func ParseTilePath()

in sumdb/tlog/tile.go [192:234]

• 43 lines of code
• 15 McCabe index (conditional complexity)

func ParseTilePath(path string) (Tile, error) {
	f := strings.Split(path, "/")
	if len(f) < 4 || f[0] != "tile" {
		return Tile{}, &badPathError{path}
	}
	h, err1 := strconv.Atoi(f[1])
	isData := false
	if f[2] == "data" {
		isData = true
		f[2] = "0"
	}
	l, err2 := strconv.Atoi(f[2])
	if err1 != nil || err2 != nil || h < 1 || l < 0 || h > 30 {
		return Tile{}, &badPathError{path}
	}
	w := 1 << uint(h)
	if dotP := f[len(f)-2]; strings.HasSuffix(dotP, ".p") {
		ww, err := strconv.Atoi(f[len(f)-1])
		if err != nil || ww <= 0 || ww >= w {
			return Tile{}, &badPathError{path}
		}
		w = ww
		f[len(f)-2] = dotP[:len(dotP)-len(".p")]
		f = f[:len(f)-1]
	}
	f = f[3:]
	n := int64(0)
	for _, s := range f {
		nn, err := strconv.Atoi(strings.TrimPrefix(s, "x"))
		if err != nil || nn < 0 || nn >= pathBase {
			return Tile{}, &badPathError{path}
		}
		n = n*pathBase + int64(nn)
	}
	if isData {
		l = -1
	}
	t := Tile{H: h, L: l, N: n, W: w}
	if path != t.Path() {
		return Tile{}, &badPathError{path}
	}
	return t, nil
}