// Raspberry Pi Pico Two-Piece Enclosure
// Parametric OpenSCAD Model

/* [Board Dimensions] */
board_length = 51.0;            // [40:0.5:70]
board_width = 21.0;             // [15:0.5:35]
board_thickness = 1.0;          // [0.5:0.1:3]
hole_inset_x = 2.0;             // [1:0.1:5]
hole_inset_y = 4.8;             // [1:0.1:8]
hole_diameter = 2.1;            // [1.5:0.1:3.5]

/* [Enclosure Settings] */
wall_thickness = 2.0;           // [1.2:0.1:4.0]
board_clearance = 1.0;          // [0.2:0.1:3.0]
post_height = 3.0;              // [1.0:0.5:8.0]
post_diameter = 4.0;            // [2.5:0.1:6.0]
pin_diameter = 1.9;             // [1.2:0.1:2.5]
pin_height = 1.8;               // [0.5:0.1:3.0]
inner_depth = 9.0;              // [6.0:0.5:20.0]
corner_radius = 2.5;            // [0.0:0.5:6.0]

/* [Cutout Settings] */
usb_width = 8.0;                // [5.0:0.5:15.0]
usb_height = 3.5;               // [2.0:0.5:8.0]

/* [Lid Settings] */
lid_thickness = 2.0;            // [1.0:0.5:5.0]
lip_height = 2.5;               // [1.0:0.5:6.0]
lip_thickness = 1.0;            // [0.6:0.1:2.0]
fit_tolerance = 0.15;           // [0.0:0.05:0.5]
part_spacing = 15.0;            // [5:1:40]

/* [Colors] */
base_color = "RoyalBlue";
lid_color = "LightSteelBlue";

/* [Display] */
$fn = 48;

// Derived Dimensions
inner_x = board_length + 2 * board_clearance;
inner_y = board_width + 2 * board_clearance;
outer_x = inner_x + 2 * wall_thickness;
outer_y = inner_y + 2 * wall_thickness;
total_height_base = inner_depth + wall_thickness;

// 2D Rounded Rectangle Helper
module rounded_rect(w, h, r) {
    if (r > 0) {
        hull() {
            translate([r, r]) circle(r=r);
            translate([w - r, r]) circle(r=r);
            translate([w - r, h - r]) circle(r=r);
            translate([r, h - r]) circle(r=r);
        }
    } else {
        square([w, h]);
    }
}

// Base Enclosure
module pico_base() {
    difference() {
        // Outer Shell
        linear_extrude(height=total_height_base)
            rounded_rect(outer_x, outer_y, corner_radius);

        // Inner Pocket
        translate([wall_thickness, wall_thickness, wall_thickness])
            linear_extrude(height=inner_depth + 1)
                rounded_rect(inner_x, inner_y, max(0.1, corner_radius - wall_thickness));

        // Micro-USB Cutout (centered on X=0 end at board level)
        translate([-1, outer_y / 2 - usb_width / 2, wall_thickness + post_height])
            cube([wall_thickness + 2, usb_width, usb_height]);
    }

    // Four Mounting Standoffs with Pins
    for (ix = [hole_inset_x, board_length - hole_inset_x]) {
        for (iy = [hole_inset_y, board_width - hole_inset_y]) {
            px = wall_thickness + board_clearance + ix;
            py = wall_thickness + board_clearance + iy;

            translate([px, py, wall_thickness]) {
                // Post boss
                cylinder(h=post_height, d=post_diameter);
                // Alignment pin through mounting hole
                translate([0, 0, post_height])
                    cylinder(h=pin_height, d=pin_diameter);
            }
        }
    }
}

// Snap/Friction-Fit Lid
module pico_lid() {
    union() {
        // Main Lid Plate
        linear_extrude(height=lid_thickness)
            rounded_rect(outer_x, outer_y, corner_radius);

        // Friction-fit lip extending into base cavity
        lip_outer_w = inner_x - 2 * fit_tolerance;
        lip_outer_h = inner_y - 2 * fit_tolerance;
        lip_corner_r = max(0.1, corner_radius - wall_thickness - fit_tolerance);

        translate([wall_thickness + fit_tolerance, wall_thickness + fit_tolerance, lid_thickness]) {
            difference() {
                // Outer lip boundary
                linear_extrude(height=lip_height)
                    rounded_rect(lip_outer_w, lip_outer_h, lip_corner_r);

                // Hollow center of lip
                translate([lip_thickness, lip_thickness, -0.5])
                    linear_extrude(height=lip_height + 1)
                        rounded_rect(
                            lip_outer_w - 2 * lip_thickness,
                            lip_outer_h - 2 * lip_thickness,
                            max(0.1, lip_corner_r - lip_thickness)
                        );
                
                // Cutout on lip for micro-USB clearance when closed
                translate([-1, (lip_outer_h - usb_width) / 2, -0.5])
                    cube([lip_thickness + 2, usb_width, lip_height + 1]);
            }
        }
        
        // Subtle finger pry notch on lid edge
        translate([outer_x - 1.5, outer_y / 2 - 4, lid_thickness - 0.8])
            cube([2, 8, 1]);
    }
}

// Scene layout: Base and Lid side by side
color(base_color)
    pico_base();

color(lid_color)
    translate([outer_x + part_spacing, 0, 0])
        pico_lid();