package chessboard

// Declare a type named Rank which stores if a square is occupied by a piece - this will be a slice of bools
// Declare a type named Chessboard contains a map of eight Ranks, accessed with values from "A" to "H"
type Rank []bool
type Chessboard map[string]Rank
// CountInRank returns how many squares are occupied in the chessboard,
// within the given rank
func CountInRank(cb Chessboard, rank string) int {
    sum := 0
    file, ok := cb[rank]
    if !ok {
        return 0 
    }
    for _, f := range file {
        if f {
            sum += 1
        }
    }
    return sum
}

// CountInFile returns how many squares are occupied in the chessboard,
// within the given file
func CountInFile(cb Chessboard, file int) int {
    if file < 1 || file > 8 {
        return 0
    }
    sum := 0
    for _, rank := range cb {
        if rank[file-1] {
            sum += 1
        }
    }
    return sum
}

// CountAll should count how many squares are present in the chessboard
func CountAll(cb Chessboard) int {
    sum := 0
    for _, rank := range cb {
        sum += len(rank)
    }

    return sum
}

// CountOccupied returns how many squares are occupied in the chessboard
func CountOccupied(cb Chessboard) int {
    sum := 0
    for name := range cb {
        sum += CountInRank(cb, name)
    }
    return sum
}