package carpetclient.mixins;

import carpetclient.Config;
import net.minecraft.entity.Entity;

import org.spongepowered.asm.lib.Opcodes;
import org.spongepowered.asm.mixin.Mixin;
import org.spongepowered.asm.mixin.Shadow;
import org.spongepowered.asm.mixin.injection.At;
import org.spongepowered.asm.mixin.injection.Inject;
import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;

/*
A Mixins class to override a method to change the players aim.
 */
@Mixin(Entity.class)
public abstract class MixinsEntity {

    @Shadow
    public float rotationYaw;
    @Shadow
    public float rotationPitch;
    @Shadow
    public float prevRotationPitch;
    @Shadow
    public float prevRotationYaw;
    @Shadow
    private Entity ridingEntity;

    private float storedRotationYaw;

    /*
    Injection to modify the behavior of player aiming.
     */
    @Inject(method = "turn", at = @At(value = "FIELD", target = "Lnet/minecraft/entity/Entity;prevRotationPitch:F", opcode = Opcodes.PUTFIELD))
    public void post(float yaw, float pitch, CallbackInfo ci) {
        snapAim(this.ridingEntity != null, yaw);
    }

    /**
     * Overriding the aim of the player to snap to angles of 45 degrees
     * @param inBoat Checks if the player is riding a boat to skip snapping.
     * @param yaw The angle in which the player will turn, sent in from the turn method.
     */
    private void snapAim(boolean inBoat, float yaw) {
        if (inBoat || !Config.snapAim) return;

        this.storedRotationYaw = (float) ((double) this.storedRotationYaw + (double) yaw * 0.15D);

        float r = storedRotationYaw - storedRotationYaw % 45;
        float r2 = Math.abs(r - storedRotationYaw);
        if (r2 < 5) {
            this.rotationYaw = r;
        } else if (r2 > 40) {
            if (storedRotationYaw < 0)
                this.rotationYaw = r - 45;
            else
                this.rotationYaw = r + 45;
        } else {
            this.rotationYaw = storedRotationYaw;
        }
    }
}