/*
 * 989_m1mangle_sym — M1 (#22) symbol-name proof. Builds a fixture that
 * imports the real nested DIRECTORY package `encoding.utf8` to `.s` on
 * BOTH stages and asserts the emitted symbol table:
 *
 *   needle                    | want | proves
 *   --------------------------+------+-----------------------------------
 *   "encoding.utf8.runesz"    | yes  | nested pkg path-mangles (the M1
 *                             |      |   DELTA: leaf `utf8` → path
 *                             |      |   `encoding.utf8`)
 *   "TEXT main,"              | yes  | root entry stays BARE (#32)
 *   "TEXT utf8.runesz,"       | no   | the pre-M1 leaf-only mangle is gone
 *
 * Plus cstage.s == wwstage.s byte-for-byte on the re-baselined names
 * (rule-10 — the cs==ww gate over the new symbols).
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.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;
}

static int
file_has(const char *path, const char *needle)
{
	FILE *f = fopen(path, "rb");
	if (!f) return -1;
	char line[4096];
	int found = 0;
	while (fgets(line, sizeof line, f)) {
		if (strstr(line, needle)) { found = 1; break; }
	}
	fclose(f);
	return found;
}

struct check { const char *needle; int want; };

static const struct check checks[] = {
	{ "encoding.utf8.runesz", 1 },
	{ "TEXT main,",           1 },
	{ "TEXT utf8.runesz,",    0 },
};

/* build_s — build `src` to `<stem>.s` via `driver`; returns 0 on success. */
static int
build_s(const char *driver, const char *src, const char *stem)
{
	char cmd[1024];
	snprintf(cmd, sizeof cmd, "%s build -o '%s' '%s' 2>/dev/null",
	    driver, stem, src);
	return runwait(cmd);
}

static int
checkall(const char *name, const char *sp)
{
	int fail = 0;
	for (int i = 0; i < (int)(sizeof checks / sizeof checks[0]); i++) {
		int got = file_has(sp, checks[i].needle);
		if (got != checks[i].want) {
			fprintf(stderr, "m1mangle_sym[%s]: '%s' present=%d want=%d\n",
			    name, checks[i].needle, got, checks[i].want);
			fail++;
		}
	}
	return fail;
}

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 cdrv[1024], wdrv[1024];
	snprintf(cdrv, sizeof cdrv, "%s/ww", bin);
	snprintf(wdrv, sizeof wdrv, "%s/ww_ww", bin);

	char src[64];
	snprintf(src, sizeof src, "/tmp/m1sym_%d.ww", getpid());
	FILE *f = fopen(src, "wb");
	if (!f) return 1;
	fputs("package main;\n"
	      "import encoding.utf8;\n"
	      "export fn main() int = { return utf8.runesz('A'): int; };\n", f);
	fclose(f);

	int fail = 0;

	char cstem[64], cs[80];
	snprintf(cstem, sizeof cstem, "/tmp/m1sym_c_%d", getpid());
	snprintf(cs, sizeof cs, "%s.s", cstem);
	if (build_s(cdrv, src, cstem) != 0) {
		fprintf(stderr, "m1mangle_sym: cstage build failed\n");
		fail++;
	} else {
		fail += checkall("cstage", cs);
	}

	int have_ww = (access(wdrv, X_OK) == 0);
	char wstem[64], ws[80];
	snprintf(wstem, sizeof wstem, "/tmp/m1sym_w_%d", getpid());
	snprintf(ws, sizeof ws, "%s.s", wstem);
	if (have_ww) {
		if (build_s(wdrv, src, wstem) != 0) {
			fprintf(stderr, "m1mangle_sym: wwstage build failed\n");
			fail++;
		} else {
			fail += checkall("wwstage", ws);
			/* rule-10: cs.s == ww.s on the new mangled names. */
			char cmp[256];
			snprintf(cmp, sizeof cmp, "cmp -s '%s' '%s'", cs, ws);
			if (runwait(cmp) != 0) {
				fprintf(stderr, "m1mangle_sym: cstage.s != "
				    "wwstage.s (byte-id break)\n");
				fail++;
			}
		}
	} else {
		fprintf(stderr, "m1mangle_sym: skip wwstage (no ww_ww)\n");
	}

	char cmd[256];
	snprintf(cmd, sizeof cmd, "rm -f '%s' '%s'* '%s'*", src, cstem, wstem);
	runwait(cmd);

	if (fail) {
		fprintf(stderr, "m1mangle_sym: %d checks failed\n", fail);
		return 1;
	}
	printf("m1mangle_sym: ok\n");
	return 0;
}