/*
 * 110_uniesc_run — .wwi round-trip carrier for \u / \U Unicode escapes.
 *
 * The value-row half (rune/string \u \U \x decode asserts) migrated to the
 * in-language row-table test/lang/uniesc_test.ww (fold-6, task #4); this
 * file retains ONLY the .wwi round-trip case, which is a two-package
 * sep-build observer with no in-language @test home (it asserts the
 * PRODUCER re-serializes a wide-rune `def` byte-exact, observed across a
 * package boundary — not expressible as a single-compile @test).
 *
 * An exported wide-rune `def` re-serialized by the producer must re-parse
 * into the same codepoint (the write-twin of the lexer read-fix —
 * cmd/w6c/wwi.c wwi_rune / selfhost/cmd/wcc/wwi.ww wwirune emit \u/\U above
 * 0xFF). Runs through both the cstage `ww` and wwstage `ww_ww` drivers
 * (task #50); the wwstage arm is skipped when ww_ww is absent (a
 * cstage-only build), mirroring 640_int_cast_signed.
 */
#include <stdio.h>
#include <stdlib.h>
#include <errno.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;
}

/* run_roundtrip — sep-build a two-package program where the imported
 * package exports wide-rune defs; the producer must serialize them as
 * \u/\U so the importer re-parses the same codepoint. Returns the built
 * program's exit code (42 on a correct round-trip). */
static int
run_roundtrip(const char *driver, int id)
{
	char dir[80], wrdir[112], wrp[176], mainp[160], cmd[1024];
	char outbin[160], scratch[176];
	snprintf(dir, sizeof dir, "/tmp/wwue_rt_%d_%d", getpid(), id);
	snprintf(wrdir, sizeof wrdir, "%s/wr", dir);
	snprintf(wrp, sizeof wrp, "%s/wr.ww", wrdir);
	snprintf(mainp, sizeof mainp, "%s/main.ww", dir);
	snprintf(outbin, sizeof outbin, "%s/main", dir);
	snprintf(scratch, sizeof scratch, "%s/main.sepwork", dir);

	if (mkdir(dir, 0755) != 0) {
		perror(dir);
		return -1;
	}
	int got = -1;
	int wr_owned = 0;
	if (mkdir(wrdir, 0755) != 0) {
		perror(wrdir);
		goto cleanup;
	}
	wr_owned = 1;

	FILE *f = fopen(wrp, "wb");
	if (!f) {
		perror(wrp);
		goto cleanup;
	}
	/* one def per serializer branch: \x (<=0xFF), \u (<=0xFFFF), \U. */
	fputs("package wr;\n"
	      "export def EACUTE: rune = '\\u00e9';\n"
	      "export def EURO: rune = '\\u20ac';\n"
	      "export def SMILEY: rune = '\\U0001F600';\n", f);
	if (fclose(f) != 0) {
		perror(wrp);
		goto cleanup;
	}
	f = fopen(mainp, "wb");
	if (!f) {
		perror(mainp);
		goto cleanup;
	}
	fputs("package main;\n"
	      "import wr;\n"
	      "fn main() i32 = {\n"
	      "  let a: rune = wr.EACUTE;\n"
	      "  let b: rune = wr.EURO;\n"
	      "  let c: rune = wr.SMILEY;\n"
	      "  if ((a: u32) != 233u32) { return 1; };\n"
	      "  if ((b: u32) != 8364u32) { return 2; };\n"
	      "  if ((c: u32) != 128512u32) { return 3; };\n"
	      "  return 42;\n"
	      "};\n", f);
	if (fclose(f) != 0) {
		perror(mainp);
		goto cleanup;
	}

	snprintf(cmd, sizeof cmd, "cd %s && %s build main.ww", dir, driver);
	if (runwait(cmd) != 0) {
		fprintf(stderr, "roundtrip: build via %s failed\n", driver);
		goto cleanup;
	}
	got = runwait(outbin);

cleanup:
	/* `ww build` retains this exact caller-owned scratch tree. */
	snprintf(cmd, sizeof cmd, "rm -rf %s", scratch);
	int cleanfail = runwait(cmd) != 0;
	if (unlink(outbin) != 0 && errno != ENOENT) {
		perror(outbin);
		cleanfail = 1;
	}
	if (unlink(mainp) != 0 && errno != ENOENT) {
		perror(mainp);
		cleanfail = 1;
	}
	if (wr_owned) {
		if (unlink(wrp) != 0 && errno != ENOENT) {
			perror(wrp);
			cleanfail = 1;
		}
		if (rmdir(wrdir) != 0) {
			perror(wrdir);
			cleanfail = 1;
		}
	}
	if (rmdir(dir) != 0) {
		perror(dir);
		cleanfail = 1;
	}
	if (cleanfail && got == 42)
		got = -1;
	return got;
}

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

	struct { const char *name; const char *path; int gated_on_existence; }
	drivers[] = {
		{ "cstage", cdrv, 0 },
		{ "wwstage", wdrv, 1 },
		{ NULL, NULL, 0 },
	};

	int total = 0, fail = 0;
	for (int d = 0; drivers[d].name; d++) {
		if (drivers[d].gated_on_existence
		    && access(drivers[d].path, X_OK) != 0) {
			fprintf(stderr, "uniesc_run: skip %s (no %s)\n",
			    drivers[d].name, drivers[d].path);
			continue;
		}
		int rt = run_roundtrip(drivers[d].path, d);
		total++;
		if (rt != 42) {
			fprintf(stderr,
			    "uniesc_run[%s][wwi_roundtrip]: exit=%d want=42\n",
			    drivers[d].name, rt);
			fail++;
		}
	}
	if (fail) {
		fprintf(stderr, "uniesc_run: %d/%d fixtures failed\n",
		    fail, total);
		return 1;
	}
	printf("uniesc_run: %d/%d ok\n", total, total);
	return 0;
}