agent-tk 0.4.0

//! Support for converting Tst via a recursive mapping process. It is especially useful for expanding TSTs.
use futures::FutureExt;
use std::{marker::PhantomData, sync::RwLock};

use crate::{definitions, Error, Result};

//  __  __
// |  \/  | __ _ _ __  _ __   ___ _ __ ___
// | |\/| |/ _` | '_ \| '_ \ / _ \ '__/ __|
// | |  | | (_| | |_) | |_) |  __/ |  \__ \
// |_|  |_|\__,_| .__/| .__/ \___|_|  |___/
//              |_|   |_|

/// Trait representing the mappers for each type of tree node
pub trait Mappers: Sync
{
  /// Result of the mapping
  type Output;
  /// Map a noop node
  fn map_noop<'a>(
    &'a self,
    tst_node: definitions::tst::Noop,
  ) -> futures::future::BoxFuture<'a, Result<Self::Output>>;
  /// Map a sequential node
  fn map_seq<'a>(
    &'a self,
    tst_node: definitions::tst::Seq,
  ) -> futures::future::BoxFuture<'a, Result<Self::Output>>;
  /// Map a concurrent node
  fn map_conc<'a>(
    &'a self,
    tst_node: definitions::tst::Conc,
  ) -> futures::future::BoxFuture<'a, Result<Self::Output>>;
  /// Map a move to node
  fn map_move_to<'a>(
    &'a self,
    tst_node: definitions::tst::MoveTo,
  ) -> futures::future::BoxFuture<'a, Result<Self::Output>>;
  /// Map a search area node
  fn map_search_area<'a>(
    &'a self,
    tst_node: definitions::tst::SearchArea,
  ) -> futures::future::BoxFuture<'a, Result<Self::Output>>;
}

//  __  __
// |  \/  | __ _ _ __  _ __   ___ _ __
// | |\/| |/ _` | '_ \| '_ \ / _ \ '__|
// | |  | | (_| | |_) | |_) |  __/ |
// |_|  |_|\__,_| .__/| .__/ \___|_|
//              |_|   |_|

/// Mapper trait
pub trait Mapper<TInput, TOutput>: Send + Sync
{
  /// Map the node t
  fn map<'a, 'b, M>(
    &'a self,
    mappers: &'b M,
    t: TInput,
  ) -> futures::future::BoxFuture<'b, Result<TOutput>>
  where
    M: Mappers<Output = TOutput> + Send,
    TInput: 'b;
}

// Dispatch

fn dispatch_mapping<'a, M>(
  mappers: &'a M,
  tst_node: definitions::tst::Node,
) -> futures::future::BoxFuture<'a, Result<M::Output>>
where
  M: Mappers,
{
  match tst_node
  {
    definitions::tst::Node::Noop(noop) => mappers.map_noop(noop),
    definitions::tst::Node::Seq(seq) => mappers.map_seq(seq),
    definitions::tst::Node::Conc(conc) => mappers.map_conc(conc),
    definitions::tst::Node::MoveTo(move_to) => mappers.map_move_to(move_to),
    definitions::tst::Node::SearchArea(search_area) => mappers.map_search_area(search_area),
  }
}

//     _                                  _       _
//    / \   ___ ___ _   _ _ __ ___  _   _| | __ _| |_ ___  _ __
//   / _ \ / __/ __| | | | '_ ` _ \| | | | |/ _` | __/ _ \| '__|
//  / ___ \ (_| (__| |_| | | | | | | |_| | | (_| | || (_) | |
// /_/   \_\___\___|\__,_|_| |_| |_|\__,_|_|\__,_|\__\___/|_|

/// Accumulator used by SeqMapper and ConcMapper
pub trait Accumulator<T>
{
  /// Start a new accumulator
  fn new() -> Self;
  /// Accumulate the next value
  fn next(&mut self, t: T) -> Result<()>;
  /// Finalise the accumulation
  fn finalise(self) -> Result<T>;
}

