shinespark/src/fighter/state/ground_attack.rs

use bevy::{asset::Assets, log::error};

use crate::{
    fighter::{
        attack::{AttackKind, FighterAttackScriptAssets, update_active_attack},
        state::{
            CollisionContext, EnterContext, ExitContext, FighterState, FighterStateImpl,
            InterruptContext, UpdateContext, ground, wait::WaitState,
        },
    },
    scripting::FighterAttackScript,
};

#[derive(Clone, Debug, Hash)]
pub struct GroundAttackState {
    pub attack_kind: AttackKind,
    pub use_root_motion: bool,
}

impl FighterStateImpl for GroundAttackState {
    const NAME: &'static str = "GroundAttack";

    fn check_interrupt(&self, state_context: &mut InterruptContext) -> Option<FighterState> {
        // Allow interrupting dash attack only into an up/down smash
        if let AttackKind::DashAttack = self.attack_kind {
            if state_context.get_current_animation_frame() < state_context.fighter_attributes.dash_attack_cancel_window {
                if let Some(state) = check_interrupt(state_context) {
                    if let FighterState::GroundAttack(state) = state {
                        if matches!(state.attack_kind, AttackKind::UpSmash) || matches!(state.attack_kind, AttackKind::DownSmash) {
                            return Some(FighterState::GroundAttack(state));
                        }
                    }
                }
            }
        }

        if state_context.is_current_animation_finished() {
            Some(FighterState::Wait(WaitState))
        } else {
            None
        }
    }

    fn update(&mut self, state_context: &mut UpdateContext) {
        let animation_frame = state_context.get_current_animation_frame();
        let script = state_context
            .attack_scripts
            .get(&state_context.attack_script_assets.scripts[&self.attack_kind]);
        if let Some(script) = script {
            update_active_attack(
                script,
                state_context
                    .hitboxes
                    .0
                    .as_mut()
                    .expect("ground attack must have active hitboxes"),
                animation_frame,
            );

            // root motion
            if script.use_root_motion {
                state_context.velocity.0.x = state_context.animation_root_motion_delta.x;
                ground::apply_grounded_motion(
                    state_context.velocity,
                    state_context.translation,
                );
            } else {
                ground::update_friction_motion(state_context);
            }
        }
    }

    fn on_enter(&mut self, state_context: &mut EnterContext) {
        state_context
            .input
            .consume_command(crate::input::FighterCommands::Attack);
        state_context.play_animation(self.attack_kind.get_animation(), false);
        let script = state_context.attack_script_assets.scripts[&self.attack_kind].clone();
        state_context.hitboxes.0 = Some(crate::fighter::FighterActiveAttack {
            kind: self.attack_kind,
            script: script.clone(),
            active_hitboxes: Vec::new(),
            solved_hitboxes: Vec::new(),
            hit_groups: Vec::new(),
            stalled: false,
        });
    }

    fn on_exit(&mut self, state_context: &mut ExitContext) {
        state_context.hitboxes.0 = None;
    }

    fn check_collision_interrupt(
        &mut self,
        state_context: &mut CollisionContext,
    ) -> Option<FighterState> {
        ground::collision_interrupt(state_context, !self.use_root_motion)
    }

    fn is_visually_grounded<'a>(&'a self) -> bool {
        true
    }
}

impl GroundAttackState {
    fn create(
        attack_kind: AttackKind,
        attack_script_assets: &FighterAttackScriptAssets,
        attack_scripts: &Assets<FighterAttackScript>,
    ) -> Result<Self, AirAttackStateCreateError> {
        let asset_script = attack_script_assets.scripts.get(&attack_kind).ok_or(
            AirAttackStateCreateError::AttackScriptAssetNotFound {
                attack: attack_kind,
            },
        )?;

        let script = attack_scripts.get(asset_script).ok_or(
            AirAttackStateCreateError::AttackScriptNotFound {
                attack: attack_kind,
            },
        )?;

        Ok(Self {
            attack_kind,
            use_root_motion: script.use_root_motion
        })
    }
}

#[derive(thiserror::Error, Debug)]
pub enum AirAttackStateCreateError {
    #[error("Attack script: {attack:?} not found")]
    AttackScriptNotFound { attack: AttackKind },
    #[error("Attack script asset: {attack:?} not found")]
    AttackScriptAssetNotFound { attack: AttackKind },
}

pub fn check_interrupt_shared(state_context: &InterruptContext, attack_kind: AttackKind) -> Option<FighterState> {
    let state = GroundAttackState::create(attack_kind, state_context.attack_script_assets, state_context.attack_scripts);

    match state {
        Ok(state) => Some(FighterState::GroundAttack(state)),
        Err(create_error) => {
            error!("{}", create_error);
            None
        },
    }
}

pub fn check_interrupt(state_context: &InterruptContext) -> Option<FighterState> {
    if state_context
        .input
        .has_command(crate::input::FighterCommands::Attack)
    {
        let attack_kind = state_context
            .input
            .get_attack_command_type()
            .to_attack_kind_grounded();
        check_interrupt_shared(state_context, attack_kind)
    } else {
        None
    }
}

pub fn check_interrupt_dash_attack(state_context: &InterruptContext) -> Option<FighterState> {
    if state_context
        .input
        .has_command(crate::input::FighterCommands::Attack)
    {
        check_interrupt_shared(state_context, AttackKind::DashAttack)
    } else {
        None
    }
}