"""Round tube, any outside diameter, wall and length: EN 10305-1 precision steel tubes and EN 10220 tube sizes.

A hollow cylinder of outside diameter `diameter` (D) and wall thickness `wall` (T), its axis along +Z, one end face on
the XY plane centred on the origin. The bore is D - 2T. Dimensions are nominal; tolerances are not modelled.
"""
from steve import Model

diameter = 20  # mm Outside diameter D
wall = 2  # mm Wall thickness T
length = 1000  # mm Length
material = "steel"  # Material

# Standard sizes the presets use, "DxT": (standard and table, D, T), mm, nominal. The model takes any D and T.
SIZES = {
    "6x1": ("EN 10305-1 Table 5", 6, 1), "8x1": ("EN 10305-1 Table 5", 8, 1), "10x1": ("EN 10305-1 Table 5", 10, 1),
    "12x1.2": ("EN 10305-1 Table 5", 12, 1.2), "16x1.6": ("EN 10220 Table 1", 16, 1.6),
    "20x2": ("EN 10305-1 Table 5", 20, 2), "25x2.5": ("EN 10305-1 Table 5", 25, 2.5),
}
# material choice: (STEVE material library id, appearance colour)
MATERIALS = {
    "steel": ("steel-generic", "#8a8d91"),            # E235 (EN 10305-1)
    "stainless-304": ("stainless-304", "#c9ccd0"),    # EN 10088 1.4301
    "aluminium-6061": ("aluminum-6061-t6", "#d4d7db"),
}

if not 0 < 2 * wall < diameter:
    raise ValueError("The wall must be less than half the outside diameter.")
material_id, colour = MATERIALS[material]

model = Model()
with model.sketch("section", on="XY", name="Section") as sk:
    sk.circle("outside", (0, 0), diameter / 2)
    sk.circle("bore", (0, 0), diameter / 2 - wall)
model.extrude("tube", "section", distance=length, name="Tube")
model.material(material_id, color=colour)
result = model.result()