Kuroshiro

Kuroshiro is a Japanese logic puzzle. Draw a single loop path in the grid that goes through all the black and white circles.

Rules: Draw a single closed line in the grid that does not pass through any cell more than once, but does not necessarily pass through all cells.
The individual sections of the line run horizontally or vertically between the centres of orthogonally adjacent cells.
The line must pass through all cells with white or black circles.
If two circles of the same colour follow each other on the line, the line must not turn in between. If two circles of different colours follow each other on the line, the line must turn off exactly once in between.