package chess

import "mchess_server/types"

func (b *Board) GetNonBlockedRowAndColumn(fromSquare types.Coordinate) []types.Coordinate {
	squaresLeft := fromSquare.GetAllSquaresLeft()
	squaresRight := fromSquare.GetAllSquaresRight()
	squaresAbove := fromSquare.GetAllSquaresAbove()
	squaresBelow := fromSquare.GetAllSquaresBelow()
	nonBlocked := []types.Coordinate{}

    nonBlocked = append(nonBlocked, b.getNonBlocked(squaresLeft, fromSquare)...)
    nonBlocked = append(nonBlocked, b.getNonBlocked(squaresRight, fromSquare)...)
    nonBlocked = append(nonBlocked, b.getNonBlocked(squaresAbove, fromSquare)...)
    nonBlocked = append(nonBlocked, b.getNonBlocked(squaresBelow, fromSquare)...)

	return nonBlocked
}

func (b *Board) getNonBlocked(
    squaresToCheck []types.Coordinate, 
    sourceSquare types.Coordinate,
) []types.Coordinate {
	pieceOnSourceSquare := b.getPieceAt(sourceSquare)
    nonBlocked := []types.Coordinate{}

	for _, square := range squaresToCheck {
		piece := b.getPieceAt(square)
		if piece != nil {
			if piece.GetColor() == pieceOnSourceSquare.GetColor() {
				break
			}
			// if there is an opposite colored piece we append it but
			// stop appending the squares behind it
			nonBlocked = append(nonBlocked, square)
			break
		}
		nonBlocked = append(nonBlocked, square)
	}
    return nonBlocked
}