[
 {"note": "Offset had one distance and one direction, so there was no way to offset both sides of a curve in one operation. The window gains a Direction row of icon buttons carrying One Side, Two Sides and Symmetric, in the words solid.extrude already uses. Symmetric applies one distance each way. Two Sides adds an independent Distance 2 the other way."},
 {"start": "sketch.create"},
 {"click": {"plane": "XY"}},
 {"expect": {"sketching": true}},
 {"start": "sketch.circle.center"},
 {"click": {"sketch": [0, 0]}},
 {"click": {"sketch": [10, 0]}},
 {"key": "Escape"},
 {"expect": {"sketch_curves": {"own": 1}, "errors": 0}},

 {"note": "The window opens on One Side: Flip is offered, Distance 2 is not."},
 {"start": "sketch.offset"},
 {"click": {"sketch": [10, 0]}},
 {"expect": {"dialog": "Offset", "shown_handles": ["dialog:Direction", "dialog:Distance", "dialog:Flip", "dialog:Chain"], "hidden_handles": ["dialog:Distance 2"]}},

 {"note": "Symmetric offsets both sides, so Flip has no side left to swap and the row goes."},
 {"click": {"handle": "dialog:Direction:Symmetric"}},
 {"expect": {"dialog": "Offset", "shown_handles": ["dialog:Distance", "dialog:Chain"], "hidden_handles": ["dialog:Flip", "dialog:Distance 2"]}},

 {"note": "A 10 mm circle offset symmetrically by a typed 3 mm becomes a 7 mm circle and a 13 mm one, both about the same centre."},
 {"click": {"handle": "dialog:Distance"}},
 {"key": "A", "cmd": true},
 {"text": "3"},
 {"key": "Enter"},
 {"expect": {"dialog": null, "errors": 0, "sketch_curves": {"own": 3}}},
 {"expect": {"query": {"command": "sketch.inspect", "path": ["curves", 1, "radius"], "value": 7}}},
 {"expect": {"query": {"command": "sketch.inspect", "path": ["curves", 2, "radius"], "value": 13}}},
 {"shot": "sketch_offset_symmetric_circle"},
 {"start": "sketch.finish"},

 {"note": "Two Sides asks for the second distance, and Flip comes back: it decides which side each distance lands on."},
 {"start": "sketch.create"},
 {"click": {"plane": "XZ"}},
 {"start": "sketch.circle.center"},
 {"click": {"sketch": [0, 0]}},
 {"click": {"sketch": [10, 0]}},
 {"key": "Escape"},
 {"expect": {"sketch_curves": {"own": 1}, "errors": 0}},
 {"start": "sketch.offset"},
 {"click": {"sketch": [10, 0]}},
 {"click": {"handle": "dialog:Direction:Two Sides"}},
 {"expect": {"dialog": "Offset", "shown_handles": ["dialog:Distance", "dialog:Distance 2", "dialog:Flip", "dialog:Chain"]}},

 {"note": "Distance 3 inward and Distance 2 of 5 outward on the same 10 mm circle: a 7 mm circle and a 15 mm one."},
 {"click": {"handle": "dialog:Distance"}},
 {"key": "A", "cmd": true},
 {"text": "3"},
 {"click": {"handle": "dialog:Distance 2"}},
 {"key": "A", "cmd": true},
 {"text": "5"},
 {"key": "Enter"},
 {"expect": {"dialog": null, "errors": 0, "sketch_curves": {"own": 3}}},
 {"expect": {"query": {"command": "sketch.inspect", "path": ["curves", 1, "radius"], "value": 7}}},
 {"expect": {"query": {"command": "sketch.inspect", "path": ["curves", 2, "radius"], "value": 15}}},
 {"start": "sketch.finish"},

 {"note": "A whole chain offsets both ways at once: one picked edge of a 40 by 30 rectangle, symmetric by 5, gives a 30 by 20 chain inside and a 50 by 40 chain outside, four curves each."},
 {"start": "sketch.create"},
 {"click": {"plane": "YZ"}},
 {"start": "sketch.rectangle.two_point"},
 {"click": {"sketch": [0, 0]}},
 {"click": {"sketch": [40, 30]}},
 {"key": "Escape"},
 {"expect": {"sketch_curves": {"own": 4}, "errors": 0}},
 {"start": "sketch.offset"},
 {"click": {"sketch": [20, 0]}},
 {"click": {"handle": "dialog:Direction:Symmetric"}},
 {"click": {"handle": "dialog:Distance"}},
 {"key": "A", "cmd": true},
 {"text": "5"},
 {"key": "Enter"},
 {"expect": {"dialog": null, "errors": 0, "sketch_curves": {"own": 12}}},
 {"shot": "sketch_offset_symmetric_chain"},

 {"note": "Escape on a Two Sides window leaves the sketch exactly as it was."},
 {"start": "sketch.offset"},
 {"click": {"sketch": [20, 0]}},
 {"click": {"handle": "dialog:Direction:Two Sides"}},
 {"expect": {"dialog": "Offset"}},
 {"key": "Escape"},
 {"expect": {"dialog": null, "errors": 0, "sketch_curves": {"own": 12}}}
]