veloren/common/src/states/basic_melee.rs

use crate::{
    comp::{Attacking, CharacterState, EnergySource, StateUpdate},
    states::utils::*,
    sys::character_behavior::{CharacterBehavior, JoinData},
};
use serde::{Deserialize, Serialize};
use std::time::Duration;

#[derive(Copy, Clone, Debug, PartialEq, Serialize, Deserialize)]
pub struct Data {
    /// How long until state should deal damage
    pub buildup_duration: Duration,
    /// How long the state has until exiting
    pub recover_duration: Duration,
    /// Base damage (negative) or healing (positive)
    pub base_healthchange: i32,
    /// Knockback
    pub knockback: f32,
    /// Max range
    pub range: f32,
    /// Max angle (45.0 will give you a 90.0 angle window)
    pub max_angle: f32,
    /// Whether the attack can deal more damage
    pub exhausted: bool,
}

impl CharacterBehavior for Data {
    fn behavior(&self, data: &JoinData) -> StateUpdate {
        let mut update = StateUpdate::from(data);

        handle_move(data, &mut update, 0.7);
        handle_jump(data, &mut update);

        if self.buildup_duration != Duration::default() {
            // Build up
            update.character = CharacterState::BasicMelee(Data {
                buildup_duration: self
                    .buildup_duration
                    .checked_sub(Duration::from_secs_f32(data.dt.0))
                    .unwrap_or_default(),
                recover_duration: self.recover_duration,
                base_healthchange: self.base_healthchange,
                knockback: self.knockback,
                range: self.range,
                max_angle: self.max_angle,
                exhausted: false,
            });
        } else if !self.exhausted {
            let (damage, heal) = if self.base_healthchange > 0 {
                (0, self.base_healthchange as u32)
            } else {
                ((-self.base_healthchange) as u32, 0)
            };
            // Hit attempt
            data.updater.insert(data.entity, Attacking {
                base_damage: damage,
                base_heal: heal,
                range: self.range,
                max_angle: self.max_angle.to_radians(),
                applied: false,
                hit_count: 0,
                knockback: self.knockback,
            });

            update.character = CharacterState::BasicMelee(Data {
                buildup_duration: self.buildup_duration,
                recover_duration: self.recover_duration,
                base_healthchange: self.base_healthchange,
                knockback: self.knockback,
                range: self.range,
                max_angle: self.max_angle,
                exhausted: true,
            });
        } else if self.recover_duration != Duration::default() {
            // Recovery
            update.character = CharacterState::BasicMelee(Data {
                buildup_duration: self.buildup_duration,
                recover_duration: self
                    .recover_duration
                    .checked_sub(Duration::from_secs_f32(data.dt.0))
                    .unwrap_or_default(),
                base_healthchange: self.base_healthchange,
                knockback: self.knockback,
                range: self.range,
                max_angle: self.max_angle,
                exhausted: true,
            });
        } else {
            // Done
            update.character = CharacterState::Wielding;
            // Make sure attack component is removed
            data.updater.remove::<Attacking>(data.entity);
        }

        // Grant energy on successful hit
        if let Some(attack) = data.attacking {
            if attack.applied && attack.hit_count > 0 {
                data.updater.remove::<Attacking>(data.entity);
                update.energy.change_by(50, EnergySource::HitEnemy);
            }
        }

        update
    }
}