// ============================================
// Presence Sensor Wall-Mount Enclosure
// ESP32-S3 + OV5640 + LD2410C + AM312 + SHT41 + BH1750
// Board: 45 x 35 mm
// ============================================

// Dimensions (mm)
pcb_w = 45;          // PCB width
pcb_h = 35;          // PCB height
pcb_t = 1.6;         // PCB thickness

wall = 1.8;          // Wall thickness
tolerance = 0.3;     // Fit tolerance
bottom_gap = 3;      // Space below PCB for solder joints
top_gap = 12;        // Space above PCB for components + modules
lid_lip = 1.5;       // Lid overlap lip

// Derived
inner_w = pcb_w + tolerance * 2;
inner_h = pcb_h + tolerance * 2;
inner_d = bottom_gap + pcb_t + top_gap;
outer_w = inner_w + wall * 2;
outer_h = inner_h + wall * 2;
outer_d = inner_d + wall;  // Open top (lid covers)

// Screw post dimensions
post_d = 4.5;        // Post outer diameter
screw_d = 2.2;       // M2 screw hole
post_h = bottom_gap;  // Height to PCB level

// Component positions (from bottom-left of PCB)
cam_x = pcb_w / 2;          // Camera centered horizontally
cam_y = pcb_h - 5;          // Camera near top
cam_hole_w = 10;             // Camera lens window
cam_hole_h = 10;

pir_x = 12;                 // PIR left of center
pir_y = pcb_h - 20;
pir_hole_d = 10;             // AM312 dome diameter

light_x = 30;               // BH1750 right of center
light_y = pcb_h - 20;
light_hole_d = 4;            // Small window for light sensor

mmwave_x = pcb_w / 2;       // LD2410C centered
mmwave_y = 8;                // Near bottom
mmwave_slot_w = 8;           // Slot for radar signal
mmwave_slot_h = 36;

usbc_x = pcb_w / 2;         // USB-C centered bottom
usbc_w = 10;
usbc_h = 4;

vent_slot_w = 1.5;
vent_slot_h = 8;

// ============================================
// Main body
// ============================================
module body() {
    difference() {
        // Outer shell
        rounded_box(outer_w, outer_h, outer_d, 3);

        // Inner cavity
        translate([wall, wall, wall])
            rounded_box(inner_w, inner_h, inner_d + 1, 2);

        // Camera window (front face - top)
        translate([wall + tolerance + cam_x - cam_hole_w/2,
                   wall + tolerance + cam_y - cam_hole_h/2,
                   -1])
            rounded_box(cam_hole_w, cam_hole_h, wall + 2, 2);

        // PIR window (front face)
        translate([wall + tolerance + pir_x,
                   wall + tolerance + pir_y,
                   -1])
            cylinder(h=wall+2, d=pir_hole_d, $fn=32);

        // Light sensor window (front face)
        translate([wall + tolerance + light_x,
                   wall + tolerance + light_y,
                   -1])
            cylinder(h=wall+2, d=light_hole_d, $fn=32);

        // USB-C cutout (bottom edge)
        translate([wall + tolerance + usbc_x - usbc_w/2,
                   -1,
                   wall + bottom_gap - 1])
            cube([usbc_w, wall + 2, usbc_h + 2]);

        // Ventilation slots (sides - for SHT41 airflow)
        for (i = [0:3]) {
            // Left side
            translate([-1,
                       wall + 5 + i * (vent_slot_h + 2),
                       wall + bottom_gap + pcb_t + 2])
                cube([wall + 2, vent_slot_h, vent_slot_w]);
            // Right side
            translate([outer_w - wall - 1,
                       wall + 5 + i * (vent_slot_h + 2),
                       wall + bottom_gap + pcb_t + 2])
                cube([wall + 2, vent_slot_h, vent_slot_w]);
        }

        // mmWave radar slot (through back wall for better signal)
        translate([wall + tolerance + mmwave_x - mmwave_slot_w/2,
                   wall + tolerance + mmwave_y - mmwave_slot_h/2,
                   outer_d - wall - 0.5])
            rounded_box(mmwave_slot_w, mmwave_slot_h, wall + 1, 1);

        // Wall mount screw slots (keyhole on back)
        translate([outer_w/2, outer_h * 0.3, outer_d - wall - 1])
            wall_mount_keyhole();
        translate([outer_w/2, outer_h * 0.7, outer_d - wall - 1])
            wall_mount_keyhole();
    }

    // PCB support posts
    for (pos = [[wall + tolerance + 2.5, wall + tolerance + 2.5],
                [wall + tolerance + pcb_w - 2.5, wall + tolerance + 2.5],
                [wall + tolerance + 2.5, wall + tolerance + pcb_h - 2.5],
                [wall + tolerance + pcb_w - 2.5, wall + tolerance + pcb_h - 2.5]]) {
        translate([pos[0], pos[1], wall])
            difference() {
                cylinder(h=post_h, d=post_d, $fn=20);
                cylinder(h=post_h + 1, d=screw_d, $fn=20);
            }
    }
}

// ============================================
// Lid (snap-fit)
// ============================================
module lid() {
    difference() {
        union() {
            // Lid plate
            rounded_box(outer_w, outer_h, wall, 3);

            // Inner lip for alignment
            translate([wall - lid_lip/2, wall - lid_lip/2, wall])
                rounded_box(inner_w + lid_lip, inner_h + lid_lip, 2, 2);
        }

        // Status LED window (small hole)
        translate([wall + tolerance + 40, wall + tolerance + 25, -1])
            cylinder(h=wall+2, d=2, $fn=16);
    }
}

// ============================================
// Helper modules
// ============================================
module rounded_box(w, h, d, r) {
    hull() {
        translate([r, r, 0]) cylinder(h=d, r=r, $fn=20);
        translate([w-r, r, 0]) cylinder(h=d, r=r, $fn=20);
        translate([r, h-r, 0]) cylinder(h=d, r=r, $fn=20);
        translate([w-r, h-r, 0]) cylinder(h=d, r=r, $fn=20);
    }
}

module wall_mount_keyhole() {
    // Large hole (screw head)
    cylinder(h=wall+2, d=7, $fn=24);
    // Slot (slide down to lock)
    translate([0, -5, 0])
        hull() {
            cylinder(h=wall+2, d=4, $fn=24);
            translate([0, 5, 0]) cylinder(h=wall+2, d=4, $fn=24);
        }
}

// ============================================
// Render
// ============================================

// Body
body();

// Lid (offset for viewing - move to origin for printing)
translate([outer_w + 10, 0, 0])
    lid();