//   ____                                _ _       _   _           _      __  __
//  / ___|___  _ __ ___  _ __   ___  ___(_) |_ ___| \ | | ___   __| | ___|  \/  | __ _ _ __  _ __   ___ _ __
// | |   / _ \| '_ ` _ \| '_ \ / _ \/ __| | __/ _ \  \| |/ _ \ / _` |/ _ \ |\/| |/ _` | '_ \| '_ \ / _ \ '__|
// | |__| (_) | | | | | | |_) | (_) \__ \ | ||  __/ |\  | (_) | (_| |  __/ |  | | (_| | |_) | |_) |  __/ |
//  \____\___/|_| |_| |_| .__/ \___/|___/_|\__\___|_| \_|\___/ \__,_|\___|_|  |_|\__,_| .__/| .__/ \___|_|
//                      |_|                                                           |_|   |_|

/// Generic Mapper for composite node with children
#[derive(Default)]
pub struct CompositeNodeMapper<TOutput, TAccumulator: Accumulator<TOutput>>
{
  _out: PhantomData<fn() -> TOutput>,
  _acc: PhantomData<fn() -> TAccumulator>,
}

impl<TNode, TOutput, TAccumulator> Mapper<TNode, TOutput>
  for CompositeNodeMapper<TOutput, TAccumulator>
where
  TNode: definitions::tst::CompositeNode
    + Send
    + IntoIterator<Item = definitions::tst::Node, IntoIter: Send>,
  TAccumulator: Accumulator<TOutput> + Send,
{
  fn map<'a, 'b, M>(
    &'a self,
    mappers: &'b M,
    t: TNode,
  ) -> futures::future::BoxFuture<'b, Result<M::Output>>
  where
    M: Mappers<Output = TOutput>,
    TNode: 'b,
  {
    async move {
      let mut acc = TAccumulator::new();
      for sub_task in t.into_iter()
      {
        acc.next(dispatch_mapping(mappers, sub_task).await?)?;
      }
      acc.finalise()
    }
    .boxed()
  }
}

//  ___    _            _   _ _         __  __
// |_ _|__| | ___ _ __ | |_(_) |_ _   _|  \/  | __ _ _ __  _ __   ___ _ __
//  | |/ _` |/ _ \ '_ \| __| | __| | | | |\/| |/ _` | '_ \| '_ \ / _ \ '__|
//  | | (_| |  __/ | | | |_| | |_| |_| | |  | | (_| | |_) | |_) |  __/ |
// |___\__,_|\___|_| |_|\__|_|\__|\__, |_|  |_|\__,_| .__/| .__/ \___|_|
//                                |___/             |_|   |_|

/// Mapper that output the node, unchanged.
#[derive(Default)]
pub struct IdentityMapper {}

impl<TNode> Mapper<TNode, definitions::tst::Node> for IdentityMapper
where
  TNode: definitions::tst::NodeTrait + Send,
{
  fn map<'a, 'b, M>(
    &'a self,
    _mappers: &'b M,
    t: TNode,
  ) -> futures::future::BoxFuture<'b, Result<definitions::tst::Node>>
  where
    M: Mappers<Output = definitions::tst::Node>,
    TNode: 'b,
  {
    std::future::ready(Ok(t.into())).boxed()
  }
}

//  _____              __  __                            _____          _ _
// |_   _| __ ___  ___|  \/  | __ _ _ __  _ __   ___ _ _|_   _| __ __ _(_) |_
//   | || '__/ _ \/ _ \ |\/| |/ _` | '_ \| '_ \ / _ \ '__|| || '__/ _` | | __|
//   | || | |  __/  __/ |  | | (_| | |_) | |_) |  __/ |   | || | | (_| | | |_
//   |_||_|  \___|\___|_|  |_|\__,_| .__/| .__/ \___|_|   |_||_|  \__,_|_|\__|
//                                 |_|   |_|

/// Base trait for a TreeMapper
pub trait TreeMapperTrait<TOutput>
{
  /// Mapper for sequential nodes
  type SeqMapper: Mapper<definitions::tst::Seq, TOutput>;
  /// Mapper for concurrent nodes
  type ConcMapper: Mapper<definitions::tst::Conc, TOutput>;
  /// Mapper for move_to nodes
  type MoveToMapper: Mapper<definitions::tst::MoveTo, TOutput>;
  /// Mapper for search area nodes
  type SearchAreaMapper: Mapper<definitions::tst::SearchArea, TOutput>;

  /// Map the tst
  fn map<'a>(
    &'a self,
    t: definitions::tst::Node,
  ) -> futures::future::BoxFuture<'a, Result<TOutput>>;

