = {\n"
	  "    log.printfln(\"v={}\", 7i64);\n"
	  "    return 43;\n"
	  "};\n",
	  43,
	  STAGE_CS, 0 },
	{ "lprintln_v_custom_sink",
	  "package main;\n"
	  "import os;\n"
	  "import log;\n"
	  "import memio;\n"
	  "import io;\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 sl: log.stdlogger = log.new(vs);\n"
	  "    log.lprintln(&sl.logger, \"hi\", 7i64);\n"
	  "    if (buf[0] != 104u8) { return 91; };\n"
	  "    if (buf[1] != 105u8) { return 92; };\n"
	  "    if (buf[2] != 32u8)  { return 93; };\n"
	  "    if (buf[3] != 55u8)  { return 94; };\n"
	  "    if (buf[4] != 10u8)  { return 95; };\n"
	  "    return 44;\n"
	  "};\n",
	  44,
	  STAGE_CS, 0 },
	{ "branched_lprintln",
	  "package main;\n"
	  "import os;\n"
	  "import log;\n"
	  "import memio;\n"
	  "import io;\n"
	  "export fn main() i32 = {\n"
	  "    let bufA: [16]u8;\n"
	  "    let bufB: [16]u8;\n"
	  "    let stA: memio.stream = memio.fixed(bufA[0:16]);\n"
	  "    let vsA: io.stream = &stA.vt;\n"
	  "    let stB: memio.stream = memio.fixed(bufB[0:16]);\n"
	  "    let vsB: io.stream = &stB.vt;\n"
	  "    let slA: log.stdlogger = log.new(vsA);\n"
	  "    let slB: log.stdlogger = log.new(vsB);\n"
	  "    let sel: i32 = 1;\n"
	  "    let chosen: *log.logger = &slA.logger;\n"
	  "    if (sel == 0) { chosen = &slB.logger; };\n"
	  "    log.lprintln(chosen, \"pick\");\n"
	  "    if (bufA[0] != 112u8) { return 91; };\n"
	  "    if (bufA[1] != 105u8) { return 92; };\n"
	  "    if (bufA[2] != 99u8)  { return 93; };\n"
	  "    if (bufA[3] != 107u8) { return 94; };\n"
	  "    if (bufA[4] != 10u8)  { return 95; };\n"
	  "    if (bufB[0] != 0u8)   { return 96; };\n"
	  "    return 45;\n"
	  "};\n",
	  45,
	  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. Sweep all then
 * rmdir. Mirror of 778's cleanup_tmp. */
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/lvs_%d_d_%d", getpid(), seq);
	snprintf(base,   sizeof base,   "main779");
	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);
		/* Suppress stderr for rows 1/2 — the default-sink probes
		 * write through fd 2; don't pollute the test runner's
		 * stderr. */
		char runcmd[1024];
		snprintf(runcmd, sizeof runcmd, "%s 2>/dev/null", outbin);
		rc = runwait(runcmd);
	} else {
		rc = -1;
	}
	cleanup_tmp(tmpdir, base);
	return rc;
}

/* asm_byte_identical — diff cstage vs wwstage .s. Parallel trees so
 * ww_ww writing intermediates next to the source doesn't clobber the
 * cstage .s (CLAUDE.md rule 14 phase split). Mirror of 778's. Unused
 * for fold-e5 — every row is STAGE_CS-only per #226/#227 (#209, the
 * checker bail, is closed) — but kept scaffolded for when those cgen
 * folds land and byte-id graduates. */
static int
asm_byte_identical(const char *cdrv, const char *wdrv, const char *cwd,
    const struct row *r, int seq)
{
	char src[512], tdc[256], tdw[256], base[64], cs[512], ws[512];
	snprintf(tdc, sizeof tdc, "/tmp/lvs_%d_c_%d", getpid(), seq);
	snprintf(tdw, sizeof tdw, "/tmp/lvs_%d_w_%d", getpid(), seq);
	snprintf(base, sizeof base, "main779");
	mkdir(tdc, 0755);
	mkdir(tdw, 0755);
	snprintf(src, sizeof src, "%s/%s.ww", tdc, base);
	if (write_source(src, r->src) != 0) { cleanup_tmp(tdc, base); cleanup_tmp(tdw, base); return -1; }
	int rc = -1;
	if (build_via_driver(cdrv, tdc, cwd, src) != 0) goto out;
	snprintf(cs, sizeof cs, "%s/%s.s", tdc, base);

	snprintf(src, sizeof src, "%s/%s.ww", tdw, base);
	if (write_source(src, r->src) != 0) goto out;
	if (build_via_driver(wdrv, tdw, cwd, src) != 0) goto out;
	snprintf(ws, sizeof ws, "%s/%s.s", tdw, base);

	FILE *fc = fopen(cs, "rb");
	FILE *fw = fopen(ws, "rb");
	if (fc && fw) {
		rc = 0;
		for (;;) {
			int a = fgetc(fc);
			int b = fgetc(fw);
			if (a != b) { rc = -1; break; }
			if (a == EOF) break;
		}
	}
	if (fc) fclose(fc);
	if (fw) fclose(fw);
out:
	cleanup_tmp(tdc, base);
	cleanup_tmp(tdw, 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,
				    "log_vstream_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,
				    "log_vstream_run[ww][%s]: exit=%d want=%d\n",
				    rows[i].label, got, rows[i].want_exit);
				fail++;
			}
			if (rows[i].byte_id) {
				total++;
				if (asm_byte_identical(cdrv, wdrv, cwd, &rows[i], seq++) != 0) {
					fprintf(stderr,
					    "log_vstream_run[byte-id][%s]: cstage vs wwstage asm differs\n",
					    rows[i].label);
					fail++;
				}
			}
		}
	}

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

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