from cad_shapes import *

mm_inch = 25.4
scale_factor = 1.0

def inchn(x):
    return mm_inch * x

def inch(x):
    return scale_factor * mm_inch * x

def wslot(x, y, width, height, angle = 0, chamfer = 0.2):
    slot = rectangle(-width/2, width/2, -height, 0)
    inset = triangle(width/2, 0,
                     width/2 + width * chamfer, 0,
                     width/2, -chamfer*width)
    inset = add(inset, reflect_x(inset))
    slot = add(slot, inset)

    slot = rotate(slot, angle)
    slot = move(slot, x, y)
    return MString(slot)

# Render boundaries
cad.xmin = inchn(-18)
cad.xmax = inchn(18)
cad.ymin = inchn(-12)
cad.ymax = inchn(12)
#cad.mm_per_unit = 25.4 # inch units
cad.mm_per_unit = 1.0

# Overall variables
width = height = inch(18)
lip = 0
th = 4.0

# Shelf variables
shelf_width = inch(11.5)
shelf_height = inch(6)
shelf_offset = -height/6
wall_offset = th

# Slot variables
delta = width/2 - shelf_width/2
cham = 1.75
slot_depth = height/3

# Main panel
panel = rectangle(  -width/2 - lip,
                    width/2 + lip,
                    -height/2 - lip,
                    height/2 + lip - inchn(0.2))

# Shelf
shelf = rectangle(  -shelf_width/2, shelf_width/2,
                    shelf_offset-shelf_height/2, shelf_offset + shelf_height/2)
panel = subtract(panel, shelf)

# Slots
slots = []
slots.append(-shelf_width/2 - delta/2)
slots.append(-shelf_width/2 - wall_offset)
slots.append(shelf_width/2 + wall_offset)
slots.append(shelf_width/2 + delta/2)

for x in slots:
    # front panel slot
    cutout = wslot(x, height/2, th, slot_depth, 0, cham)
    panel = subtract(panel, cutout)

cad.function = panel