use std::fmt::Debug;
use std::sync::Arc;

use hashbrown::HashSet;

use crate::dynamic_data::choices::{MoveChoice, TurnChoice};
use crate::dynamic_data::Pokemon;
use crate::dynamic_data::{LearnedMove, MoveLearnMethod};
use crate::static_data::{MoveCategory, MoveData, MoveTarget, SecondaryEffect};
use crate::StringKey;

/// The misc library holds several misc functions required for the battle to run.
pub trait MiscLibrary<'library>: Debug {
    /// Returns whether or not a Pokemon is allowed to flee or switch out.
    fn can_flee(&self, choice: &TurnChoice) -> bool;
    /// Returns the move we need to use if we can't use another move. Typically Struggle.
    fn replacement_move<'func>(
        &'func self,
        user: &Arc<Pokemon<'func, 'library>>,
        target_side: u8,
        target_index: u8,
    ) -> TurnChoice<'func, 'library>;
    // TODO: can evolve from level up?
    // TODO: get time
}

/// A gen 7 implementation for the MiscLibrary.
#[derive(Debug)]
pub struct Gen7MiscLibrary<'library> {
    /// The move data for struggle. This is a pointer due to lifetime issues; we know that the
    /// learned move based on this has the same lifetime as the move data, but the compiler does not.
    /// If possible in a sane manner, we should get rid of this pointer.
    struggle_data: *const MoveData,
    /// The learned move data for struggle.
    struggle_learned_move: Arc<LearnedMove<'library>>,
}

impl<'library> Gen7MiscLibrary<'library> {
    /// Instantiates a new MiscLibrary.
    pub fn new() -> Self {
        let struggle_data = Box::new(MoveData::new(
            &StringKey::new("struggle"),
            0,
            MoveCategory::Physical,
            50,
            255,
            255,
            MoveTarget::Any,
            0,
            Some(SecondaryEffect::new(-1.0, StringKey::new("struggle"), vec![])),
            HashSet::new(),
        ));
        let struggle_ptr = Box::into_raw(struggle_data);
        let struggle_learned_move = Arc::new(LearnedMove::new(unsafe { &*struggle_ptr }, MoveLearnMethod::Unknown));
        Self {
            struggle_data: struggle_ptr,
            struggle_learned_move,
        }
    }
}

impl<'library> Default for Gen7MiscLibrary<'library> {
    fn default() -> Self {
        Self::new()
    }
}

impl<'library> Drop for Gen7MiscLibrary<'library> {
    fn drop(&mut self) {
        unsafe {
            Box::from_raw(self.struggle_data as *mut MoveData);
        }
    }
}

impl<'library> MiscLibrary<'library> for Gen7MiscLibrary<'library> {
    fn can_flee(&self, _choice: &TurnChoice) -> bool {
        todo!()
    }

    fn replacement_move<'func>(
        &'func self,
        user: &Arc<Pokemon<'func, 'library>>,
        target_side: u8,
        target_index: u8,
    ) -> TurnChoice<'func, 'library> {
        self.struggle_learned_move.restore_all_uses();
        TurnChoice::Move(MoveChoice::new(
            user.clone(),
            self.struggle_learned_move.clone(),
            target_side,
            target_index,
        ))
    }
}