--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libmlk-adventure/adventure/action/chest.c	Sat Dec 12 12:16:47 2020 +0100
@@ -0,0 +1,153 @@
+/*
+ * chest.c -- chest object
+ *
+ * Copyright (c) 2020 David Demelier <markand@malikania.fr>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <core/animation.h>
+#include <core/event.h>
+#include <core/maths.h>
+#include <core/panic.h>
+#include <core/save.h>
+#include <core/sound.h>
+#include <core/sprite.h>
+
+#include <rpg/map.h>
+
+#include "chest.h"
+
+#define X(c)            ((c)->x - ((c)->map)->view_x)
+#define Y(c)            ((c)->y - ((c)->map)->view_y)
+#define W(c)            ((c)->animation.sprite->cellw)
+#define H(c)            ((c)->animation.sprite->cellh)
+#define TOLERANCE       (10)
+
+static bool
+is_near(const struct chest *c)
+{
+	const int x          = c->x - c->map->player_sprite->cellw - TOLERANCE;
+	const int y          = c->y - c->map->player_sprite->cellh - TOLERANCE;
+	const unsigned int w = W(c) + c->map->player_sprite->cellw + (TOLERANCE * 2);
+	const unsigned int h = H(c) + c->map->player_sprite->cellh + (TOLERANCE * 2);
+
+	return maths_is_boxed(x, y, w, h, c->map->player_x, c->map->player_y);
+}
+
+static void
+invoke(struct chest *c)
+{
+	c->state = CHEST_STATE_ANIMATE;
+
+	animation_start(&c->animation);
+
+	if (c->sound)
+		sound_play(c->sound, -1, 0);
+}
+
+static void
+handle(struct action *act, const union event *ev)
+{
+	struct chest *c = act->data;
+
+	if (!is_near(c) || c->state != CHEST_STATE_CLOSED)
+		return;
+
+	switch (ev->type) {
+	case EVENT_KEYDOWN:
+		if (ev->key.key == KEY_ENTER)
+			invoke(c);
+		break;
+	case EVENT_CLICKDOWN:
+		if (maths_is_boxed(X(c), Y(c), W(c), H(c), ev->click.x, ev->click.y))
+			invoke(c);
+		break;
+	default:
+		break;
+	}
+}
+
+static bool
+update(struct action *act, unsigned int ticks)
+{
+	struct chest *c = act->data;
+
+	if (c->state != CHEST_STATE_ANIMATE)
+		return false;
+
+	if (animation_update(&c->animation, ticks)) {
+		c->state = CHEST_STATE_OPEN;
+
+		if (c->exec)
+			c->exec(c);
+	}
+
+	return false;
+}
+
+static void
+draw(struct action *act)
+{
+	struct chest *c = act->data;
+
+	switch (c->state) {
+	case CHEST_STATE_OPEN:
+		sprite_draw(
+		    c->animation.sprite,
+		    c->animation.sprite->nrows - 1,
+		    c->animation.sprite->ncols - 1,
+		    X(c),
+		    Y(c)
+		);
+		break;
+	case CHEST_STATE_ANIMATE:
+		animation_draw(&c->animation, X(c), Y(c));
+		break;
+	default:
+		sprite_draw(c->animation.sprite, 0, 0, X(c), Y(c));
+		break;
+	}
+}
+
+void
+chest_init(struct chest *c)
+{
+	assert(c);
+
+	if (c->save && c->property) {
+		if (!save_get_property(c->save, c->property))
+			panic();
+
+		/* TODO: add an utility. */
+		if (strcmp(c->property->value, "true") == 0)
+			c->state = CHEST_STATE_OPEN;
+	}
+}
+
+struct action *
+chest_action(struct chest *c)
+{
+	assert(c);
+
+	c->action.data = c;
+	c->action.handle = handle;
+	c->action.update = update;
+	c->action.draw = draw;
+
+	return &c->action;
+}