/*
 * w6c — amd64 compiler driver. Reads a .ww source file, runs the
 * libwcc frontend (lex → parse → check), then walks the typed AST
 * via cgen.c and writes Plan 9-flavoured amd64 asm to stdout (or
 * the file given by -o).
 */
#include "gc.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

static int
slurp(const char *path, char **outbuf, u64 *outlen)
{
	FILE *f = fopen(path, "rb");
	if (f == NULL) return -1;
	fseek(f, 0, SEEK_END);
	long n = ftell(f);
	fseek(f, 0, SEEK_SET);
	if (n < 0) { fclose(f); return -1; }
	char *b = malloc((size_t)n + 1);
	if (b == NULL) { fclose(f); return -1; }
	if (fread(b, 1, (size_t)n, f) != (size_t)n) { free(b); fclose(f); return -1; }
	b[n] = '\0';
	fclose(f);
	*outbuf = b;
	*outlen = (u64)n;
	return 0;
}

int
main(int argc, char **argv)
{
	const char *src = NULL;
	const char *out = NULL;
	for (int i = 1; i < argc; i++) {
		const char *a = argv[i];
		if (strcmp(a, "-o") == 0 && i + 1 < argc) {
			out = argv[++i];
		} else if (a[0] == '-') {
			fprintf(stderr, "w6c: unknown flag %s\n", a);
			return 2;
		} else if (src == NULL) {
			src = a;
		} else {
			fprintf(stderr, "w6c: only one input supported\n");
			return 2;
		}
	}
	if (src == NULL) {
		fputs("usage: w6c [-o out.s] file.ww\n", stderr);
		return 2;
	}

	char *buf;
	u64 len;
	if (slurp(src, &buf, &len) < 0) {
		fprintf(stderr, "w6c: %s: cannot read\n", src);
		return 1;
	}

	Arena *a = newarena();
	Lex l;
	Parser p;
	Checker c;
	Cg cg;

	lexinit(&l, a, src, buf, len);
	parserinit(&p, a, &l);
	Node *file = parsefile(&p);
	if (l.errs || p.errs) return 1;

	check_init(&c, a);
	check_file(&c, file);
	if (c.errs) return 1;

	FILE *of = stdout;
	if (out) {
		of = fopen(out, "wb");
		if (of == NULL) {
			fprintf(stderr, "w6c: cannot open %s\n", out);
			return 1;
		}
	}

	cg_init(&cg, a);
	cg_file(&cg, of, file);

	if (of != stdout) fclose(of);
	freearena(a);
	free(buf);
	return 0;
}