/*
 * 610_arch — archive selectivity. Build two .o files into an archive
 * where one defines a symbol main needs, and the other references an
 * undefined external. Linking should pull only the needed member;
 * the other one's bad reference must NOT cause a link error.
 *
 * If w6l were still pulling all members, this test would fail with
 * "undefined reference to 'this_symbol_does_not_exist'".
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/wait.h>

static int run(const char *cmd) { return system(cmd); }

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 dir[64];
	snprintf(dir, sizeof dir, "/tmp/wwarch_%d", getpid());
	mkdir(dir, 0755);

	/* lib_good.ww — defines f1() */
	char path[256];
	snprintf(path, sizeof path, "%s/lib_good.ww", dir);
	FILE *f = fopen(path, "wb");
	fputs("export fn f1() i32 = { return 7; };", f);
	fclose(f);

	/* lib_bad.ww — defines f2() but also references an undefined extern */
	snprintf(path, sizeof path, "%s/lib_bad.ww", dir);
	f = fopen(path, "wb");
	fputs("@symbol(\"this_symbol_does_not_exist\") fn bogus() i32;\n"
	      "export fn f2() i32 = { return bogus(); };", f);
	fclose(f);

	/* main.ww — calls f1, NOT f2 */
	snprintf(path, sizeof path, "%s/m.ww", dir);
	f = fopen(path, "wb");
	fputs("@symbol(\"f1\") fn f1() i32;\n"
	      "fn main() i32 = { return f1(); };", f);
	fclose(f);

	char cmd[2048];
	snprintf(cmd, sizeof cmd,
	    "set -e; cd %s && %s/w6c -o lib_good.s lib_good.ww && "
	    "%s/w6c -o lib_bad.s lib_bad.ww && "
	    "%s/w6a -o lib_good.o lib_good.s && %s/w6a -o lib_bad.o lib_bad.s && "
	    "ar rcs libfoo.a lib_good.o lib_bad.o && "
	    "%s/w6c -o m.s m.ww && %s/w6a -o m.o m.s",
	    dir, bin, bin, bin, bin, bin, bin);
	if (run(cmd) != 0) { fprintf(stderr, "build failed\n"); return 1; }

	/* Find start.o for the runtime */
	char startobj[256];
	snprintf(startobj, sizeof startobj, "%s/../obj/rt/start.o", bin);

	snprintf(cmd, sizeof cmd,
	    "%s/w6l -o %s/m %s/m.o %s %s/libfoo.a 2>%s/link.err",
	    bin, dir, dir, startobj, dir, dir);
	if (run(cmd) != 0) {
		FILE *ef = fopen("/dev/null", "r");
		(void)ef;
		char errpath[300];
		snprintf(errpath, sizeof errpath, "%s/link.err", dir);
		FILE *e = fopen(errpath, "r");
		if (e) {
			char buf[512]; size_t r = fread(buf, 1, sizeof buf - 1, e); buf[r]='\0'; fclose(e);
			fprintf(stderr, "link failed:\n%s\n", buf);
		}
		return 1;
	}

	char exepath[256];
	snprintf(exepath, sizeof exepath, "%s/m", dir);
	int rc = run(exepath);
	if (WIFEXITED(rc) && WEXITSTATUS(rc) == 7) {
		printf("arch: ok (only needed archive member pulled)\n");
		return 0;
	}
	fprintf(stderr, "arch: unexpected exit\n");
	return 1;
}