$fn=64;

// --- PARAMETERS ---
length = 200;           // Total length of the raceway
base_width = 30;        // Outer width of the base
base_height = 15;       // Height of the base
wall_thickness = 1.6;   // Wall thickness (optimal for 0.4mm nozzle)
snap_radius = 0.8;      // Radius of the snap fit ridges
clearance = 0.2;        // Tolerance for the snap fit

// Derived Lid Parameters
lid_inner_width = base_width + (2 * snap_radius) + (2 * clearance);
lid_outer_width = lid_inner_width + (2 * wall_thickness);
lid_cavity_depth = 4.5; 
lid_height = wall_thickness + lid_cavity_depth;

// --- RENDER ---
// Place base and lid side-by-side for easy 3D printing
raceway_base();

translate([base_width + 15, 0, 0])
    raceway_lid();

// --- MODULES ---
module raceway_base() {
    union() {
        difference() {
            // Main channel body
            cube([base_width, length, base_height]);
            
            // Inner hollow
            translate([wall_thickness, -1, wall_thickness])
                cube([base_width - (2 * wall_thickness), length + 2, base_height]);
            
            // Mounting screw holes with countersink
            for (y = [30, length/2, length-30]) {
                // Screw shaft
                translate([base_width/2, y, -0.1])
                    cylinder(h=wall_thickness + 0.2, d=4.5);
                // Countersink
                translate([base_width/2, y, wall_thickness - 1.2])
                    cylinder(h=1.3, d1=4.5, d2=8);
            }
        }
        
        // Left snap ridge (outward facing)
        translate([0, 0, base_height - 2.5])
            rotate([-90, 0, 0])
            cylinder(h=length, r=snap_radius);
            
        // Right snap ridge (outward facing)
        translate([base_width, 0, base_height - 2.5])
            rotate([-90, 0, 0])
            cylinder(h=length, r=snap_radius);
    }
}

module raceway_lid() {
    // Printed upside down for support-free printing
    union() {
        difference() {
            // Main lid body
            cube([lid_outer_width, length, lid_height]);
            
            // Inner cavity
            translate([wall_thickness, -1, wall_thickness])
                cube([lid_inner_width, length + 2, lid_cavity_depth + 1]);
        }
        
        // Left snap ridge (inward facing)
        translate([wall_thickness, 0, wall_thickness + 3.5])
            rotate([-90, 0, 0])
            cylinder(h=length, r=snap_radius);
            
        // Right snap ridge (inward facing)
        translate([wall_thickness + lid_inner_width, 0, wall_thickness + 3.5])
            rotate([-90, 0, 0])
            cylinder(h=length, r=snap_radius);
    }
}