  /// Map the tst and block
  fn map_direct(&self, t: definitions::tst::Node) -> Result<TOutput>
  {
    futures::executor::block_on(self.map(t))
  }
}

//  _____              __  __
// |_   _| __ ___  ___|  \/  | __ _ _ __  _ __   ___ _ __
//   | || '__/ _ \/ _ \ |\/| |/ _` | '_ \| '_ \ / _ \ '__|
//   | || | |  __/  __/ |  | | (_| | |_) | |_) |  __/ |
//   |_||_|  \___|\___|_|  |_|\__,_| .__/| .__/ \___|_|
//                                 |_|   |_|

/// Implementation of mapping for a tree
pub struct TreeMapper<
  TOutput,
  TNoopMapper: Mapper<definitions::tst::Noop, TOutput>,
  TSeqMapper: Mapper<definitions::tst::Seq, TOutput>,
  TConcMapper: Mapper<definitions::tst::Conc, TOutput>,
  TMoveToMapper: Mapper<definitions::tst::MoveTo, TOutput>,
  TSearchAreaMapper: Mapper<definitions::tst::SearchArea, TOutput>,
> {
  noop_mapper: TNoopMapper,
  seq_mapper: TSeqMapper,
  conc_mapper: TConcMapper,
  move_to_mapper: TMoveToMapper,
  search_area_mapper: TSearchAreaMapper,
  _out: PhantomData<fn() -> TOutput>,
}

impl<TOutput, TNoopMapper, TSeqMapper, TConcMapper, TMoveToMapper, TSearchAreaMapper> Mappers
  for TreeMapper<TOutput, TNoopMapper, TSeqMapper, TConcMapper, TMoveToMapper, TSearchAreaMapper>
where
  TNoopMapper: Mapper<definitions::tst::Noop, TOutput>,
  TSeqMapper: Mapper<definitions::tst::Seq, TOutput>,
  TConcMapper: Mapper<definitions::tst::Conc, TOutput>,
  TMoveToMapper: Mapper<definitions::tst::MoveTo, TOutput>,
  TSearchAreaMapper: Mapper<definitions::tst::SearchArea, TOutput>,
{
  type Output = TOutput;
  fn map_noop<'a>(
    &'a self,
    tst_node: definitions::tst::Noop,
  ) -> futures::future::BoxFuture<'a, Result<Self::Output>>
  {
    self.noop_mapper.map(self, tst_node)
  }
  fn map_seq<'a>(
    &'a self,
    tst_node: definitions::tst::Seq,
  ) -> futures::future::BoxFuture<'a, Result<Self::Output>>
  {
    self.seq_mapper.map(self, tst_node)
  }
  fn map_conc<'a>(
    &'a self,
    tst_node: definitions::tst::Conc,
  ) -> futures::future::BoxFuture<'a, Result<Self::Output>>
  {
    self.conc_mapper.map(self, tst_node)
  }
  fn map_move_to<'a>(
    &'a self,
    tst_node: definitions::tst::MoveTo,
  ) -> futures::future::BoxFuture<'a, Result<Self::Output>>
  {
    self.move_to_mapper.map(self, tst_node)
  }
  fn map_search_area<'a>(
    &'a self,
    tst_node: definitions::tst::SearchArea,
  ) -> futures::future::BoxFuture<'a, Result<Self::Output>>
  {
    self.search_area_mapper.map(self, tst_node)
  }
}

impl<TOutput, TNoopMapper, TSeqMapper, TConcMapper, TMoveToMapper, TSearchAreaMapper>
  TreeMapperTrait<TOutput>
  for TreeMapper<TOutput, TNoopMapper, TSeqMapper, TConcMapper, TMoveToMapper, TSearchAreaMapper>
where
  TNoopMapper: Mapper<definitions::tst::Noop, TOutput>,
  TSeqMapper: Mapper<definitions::tst::Seq, TOutput>,
  TConcMapper: Mapper<definitions::tst::Conc, TOutput>,
  TMoveToMapper: Mapper<definitions::tst::MoveTo, TOutput>,
  TSearchAreaMapper: Mapper<definitions::tst::SearchArea, TOutput>,
{
  type SeqMapper = TSeqMapper;
  type ConcMapper = TConcMapper;
  type MoveToMapper = TMoveToMapper;
  type SearchAreaMapper = TSearchAreaMapper;
  /// Map the tst
  fn map<'a>(&'a self, t: definitions::tst::Node)
    -> futures::future::BoxFuture<'a, Result<TOutput>>
  {
    dispatch_mapping(self, t)
  }
}

