fn __zero_std_path_is_sep(byte: u8) -> Bool {
    return byte == 47_u8 || byte == 92_u8
}

fn __zero_std_path_segment_end(path: String, index: usize) -> Bool {
    return index >= std.mem.len(path) || __zero_std_path_is_sep(path[index])
}

fn __zero_std_path_trim_end(path: String) -> usize {
    var end: usize = std.mem.len(path)
    while end > 0 && __zero_std_path_is_sep(path[end - 1]) {
        end = end - 1
    }
    return end
}

fn __zero_std_path_basename(path: String) -> String {
    let end: usize = __zero_std_path_trim_end(path)
    var start: usize = end
    while start > 0 && !__zero_std_path_is_sep(path[start - 1]) {
        start = start - 1
    }
    return path[start..end]
}

fn __zero_std_path_dirname(path: String) -> String {
    let end: usize = __zero_std_path_trim_end(path)
    var root_len: usize = 0
    if std.mem.len(path) > 0 && __zero_std_path_is_sep(path[0]) {
        root_len = 1
    }
    if root_len > 0 && end == 0 {
        return path[..root_len]
    }
    var split: usize = end
    while split > 0 && !__zero_std_path_is_sep(path[split - 1]) {
        split = split - 1
    }
    while split > root_len && __zero_std_path_is_sep(path[split - 1]) {
        split = split - 1
    }
    return path[..split]
}

fn __zero_std_path_extension(path: String) -> String {
    let end: usize = __zero_std_path_trim_end(path)
    var start: usize = end
    while start > 0 && !__zero_std_path_is_sep(path[start - 1]) {
        start = start - 1
    }
    var dot: usize = end
    var scan: usize = end
    while scan > start {
        scan = scan - 1
        if path[scan] == 46_u8 {
            dot = scan
            scan = start
        }
    }
    if dot == end {
        return path[end..end]
    }
    if dot == start {
        return path[end..end]
    }
    return path[dot + 1..end]
}

fn __zero_std_path_copy(buffer: MutSpan<u8>, source: String) -> Maybe<String> {
    let len: usize = std.mem.len(source)
    if len > std.mem.len(buffer) {
        return null
    }
    var index: usize = 0
    while index < len {
        buffer[index] = source[index]
        index = index + 1
    }
    return buffer[..len]
}

fn __zero_std_path_join(buffer: MutSpan<u8>, left: String, right: String) -> Maybe<String> {
    var left_end: usize = __zero_std_path_trim_end(left)
    if left_end == 0 && (std.mem.len(left) > 0 && __zero_std_path_is_sep(left[0])) {
        left_end = 1
    }
    let left_is_root: Bool = left_end == 1 && __zero_std_path_is_sep(left[0])
    let right_is_root: Bool = std.mem.len(right) > 0 && __zero_std_path_is_sep(right[0])
    var right_start: usize = 0
    while right_start < std.mem.len(right) && __zero_std_path_is_sep(right[right_start]) {
        right_start = right_start + 1
    }
    let right_len: usize = std.mem.len(right) - right_start
    var total: usize = left_end + right_len
    if left_end == 0 && right_is_root {
        total = total + 1
    }
    if left_end > 0 && right_len > 0 && !left_is_root {
        total = total + 1
    }
    if total > std.mem.len(buffer) {
        return null
    }
    var out: usize = 0
    while out < left_end {
        if left_is_root && out == 0 {
            buffer[out] = 47_u8
        } else {
            buffer[out] = left[out]
        }
        out = out + 1
    }
    if left_end == 0 && right_is_root {
        buffer[out] = 47_u8
        out = out + 1
    }
    if left_end > 0 && right_len > 0 && !left_is_root {
        buffer[out] = 47_u8
        out = out + 1
    }
    var read: usize = right_start
    while read < std.mem.len(right) {
        buffer[out] = right[read]
        out = out + 1
        read = read + 1
    }
    return buffer[..out]
}

fn __zero_std_path_output_ends_parent(buffer: MutSpan<u8>, out: usize, root_len: usize) -> Bool {
    if out <= root_len {
        return false
    }
    var segment_start: usize = out
    while segment_start > root_len && !__zero_std_path_is_sep(buffer[segment_start - 1]) {
        segment_start = segment_start - 1
    }
    let segment_len: usize = out - segment_start
    if segment_len != 2 {
        return false
    }
    return buffer[segment_start] == 46_u8 && buffer[segment_start + 1] == 46_u8
}

fn __zero_std_path_normalize(buffer: MutSpan<u8>, path: String) -> Maybe<String> {
    var read: usize = 0
    var out: usize = 0
    var root_len: usize = 0
    if std.mem.len(path) > 0 && __zero_std_path_is_sep(path[0]) {
        if std.mem.len(buffer) == 0 {
            return null
        }
        buffer[0] = 47_u8
        out = 1
        root_len = 1
        read = 1
    }
    while read < std.mem.len(path) {
        while read < std.mem.len(path) && __zero_std_path_is_sep(path[read]) {
            read = read + 1
        }
        if read < std.mem.len(path) {
            let segment_start: usize = read
            while read < std.mem.len(path) && !__zero_std_path_is_sep(path[read]) {
                read = read + 1
            }
            let segment_end: usize = read
            let segment_len: usize = segment_end - segment_start
            if segment_len == 1 && path[segment_start] == 46_u8 {
                read = segment_end
            } else if segment_len == 2 && path[segment_start] == 46_u8 && path[segment_start + 1] == 46_u8 {
                if root_len == 1 && out == root_len {
                    read = segment_end
                } else if out > root_len && !__zero_std_path_output_ends_parent(buffer, out, root_len) {
                    while out > root_len && !__zero_std_path_is_sep(buffer[out - 1]) {
                        out = out - 1
                    }
                    if out > root_len && __zero_std_path_is_sep(buffer[out - 1]) {
                        out = out - 1
                    }
                } else {
                    var needed: usize = segment_len
                    if out > root_len {
                        needed = needed + 1
                    }
                    if out + needed > std.mem.len(buffer) {
                        return null
                    }
                    if out > root_len {
                        buffer[out] = 47_u8
                        out = out + 1
                    }
                    var copy: usize = segment_start
                    while copy < segment_end {
                        buffer[out] = path[copy]
                        out = out + 1
                        copy = copy + 1
                    }
                }
            } else {
                var needed: usize = segment_len
                if out > root_len {
                    needed = needed + 1
                }
                if out + needed > std.mem.len(buffer) {
                    return null
                }
                if out > root_len {
                    buffer[out] = 47_u8
                    out = out + 1
                }
                var copy: usize = segment_start
                while copy < segment_end {
                    buffer[out] = path[copy]
                    out = out + 1
                    copy = copy + 1
                }
            }
        }
    }
    return buffer[..out]
}

fn __zero_std_path_relative(buffer: MutSpan<u8>, base: String, target: String) -> Maybe<String> {
    let base_end: usize = __zero_std_path_trim_end(base)
    let target_len: usize = std.mem.len(target)
    let base_prefix: String = base[..base_end]
    let base_matches: Bool = std.str.startsWith(target, base_prefix)
    if base_matches && base_end == target_len {
        return buffer[..0]
    }
    if base_matches && base_end < target_len {
        if __zero_std_path_is_sep(target[base_end]) {
            var out: usize = 0
            var read: usize = base_end + 1
            let rel_len: usize = target_len - read
            if rel_len > std.mem.len(buffer) {
                return null
            }
            while read < target_len {
                buffer[out] = target[read]
                out = out + 1
                read = read + 1
            }
            return buffer[..out]
        }
    }
    return __zero_std_path_copy(buffer, target)
}