/*
 * 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;

import fr.quatrevieux.araknemu.data.living.entity.player.PlayerItem;
import fr.quatrevieux.araknemu.game.item.Item;
import fr.quatrevieux.araknemu.game.item.effect.ItemEffect;
import fr.quatrevieux.araknemu.game.item.inventory.AbstractItemEntry;
import fr.quatrevieux.araknemu.game.item.inventory.event.ObjectMoved;
import fr.quatrevieux.araknemu.game.item.inventory.exception.InventoryException;
import fr.quatrevieux.araknemu.game.player.inventory.slot.InventorySlots;
import fr.quatrevieux.araknemu.util.Asserter;
import org.checkerframework.checker.index.qual.Positive;
import org.checkerframework.common.value.qual.IntRange;
import org.checkerframework.dataflow.qual.Pure;

import java.util.stream.Collectors;

/**
 * Entry for player repository
 */
public final class InventoryEntry extends AbstractItemEntry {
    private final PlayerInventory inventory;
    private final PlayerItem entity;
    private final Item item;

    public InventoryEntry(PlayerInventory inventory, PlayerItem entity, Item item) {
        super(inventory, entity, item, inventory);

        this.inventory = inventory;
        this.entity = entity;
        this.item = item;
    }

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

    /**
     * Move the entry to a new position
     * If the item is already in the given position, nothing is done
     *
     * @param position The new position
     * @param quantity Quantity to move
     *
     * @throws InventoryException When cannot move the item
     * @throws fr.quatrevieux.araknemu.game.item.inventory.exception.BadLevelException When the player level is too low for the item
     * @throws fr.quatrevieux.araknemu.game.item.inventory.exception.AlreadyEquippedException When the item is already equipped
     */
    public void move(@IntRange(from = -1, to = InventorySlots.SLOT_MAX) int position, @Positive int quantity) throws InventoryException {
        if (quantity > quantity() || quantity <= 0) {
            throw new InventoryException("Invalid quantity given");
        }

        if (position == position()) {
            return;
        }

        if (quantity == quantity()) {
            if (inventory.move(this, position)) {
                changePosition(position);
            }

            return;
        }

        inventory.add(item, quantity, position);
        remove(quantity);
    }

    /**
     * Move all the entry to the default position
     * This can be used to unequip the item
     *
     * This is equivalent of calling `move(DEFAULT_POSITION, quantity())`
     *
     * This method will do nothing if the item is already on the default position
     */
    public void unequip() {
        move(DEFAULT_POSITION, Asserter.assertPositive(quantity()));
    }

    /**
     * Set the item to the default position
     * Note: this method is internal and should not be called
     *
     * @see #unequip() To unequip the item (this method should be called instead)
     */
    public void setToDefaultPosition() {
        entity.setPosition(DEFAULT_POSITION);
    }

    /**
     * Get the database entity
     */
    @Pure
    PlayerItem entity() {
        return entity;
    }

    private void changePosition(@IntRange(from = -1, to = InventorySlots.SLOT_MAX) int position) {
        entity.setPosition(position);
        inventory.dispatch(new ObjectMoved(this));
    }

    /**
     * Create a new entry
     */
    static InventoryEntry create(PlayerInventory inventory, int id, Item item, @Positive int quantity, @IntRange(from = -1, to = InventorySlots.SLOT_MAX) int position) {
        return new InventoryEntry(
            inventory,
            new PlayerItem(
                inventory.owner().id(),
                id,
                item.template().id(),
                item.effects().stream().map(ItemEffect::toTemplate).collect(Collectors.toList()),
                quantity,
                position
            ),
            item
        );
    }
}