use std::time::Duration;

use bevy::prelude::*;

use super::{FighterStateContext, FighterStateImpl, ground, walk};
use crate::fighter::animation::AnimKind;
use crate::fighter::state::fall::FallState;
use crate::fighter::state::ground::{
    GroundedMotionResult, GroundedStateCommon, grounded_movement_common_interrupts,
};
use crate::fighter::state::{FighterState, dash, turn};

#[derive(Debug, Clone, Hash)]
pub struct WaitState {
    pub grounded_common: GroundedStateCommon,
}

impl FighterStateImpl for WaitState {
    const NAME: &'static str = "Wait";
    fn check_interrupt(&self, state_context: &mut FighterStateContext) -> Option<FighterState> {
        if let Some(state) = ground::grounded_movement_standstill_common_interrupts(
            state_context,
            &self.grounded_common,
        ) {
            // Prevent transitioning into myself
            if let FighterState::Wait(_) = state {
                None
            } else {
                Some(state)
            }
        } else if let Some(state) =
            ground::grounded_movement_common_interrupts(state_context, &self.grounded_common)
        {
            Some(state)
        } else {
            None
        }
    }

    fn on_enter(&mut self, state_context: &mut super::FighterStateContext) {
        state_context.play_animation(AnimKind::Wait, true);
    }

    fn update(&mut self, state_context: &mut super::FighterStateContext) {
        let friction = if state_context.velocity.x.abs()
            > state_context.fighter_manifest.attributes.max_walk_vel
        {
            state_context.fighter_manifest.attributes.ground_friction
                * state_context
                    .game_settings
                    .fighter_common
                    .ground_friction_over_walk_speed_multiplier
        } else {
            state_context.fighter_manifest.attributes.ground_friction
        };

        let ground_velocity = state_context.velocity.x;

        state_context.velocity.x += ground::apply_grounded_friction(friction, ground_velocity);

        ground::apply_grounded_motion(
            state_context.velocity,
            state_context.translation,
            state_context.prev_translation,
        );
    }

    fn check_collision_interrupt(
        &mut self,
        state_context: &mut FighterStateContext,
    ) -> Option<FighterState> {
        if let GroundedMotionResult::InAir =
            ground::collide_with_stage_grounded(state_context, &mut self.grounded_common, false)
        {
            Some(FighterState::Fall(FallState))
        } else {
            None
        }
    }
}

pub fn check_input(
    state_context: &FighterStateContext,
    ground_state_common: &GroundedStateCommon,
) -> Option<FighterState> {
    let input_frame = state_context.input.get_last_frame();

    if input_frame.movement.x.abs() < state_context.game_settings.input_common.stick_deadzone {
        return Some(FighterState::Wait(WaitState {
            grounded_common: ground_state_common.clone(),
        }));
    }
    None
}