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

#include <tfe_future.h>
#include <tfe_utils.h>

struct future
{
	void * user;
	future_success_cb * cb_success;
	future_failed_cb * cb_failed;
};

struct promise
{
	struct future f;
	void * ctx;
	promise_ctx_destroy_cb * cb_ctx_destroy;
};

struct future * promise_to_future(struct promise * p)
{
	return &p->f;
}

struct promise * future_to_promise(struct future * f)
{
	return (struct promise *) f;
}

struct future * future_create(future_success_cb * cb_success, future_failed_cb * cb_failed, void * user)
{
	struct promise * p = ALLOC(struct promise, 1);
	p->f.user = user;
	p->f.cb_success = cb_success;
	p->f.cb_failed = cb_failed;
	return &p->f;
}

void future_destroy(struct future * f)
{
	struct promise * promise = future_to_promise(f);
	if (promise->cb_ctx_destroy != NULL)
	{
		promise->cb_ctx_destroy(promise);
	}

	memset(promise, 0, sizeof(struct promise));
	free(promise);
}

void promise_failed(struct promise * p, enum e_future_error error, const char * what)
{
	p->f.cb_failed(error, what, p->f.user);
	return;
}

void promise_success(struct promise * p, void * result)
{
	p->f.cb_success(result, p->f.user);
	return;
}

void promise_set_ctx(struct promise * p, void * ctx, promise_ctx_destroy_cb * cb)
{
	p->ctx = ctx;
	p->cb_ctx_destroy = cb;
	return;
}

void * promise_get_ctx(struct promise * p)
{
	return p->ctx;
}

void * promise_dettach_ctx(struct promise * p)
{
	void * ctx = p->ctx;
	p->ctx = NULL;
	p->cb_ctx_destroy = NULL;
	return ctx;
}