/*
 * This file is part of Araknemu.
 *
 * Araknemu is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Araknemu is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Araknemu.  If not, see <https://www.gnu.org/licenses/>.
 *
 * Copyright (c) 2017-2019 Vincent Quatrevieux
 */

package fr.quatrevieux.araknemu.game.player.inventory.slot;

import fr.quatrevieux.araknemu.game.item.Item;
import fr.quatrevieux.araknemu.game.item.inventory.ItemStorage;
import fr.quatrevieux.araknemu.game.item.inventory.exception.InventoryException;
import fr.quatrevieux.araknemu.game.player.inventory.InventoryEntry;
import fr.quatrevieux.araknemu.game.player.inventory.slot.constraint.SlotConstraint;
import org.checkerframework.checker.index.qual.Positive;
import org.checkerframework.checker.nullness.qual.Nullable;
import org.checkerframework.common.value.qual.IntRange;

import java.util.Optional;

/**
 * Base slot class
 */
public final class SimpleSlot implements InventorySlot {
    private final @IntRange(from = -1, to = InventorySlots.SLOT_MAX) int id;
    private final SlotConstraint[] constraints;
    private final ItemStorage<InventoryEntry> storage;

    private @Nullable InventoryEntry entry;

    public SimpleSlot(@IntRange(from = -1, to = InventorySlots.SLOT_MAX) int id, SlotConstraint[] constraints, ItemStorage<InventoryEntry> storage) {
        this.id = id;
        this.constraints = constraints;
        this.storage = storage;
    }

    @Override
    public @IntRange(from = -1, to = InventorySlots.SLOT_MAX) int id() {
        return id;
    }

    @Override
    public Optional<InventoryEntry> entry() {
        return Optional.ofNullable(entry);
    }

    @Override
    public void check(Item item, int quantity) throws InventoryException {
        if (entry != null) {
            throw new InventoryException("Slot is full");
        }

        for (SlotConstraint constraint : constraints) {
            constraint.check(item, quantity);
        }
    }

    @Override
    public InventoryEntry set(InventoryEntry entry) throws InventoryException {
        check(entry.item(), entry.quantity());

        uncheckedSet(entry);

        return entry;
    }

    @Override
    public InventoryEntry set(Item item, @Positive int quantity) throws InventoryException {
        check(item, quantity);

        return entry = storage.add(item, quantity, id);
    }

    @Override
    public void uncheckedSet(@Nullable InventoryEntry entry) {
        this.entry = entry;
    }
}