impl<TOutput, TNoopMapper, TSeqMapper, TConcMapper, TMoveToMapper, TSearchAreaMapper> Default
  for TreeMapper<TOutput, TNoopMapper, TSeqMapper, TConcMapper, TMoveToMapper, TSearchAreaMapper>
where
  TNoopMapper: Mapper<definitions::tst::Noop, TOutput> + Default + Send,
  TSeqMapper: Mapper<definitions::tst::Seq, TOutput> + Default + Send,
  TConcMapper: Mapper<definitions::tst::Conc, TOutput> + Default + Send,
  TMoveToMapper: Mapper<definitions::tst::MoveTo, TOutput> + Default + Send,
  TSearchAreaMapper: Mapper<definitions::tst::SearchArea, TOutput> + Default + Send,
{
  fn default() -> Self
  {
    Self {
      noop_mapper: Default::default(),
      seq_mapper: Default::default(),
      conc_mapper: Default::default(),
      move_to_mapper: Default::default(),
      search_area_mapper: Default::default(),
      _out: Default::default(),
    }
  }
}

//  _____                     __                                 _                                  _       _
// |_   _| __ __ _ _ __  ___ / _| ___  _ __ _ __ ___   ___ _ __ / \   ___ ___ _   _ _ __ ___  _   _| | __ _| |_ ___  _ __
//   | || '__/ _` | '_ \/ __| |_ / _ \| '__| '_ ` _ \ / _ \ '__/ _ \ / __/ __| | | | '_ ` _ \| | | | |/ _` | __/ _ \| '__|
//   | || | | (_| | | | \__ \  _| (_) | |  | | | | | |  __/ | / ___ \ (_| (__| |_| | | | | | | |_| | | (_| | || (_) | |
//   |_||_|  \__,_|_| |_|___/_|  \___/|_|  |_| |_| |_|\___|_|/_/   \_\___\___|\__,_|_| |_| |_|\__,_|_|\__,_|\__\___/|_|
//

/// Accumulator for transform operations.
pub struct TransformerAccumulator<TNode: definitions::tst::CompositeNode>
{
  children: RwLock<Option<Vec<definitions::tst::Node>>>,
  tnode: PhantomData<fn() -> TNode>,
}

impl<TNode> Default for TransformerAccumulator<TNode>
where
  TNode: definitions::tst::CompositeNode,
{
  fn default() -> Self
  {
    Self::new()
  }
}

impl<TNode> Accumulator<definitions::tst::Node> for TransformerAccumulator<TNode>
where
  TNode: definitions::tst::CompositeNode,
{
  fn new() -> Self
  {
    Self {
      children: RwLock::new(Some(Default::default())),
      tnode: Default::default(),
    }
  }
  fn next(&mut self, t: definitions::tst::Node) -> Result<()>
  {
    let _: () = self
      .children
      .write()?
      .as_mut()
      .ok_or(Error::InternalError("Null vector should not happen."))?
      .push(t);
    Ok(())
  }
  fn finalise(self) -> Result<definitions::tst::Node>
  {
    let mut builder = TNode::build(Default::default());
    for c in self
      .children
      .write()?
      .take()
      .ok_or(Error::InternalError("Null vector should not happen."))?
      .into_iter()
    {
      builder = builder.add_node(c);
    }
    Ok(builder.into())
  }
}

//  _____             _____                     __
// |_   _| __ ___  __|_   _| __ __ _ _ __  ___ / _| ___  _ __ _ __ ___   ___ _ __
//   | || '__/ _ \/ _ \| || '__/ _` | '_ \/ __| |_ / _ \| '__| '_ ` _ \ / _ \ '__|
//   | || | |  __/  __/| || | | (_| | | | \__ \  _| (_) | |  | | | | | |  __/ |
//   |_||_|  \___|\___||_||_|  \__,_|_| |_|___/_|  \___/|_|  |_| |_| |_|\___|_|
//

