# IMU Pointer Enclosure — FreeCAD Macro v5
# ==========================================
# Lid drops INSIDE the base.
# Base has a shelf step cut 1.5mm into the inner walls,
# LID_STEP mm from the top. Lid rests on that shelf, flush with base top.
# USB-C notch on front edge of lid keeps port accessible.
#
# Layout (top view, front = left):
#   [USB-C][ XIAO on posts ]<-wires->[ AAA holder ][ grip ]
# ==========================================

import FreeCAD as App
import FreeCADGui as Gui
import Part
import Mesh
import os
from FreeCAD import Base

doc = App.newDocument("IMU_Pointer_v5")

# ---- PARAMETERS ------------------------------------------------------------

L    = 115.0
W    =  34.0
H    =  28.0
WALL =   2.5
CR   =   3.0   # corner fillet radius

TOL  =   0.25  # fit clearance — lid is this much smaller than the shelf opening

# Shelf: step cut into inside of base walls near the top
# Lid sits on this shelf, flush with the base rim
SHELF_DEPTH =  1.5   # how far shelf cuts inward from the inner wall face
SHELF_H     =  2.0   # how tall the shelf step is (from top of base downward)
                     # lid height = SHELF_H so it sits exactly flush

LID_H = SHELF_H      # lid is exactly as tall as the shelf recess

# XIAO board (front of device)
BRD_L  = 21.0
BRD_W  = 18.0
BRD_X  = WALL + 4.0
BRD_Y  = (W - BRD_W) / 2
BRD_Z  = WALL + 4.5

# AAA battery holder
BAT_L  = 50.0
BAT_W  = 12.0
BAT_H  = 12.0
BAT_X  = BRD_X + BRD_L + 6.0
BAT_Y  = (W - BAT_W) / 2

# L-post mount
POST_OD = 3.5
POST_ID = 1.6
POST_H  = BRD_Z
L_ARM   = 2.2
L_THICK = 1.2

# USB-C cutout on front face
USBC_W  =  9.5
USBC_H  =  3.5
USBC_Z  =  BRD_Z + 0.8

MACRO_DIR = os.path.dirname(os.path.abspath(__file__))

# ---- HELPERS ---------------------------------------------------------------

def rbox(lx, ly, lz, ox=0, oy=0, oz=0, r=CR):
    b = Part.makeBox(lx, ly, lz, Base.Vector(ox, oy, oz))
    try:
        vert = [e for e in b.Edges
                if abs(e.Vertexes[0].Z - e.Vertexes[1].Z) > lz * 0.9]
        if vert:
            b = b.makeFillet(r, vert)
    except Exception:
        pass
    return b

def box(lx, ly, lz, ox=0, oy=0, oz=0):
    return Part.makeBox(lx, ly, lz, Base.Vector(ox, oy, oz))

def cyl(r, h, ox=0, oy=0, oz=0):
    return Part.makeCylinder(r, h, Base.Vector(ox, oy, oz))

def export_stl(shape, name):
    path = os.path.join(MACRO_DIR, name)
    tess = shape.tessellate(0.06)
    m = Mesh.Mesh(list(zip(tess[0], tess[1])))
    m.write(path)
    print(f"  Saved: {path}")

# ====================================================================
# BASE
# ====================================================================

base = rbox(L, W, H)
# Main inner cavity — full height minus floor
base = base.cut(box(L - WALL*2, W - WALL*2, H - WALL, WALL, WALL, WALL))

# Shelf recess: widen the top SHELF_H of the inner cavity by SHELF_DEPTH
# This creates the step the lid rests on
shelf_cut = box(L - WALL*2 + SHELF_DEPTH*2,
                W - WALL*2 + SHELF_DEPTH*2,
                SHELF_H + 0.1,
                WALL - SHELF_DEPTH,
                WALL - SHELF_DEPTH,
                H - SHELF_H)
base = base.cut(shelf_cut)

# USB-C slot on front face (X=0)
base = base.cut(box(WALL*3, USBC_W, USBC_H,
                    -WALL, W/2 - USBC_W/2, USBC_Z))

