#include "Str.h"
#include "mars.h"
#include "op.h"
#include "xmalloc.h"

enum {MAGIC = 128};

static void null(struct mars **p, size_t n) {
	for (; n; --n) {
		p[n - 1] = NULL;
	}
}

void ma_init(struct mars *m) {
	m->data = NULL;
	m->table = xmalloc(m->size = MAGIC, sizeof *m->table);
	null(m->table, m->size);
}

void ma_end(struct mars *m) {
	for (; m->size; --m->size) {
		if (m->table[m->size - 1]) {
			ma_end(m->table[m->size - 1]);
			xfree(m->table[m->size - 1]);
		}
	}
	xfree(m->table);
}

int ma_enter(struct mars *m, const String *key, struct op *value) {
	size_t p;

	for (p = 0; p < St_len(key); ++p) {
		size_t tmp = ST_INDEX(key, p);
		if (m->size <= tmp) {
			m->table = xrealloc(m->table, m->size * 2);
			null(m->table + m->size, m->size);
			m->size *= 2;
		}
		if (!m->table[tmp]) {
			m->table[tmp] = xmalloc(1, sizeof *m->table[tmp]);
			ma_init(m->table[tmp]);
		}
		m = m->table[tmp];
	}

	if (m->data) {
		return -1;
	}
	m->data = value;
	return 0;
}

int ma_exists(const struct mars *m, const String *key) {
	size_t p;
	const struct op *ret = NULL;

	for (p = 0; p < St_len(key); ++p) {
		size_t tmp = ST_INDEX(key, p);
		ret = m->data;
		if (tmp >= m->size || !m->table[tmp]) {
			return 0;
		}
		m = m->table[tmp];
	}
	return ret != NULL;
}

struct op *ma_find(const struct mars *m, String *key) {
	size_t p;
	struct op *ret = NULL;

	for (p = 0; p < St_len(key); ++p) {
		size_t tmp = ST_INDEX(key, p);
		ret = m->data;
		if (tmp >= m->size || !m->table[tmp]) {
			break;
		}
		m = m->table[tmp];
	}
	if (ret) {
		St_del(key, 0, p);
	}
	return ret;
}