/// A mapper that transform a tree. Can be used for instance to transform nodes that do not have an executor
pub type TreeTransformer<TSeqMapper, TConcMapper, TMoveToMapper, TSearchAreaMapper> = TreeMapper<
  definitions::tst::Node,
  IdentityMapper,
  TSeqMapper,
  TConcMapper,
  TMoveToMapper,
  TSearchAreaMapper,
>;

/// Tree transformer with default transformers for Seq/Conc
pub type DefaultTreeTransformer<TMoveToMapper, TSearchAreaMapper> = TreeTransformer<
  CompositeNodeMapper<definitions::tst::Node, TransformerAccumulator<definitions::tst::Seq>>,
  CompositeNodeMapper<definitions::tst::Node, TransformerAccumulator<definitions::tst::Conc>>,
  TMoveToMapper,
  TSearchAreaMapper,
>;

impl<TMoveToMapper, TSearchAreaMapper> DefaultTreeTransformer<TMoveToMapper, TSearchAreaMapper>
where
  TMoveToMapper: Mapper<definitions::tst::MoveTo, definitions::tst::Node> + Send,
  TSearchAreaMapper: Mapper<definitions::tst::SearchArea, definitions::tst::Node> + Send,
{
  /// Create a new default tree transformer with the given node mappers
  pub fn new(move_to_mapper: TMoveToMapper, search_area_mapper: TSearchAreaMapper) -> Self
  {
    Self {
      noop_mapper: IdentityMapper {},
      seq_mapper: Default::default(),
      conc_mapper: Default::default(),
      move_to_mapper,
      search_area_mapper,
      _out: Default::default(),
    }
  }
}

#[cfg(test)]
mod tests
{
  use super::*;
  macro_rules! get_tst_node {
    ($value:expr, $variant:path) => {
      match $value
      {
        $variant(x) => x,
        _ => panic!("Unexpected TST Node."),
      }
    };
  }
  #[derive(Default)]
  struct FakeSearchAreaTransformer {}

  impl Mapper<definitions::tst::SearchArea, definitions::tst::Node> for FakeSearchAreaTransformer
  {
    fn map<'a, 'b, M>(
      &'a self,
      _mappers: &'b M,
      t: definitions::tst::SearchArea,
    ) -> futures::future::BoxFuture<'b, Result<definitions::tst::Node>>
    where
      M: Mappers<Output = definitions::tst::Node> + Send,
      definitions::tst::SearchArea: 'b,
    {
      let avg = t.params.area.iter().fold((0.0, 0.0), |acc, x| {
        (acc.0 + x.longitude, acc.1 + x.latitude)
      });
      std::future::ready(Ok(
        definitions::tst::MoveTo {
          params: definitions::tst::MoveToParameters {
            waypoint: definitions::tst::GeoPoint {
              longitude: avg.0 / t.params.area.len() as f64,
              latitude: avg.1 / t.params.area.len() as f64,
              altitude: 0.0,
            },
            ..Default::default()
          },
          ..Default::default()
        }
        .into(),
      ))
      .boxed()
    }
  }

  #[test]
  fn expansion()
  {
    let node: definitions::tst::Node = definitions::tst::Seq::build(None)
      .add(
        definitions::tst::SearchAreaParameters {
          area: vec![
            definitions::tst::GeoPoint {
              longitude: 10.0,
              latitude: 50.0,
              altitude: 0.0,
            },
            definitions::tst::GeoPoint {
              longitude: 12.0,
              latitude: 50.0,
              altitude: 0.0,
            },
            definitions::tst::GeoPoint {
              longitude: 12.0,
              latitude: 52.0,
              altitude: 0.0,
            },
            definitions::tst::GeoPoint {
              longitude: 10.0,
              latitude: 52.0,
              altitude: 0.0,
            },
          ],
          ..Default::default()
        },
        None,
      )
      .into();
    let transformer: DefaultTreeTransformer<IdentityMapper, FakeSearchAreaTransformer> =
      Default::default();
    let transformed_node = transformer.map_direct(node).unwrap();
    let node_seq = get_tst_node!(transformed_node, definitions::tst::Node::Seq);
    let move_to = get_tst_node!(&node_seq.children[0], definitions::tst::Node::MoveTo);
    assert_eq!(move_to.params.waypoint.longitude, 11.0);
    assert_eq!(move_to.params.waypoint.latitude, 51.0);
  }
}