// and decompresses data according to the predictor algorithm
func Decompressor(reader io.Reader) io.Reader {
	var ctx context
	ctx.input = make([]byte, 0, 8)

	return decompressor(func(output []byte) (int, error) {
		var (
			err          error
			flags        byte
			i, rc, total int
		)

		// Sanity check for space to read into
		if len(output) == 0 {
			return 0, nil
		}

		// Check whether we have leftover data in the buffer
		if len(ctx.input) > 0 {
			rc = copy(output, ctx.input)

			// Check whether we still have leftover data in the buffer :)
			if rc < len(ctx.input) {
				ctx.input = ctx.input[:copy(ctx.input, ctx.input[rc:])]
			}
			return rc, nil
		}

	loop:
		// Read the flags
		rc, err = reader.Read(ctx.input[:1])
		if err != nil && err != io.EOF {
			return 0, err
		}
		if rc == 0 {
			return total, err
		}

		ctx.input = ctx.input[:8]
		flags = ctx.input[0]


		for i = 0; i < 8; i++ {
			if flags&(1<<uint(i)) > 0 {
				// Guess was right
				ctx.input[i] = ctx.table[ctx.hash]
			} else {
				rc, err = reader.Read(ctx.input[i:(i + 1)])

				if err == io.EOF {
					break
				}

				if err != nil {
					return total, err
				}

				if rc == 0 { // treat as EoF
					break
				}

				ctx.table[ctx.hash] = ctx.input[i]
			}

			ctx.hash = (ctx.hash << 4) ^ uint16(ctx.input[i])
		}

		rc = copy(output, ctx.input[:i])

		total += rc

		// Place any remaining bytes in the buffer
		if rc < i {
			ctx.input = ctx.input[:copy(ctx.input, ctx.input[rc:i])]
		} else {
			// Clear the buffer
			ctx.input = ctx.input[:0]

			// Advance the output buffer ...
			output = output[i:]
			// ... and decompress the next block if there is any space left
			if len(output) > 0 && err != io.EOF {
				goto loop
			}
		}

		return total, err
	})
}