# ---- L-shaped mounting posts ----
brd_cx = BRD_X + BRD_L / 2
brd_cy = BRD_Y + BRD_W / 2
post_corners = [
    (BRD_X + 2.0,         BRD_Y + 2.0),
    (BRD_X + BRD_L - 2.0, BRD_Y + 2.0),
    (BRD_X + 2.0,         BRD_Y + BRD_W - 2.0),
    (BRD_X + BRD_L - 2.0, BRD_Y + BRD_W - 2.0),
]
for (px, py) in post_corners:
    post = cyl(POST_OD/2, POST_H, px, py, WALL)
    post = post.cut(cyl(POST_ID/2, POST_H + 1.0, px, py, WALL - 0.5))
    dx = brd_cx - px;  dy = brd_cy - py
    mag = (dx**2 + dy**2)**0.5;  dx /= mag;  dy /= mag
    perp_x = -dy;  perp_y = dx;  hw = L_THICK / 2
    z0 = WALL + POST_H - L_THICK;  z1 = WALL + POST_H
    p0 = Base.Vector(px - perp_x*hw, py - perp_y*hw, z0)
    p1 = Base.Vector(px + perp_x*hw, py + perp_y*hw, z0)
    p2 = Base.Vector(px + perp_x*hw, py + perp_y*hw, z1)
    p3 = Base.Vector(px - perp_x*hw, py - perp_y*hw, z1)
    arm = Part.Face(Part.Wire([
        Part.makeLine(p0,p1), Part.makeLine(p1,p2),
        Part.makeLine(p2,p3), Part.makeLine(p3,p0)
    ])).extrude(Base.Vector(dx*L_ARM, dy*L_ARM, 0))
    base = base.fuse(post.fuse(arm))

# ---- Battery cradle ----
base = base.cut(box(BAT_L, BAT_W, 3.0, BAT_X, BAT_Y, WALL))
base = base.fuse(box(2.0, BAT_W+3.0, BAT_H*0.55, BAT_X-2.0,   BAT_Y-1.5, WALL))
base = base.fuse(box(2.0, BAT_W+3.0, BAT_H*0.55, BAT_X+BAT_L, BAT_Y-1.5, WALL))

print("[1/2] Base complete.")

# ====================================================================
# LID  — sized to drop inside the shelf opening, built at Z=0
# ====================================================================
# Lid outer dimensions match the shelf recess minus tolerance
LID_L = L - WALL*2 + SHELF_DEPTH*2 - TOL*2
LID_W = W - WALL*2 + SHELF_DEPTH*2 - TOL*2

lid = rbox(LID_L, LID_W, LID_H,
           WALL - SHELF_DEPTH + TOL,
           WALL - SHELF_DEPTH + TOL,
           0, r=1.5)

# USB-C notch on front edge (X=0 face of lid) so port stays accessible
# The notch is a slot cut from the front edge, aligned with USB-C position
notch_y = W/2 - USBC_W/2 - (WALL - SHELF_DEPTH + TOL)  # relative to lid origin
lid = lid.cut(box(WALL*2, USBC_W, USBC_H + 0.5,
                  -(WALL - SHELF_DEPTH + TOL),   # punch through front face
                  W/2 - USBC_W/2,
                  0))

print("[2/2] Lid complete.")

# Export STLs at Z=0 BEFORE any translation
print("\nExporting STLs...")
export_stl(base, "pointer_base.stl")
export_stl(lid,  "pointer_lid.stl")

# Translate lid up to assembled position for FreeCAD viewport only
lid.translate(Base.Vector(0, 0, H - LID_H))

# ====================================================================
# DOCUMENT
# ====================================================================
base_obj = doc.addObject("Part::Feature", "Pointer_Base")
base_obj.Shape = base
base_obj.ViewObject.ShapeColor = (0.12, 0.12, 0.14)

lid_obj = doc.addObject("Part::Feature", "Pointer_Lid")
lid_obj.Shape = lid
lid_obj.ViewObject.ShapeColor  = (0.28, 0.28, 0.34)
lid_obj.ViewObject.Transparency = 25

doc.recompute()
Gui.activeDocument().activeView().viewIsometric()
Gui.SendMsgToActiveView("ViewFit")

print()
print("=" * 62)
print("IMU Pointer v5 — lid drops INSIDE base")
print(f"  Outer         : {L:.0f} x {W:.0f} x {H:.0f} mm")
print(f"  Shelf step    : {SHELF_DEPTH:.1f} mm inward, {SHELF_H:.1f} mm tall")
print(f"  Lid           : {LID_L:.1f} x {LID_W:.1f} x {LID_H:.1f} mm")
print(f"  Tolerance     : {TOL:.2f} mm")
print()
print("Assembly:")
print("  Drop lid flat-side-up into the top opening.")
print("  It rests on the shelf, sitting flush with the base rim.")
print("  USB-C notch on front edge keeps port fully accessible.")
print("  To remove: push up from the USB-C hole or pry with fingernail.")
print()
print("Print orientation:")
print("  Base: flat bottom down, no supports")
print("  Lid : either face down, it's a flat plate — no supports")
print("=" * 62)