package org.arios.game.container.access;

import org.arios.game.node.entity.player.Player;

/**
 * Contains the mask value methods. The 'access mask' is actually just a bit
 * register that contains permissions for a specific interface (@Peterbjornx)
 * @date 5/02/2013
 * @author Stacx
 * @author Emperor
 */
public final class BitregisterAssembler {

    /**
     * The register size.
     */
    public static final int SIZE = 32 - 1;

    /**
     * Examine option.
     */
    public static final int EXAMINE_OPT = 9;

    /**
     * Allow dragging.
     */
    public static final int DRAGABLE = 17;

    /**
     * Allow switching item slots.
     */
    public static final int SLOT_SWITCH = 20;

    /**
     * The flags.
     */
    private boolean[] permissions = new boolean[SIZE];

    /**
     * Constructs a new {@code BitregisterAssembler} {@code Object}.
     * @param permissions The permissions.
     */
    public BitregisterAssembler(int... permissions) {
        for (int i : permissions) {
            this.permissions[i] = true;
        }
    }

    /**
     * Constructs a new {@code BitregisterAssembler} {@code Object}.
     * @param permissions The permissions.
     */
    public BitregisterAssembler(String[] options) {
        enableOptions(options);
    }

    /**
     * Enables the given options ({@code null} options will remain disabled).
     * @param options The options.
     */
    public void enableOptions(String...options) {
        if (options.length > 9) {
            throw new IllegalStateException("Too many options specified - maximum 9 allowed!");
        }
        for (int i = 0; i < options.length; i++) {
            if (options[i] != null && !options[i].equals("null")) {
                permissions[i] = true;
            }
        }
    }

    /**
     * Enables the examine option.
     */
    public void enableExamineOption() {
        permissions[EXAMINE_OPT] = true;
    }

    /**
     * Enables items being dragged.
     */
    public void enableDragging() {
        permissions[DRAGABLE] = true;
    }

    /**
     * Enables item switching slots (& dragging).
     */
    public void enableSlotSwitch() {
        enableDragging();
        permissions[SLOT_SWITCH] = true;
    }

    /**
     * <b>Send</b> and assemble a bit register for our
     * @param player , the player instance
     * @param interfaceIndex , the interface index
     * @param childIndex , the child index for our interface
     * @param offset , the offset for the loop in client
     * @param length , the length of our loop
     */
    public static void send(Player player, int interfaceIndex, int childIndex, int offset, int length, BitregisterAssembler assembler) {
        if (offset >= length) {
            throw new RuntimeException("Offset cannot excess length. length = " + length);
        }
        player.getPacketDispatch().sendAccessMask(assembler.calculateRegister(), childIndex, interfaceIndex, offset, length);
    }

    /**
     * Calculates the register.
     * @return The value.
     */
    public int calculateRegister() {
        int value = 0;
        for (int i = 0; i < SIZE; i++) {
            if (permissions[i]) {
                value |= 2 << i;
            }
        }
        return value;
    }

}