extern crate mcts;

use mcts::*;
use mcts::tree_policy::*;
use mcts::transposition_table::*;

#[derive(Clone)]
struct CountingGame(i64);

#[derive(Clone, Debug)]
enum Move {
    Add, Sub
}

impl GameState for CountingGame {
    type Move = Move;
    type Player = ();
    type MoveList = Vec<Self::Move>;

    fn current_player(&self) -> Self::Player {
        ()
    }

    fn available_moves(&self) -> Vec<Self::Move> {
        let x = self.0;
        if x == 100 {
            vec![]
        } else {
            vec![Move::Add, Move::Sub]
        }
    }

    fn make_move(&mut self, mov: &Self::Move) {
        match *mov {
            Move::Add => self.0 += 1,
            Move::Sub => self.0 -= 1,
        }
    }
}

impl TranspositionHash for CountingGame {
    fn hash(&self) -> u64 {
        self.0 as u64
    }
}

struct MyEvaluator;

impl Evaluator<MyMCTS> for MyEvaluator {
    type StateEvaluation = i64;

    fn evaluate_new_state(&self, state: &CountingGame, moves: &Vec<Move>,
        _: Option<SearchHandle<MyMCTS>>)
        -> (Vec<()>, i64) {
        (vec![(); moves.len()], state.0)
    }

    fn interpret_evaluation_for_player(&self, evaln: &i64, _player: &()) -> i64 {
        *evaln
    }

    fn evaluate_existing_state(&self, _: &CountingGame,  evaln: &i64, _: SearchHandle<MyMCTS>) -> i64 {
        *evaln
    }
}

#[derive(Default)]
struct MyMCTS;

impl MCTS for MyMCTS {
    type State = CountingGame;
    type Eval = MyEvaluator;
    type NodeData = ();
    type ExtraThreadData = ();
    type TreePolicy = UCTPolicy;
    type TranspositionTable = ApproxTable<Self>;

    fn virtual_loss(&self) -> i64 {
        500
    }
}

fn main() {
    let game = CountingGame(0);
    let mut mcts = MCTSManager::new(game, MyMCTS, MyEvaluator, UCTPolicy::new(5.0),
        ApproxTable::new(1024));
    mcts.playout_n(100000);
    let pv: Vec<_> = mcts.principal_variation_states(10).into_iter().map(|x| x.0).collect();
    println!("Principal variation: {:?}", pv);
    println!("Evaluation of moves:");
    mcts.tree().debug_moves();
}