// Copyright (c) 2023, Marvin Borner <dev@marvinborner.de>

#ifndef TEST
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <time.h>
#include <stdlib.h>

#include <reducer.h>
#include <gc.h>
#include <parse.h>

static void callback(int i, char ch, void *data)
{
	(void)i;
	(void)ch;
	(void)data;
	/* printf("%d: %c\n", i, ch); */
}

#define BUF_SIZE 1024
static char *read_stdin(void)
{
	char buffer[BUF_SIZE];
	size_t size = 1;
	char *string = malloc(sizeof(char) * BUF_SIZE);
	if (!string)
		return 0;
	string[0] = '\0';
	while (fgets(buffer, BUF_SIZE, stdin)) {
		char *old = string;
		size += strlen(buffer);
		string = realloc(string, size);
		if (!string) {
			free(old);
			return 0;
		}
		strcat(string, buffer);
	}

	if (ferror(stdin)) {
		free(string);
		fprintf(stderr, "Couldn't read from stdin\n");
		return 0;
	}
	return string;
}

static char *read_file(const char *path)
{
	FILE *f = fopen(path, "rb");
	if (!f) {
		fprintf(stderr, "Can't open file %s: %s\n", path,
			strerror(errno));
		return 0;
	}

	fseek(f, 0, SEEK_END);
	long fsize = ftell(f);
	fseek(f, 0, SEEK_SET);

	char *string = malloc(fsize + 1);
	int ret = fread(string, fsize, 1, f);
	fclose(f);

	if (ret != 1) {
		fprintf(stderr, "Can't read file %s: %s\n", path,
			strerror(errno));
		return 0;
	}

	string[fsize] = 0;
	return string;
}

int main(int argc, char **argv)
{
	GC_INIT();
	GC_enable_incremental();

	if (argc < 2) {
		fprintf(stderr, "Invalid arguments\n");
		return 1;
	}

	char *input;
	if (argv[1][0] == '-') {
		input = read_stdin();
	} else {
		input = read_file(argv[1]);
	}

	if (!input)
		return 1;

	struct term *parsed = parse_blc(input);

	clock_t begin = clock();
	struct term *reduced = reduce(parsed, callback, 0);
	clock_t end = clock();
	fprintf(stderr, "reduced in %.5fs\n",
		(double)(end - begin) / CLOCKS_PER_SEC);

	to_bruijn(reduced);
	print_blc(reduced);
	free_term(reduced);
	free_term(parsed);
	free(input);
	return 0;
}
#else
__attribute__((unused)) static int testing;
#endif