#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>

#include "oper.h"
#include "panic.h"
#include "byte_slice.h"

static uint8_t_slice xrealloc(void *ptr, size_t size)
{
	void *p = realloc(ptr, size);
	if (!p) {
		panicf("Out of memory!\n");
	}
	return (uint8_t_slice) {
		.buf = p,
		.size = size,
	};
}

static uint8_t_slice read_file(char *filename)
{
	FILE *f = fopen(filename, "r");
	if (!f) {
		panicf("File %s does not exit!\n", filename);
	}
	uint8_t_slice out = { .size = 0, .buf = NULL };
	size_t offset = 0;
	while (true) {
		if (offset >= out.size) {
			size_t new_size = 2 * out.size + 1;
			out = xrealloc(out.buf, new_size);
		}
		size_t read_size = out.size - offset;
		size_t n = fread(out.buf + offset, 1, read_size, f);
		if (n < read_size) {
			if (ferror(f)) {
				panicf("Read error!\n");
			}
			return uint8_t_slice2(out, 0, offset + n);
		}
		offset += n;
	}
}

int main(int argc, char **argv)
{
	if (argc < 2) {
		printf("Usage error: need a filename.\n");
		return 1;
	}

	uint8_t_slice program = read_file(argv[1]);

	run(program);

	// run never returns. I'm just putting this here to taunt you:
	free(program.buf);
}