/* SPDX-License-Identifier: GPL-3.0-or-later */
/* Copyright (C) 2021 KikooDX */

#include "input.h"
#include "levelselection.h"
#include "pack_count.h"
#include "util.h"

/* Return 1 if game state should change.
 * Return -1 to return to main menu. */
int
levelselection_update(struct LevelSelection *restrict levelselection,
                      struct Input input)
{
	/* decrease selected pack id */
	if (input.keystates[K_LEFT] == KS_PRESS &&
	    levelselection->pack_cursor > 0) {
		levelselection->pack_cursor -= 1;
		levelselection->visual_target =
		    (float)levelselection->pack_cursor;
	}
	/* increase selected pack id */
	if (input.keystates[K_RIGHT] == KS_PRESS &&
	    levelselection->pack_cursor < PACK_COUNT - 1) {
		levelselection->pack_cursor += 1;
		levelselection->visual_target =
		    (float)levelselection->pack_cursor;
	}

	if (input.keystates[K_START] == KS_PRESS) {
		levelselection->visual_cursor =
		    (float)levelselection->pack_cursor;
		levelselection->visual_target = levelselection->visual_cursor;
		return -1;
	} else if (input.keystates[K_A] == KS_PRESS) {
		levelselection->visual_cursor =
		    (float)levelselection->pack_cursor;
		levelselection->visual_target = levelselection->visual_cursor;
		return 1;
	}

	/* lerp visual cursor to visual target */
	levelselection->visual_cursor +=
	    PACKBOX_TRANSITION_SPEED *
	    (levelselection->visual_target - levelselection->visual_cursor);

	return 0;
}