use std::{str::Chars, fmt::Display};

use crate::{square::Square, bitboard::BitboardFns, board::piece::Piece};

#[derive(Debug, Clone, PartialEq, Eq, Copy)]
pub enum MoveKind {
    Quiet,
    Capture,
    Castle,
    EnPassant,
    DoublePush,
    Promotion(Piece),
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub struct Move {
    pub source: Square,
    pub target: Square,
    pub kind: MoveKind,
}

impl Move {
    pub fn print(&self) {
        let bb = self.source.to_bitboard() | self.target.to_bitboard();
        bb.print(format!("{:?}", self).as_str());
    }

    /// Tactical move is a move that changes material score
    pub fn is_tactical(&self) -> bool {
        matches!(self.kind, MoveKind::Capture | MoveKind::EnPassant | MoveKind::Promotion(_))
    }

    pub fn from_notation(mut notation: Chars) -> Self {
        let source = Square::from_notation(&mut notation).unwrap();
        let target = Square::from_notation(&mut notation).unwrap();

        if let Some(promotion) = notation.next() {
            let piece = match promotion {
                'r' => Piece::Rook,
                'q' => Piece::Queen,
                'b' => Piece::Bishop,
                'n' => Piece::Knight,
                _ => panic!("Illegal promotion piece: {:?}", promotion)
            };
            return Move { source, target, kind: MoveKind::Promotion(piece) }
        }
        Move { source, target, kind: MoveKind::Quiet }
    }
}

impl Display for Move {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        let promotion_postfix = match self.kind {
            MoveKind::Promotion(piece) => {
                match piece.without_color() {
                    Piece::Rook => "r",
                    Piece::Queen => "q",
                    Piece::Bishop => "b",
                    Piece::Knight => "n",
                    _ => panic!("Illegal promotion piece: {:?}", piece)
                }
            }
            _ => ""
        };
        write!(f, "{}{}{}", self.source, self.target, promotion_postfix)
    }
}