$fn = 64;

// --- Parameters ---
tower_height = 120;
base_radius = 40;
top_radius = 32;
wall_thickness = 4;

// Cable routing dimensions
cable_hole_width = 22;
cable_hole_height = 25; // Height of the straight section before the arch

// Castle details
crenellation_height = 12;
crenellation_count = 8;
crenellation_gap = 14;

// --- Helper Module ---
module arch_cutout(width, height, depth) {
    translate([-width/2, 0, -1])
        cube([width, depth, height + 1]);
    translate([0, 0, height])
        rotate([-90, 0, 0])
        cylinder(h = depth, d = width);
}

// --- Main Model ---
difference() {
    // 1. Solid Outer Shell
    union() {
        // Base flare for stability
        cylinder(h = 10, r1 = base_radius + 8, r2 = base_radius);
        
        // Main tower body
        cylinder(h = tower_height, r1 = base_radius, r2 = top_radius);
        
        // Top flare (corbel)
        translate([0, 0, tower_height - 10])
            cylinder(h = 10, r1 = top_radius, r2 = top_radius + 6);
            
        // Top crenellation ring
        translate([0, 0, tower_height])
            cylinder(h = crenellation_height, r = top_radius + 6);
    }

    // 2. Hollow Interior for Cables
    translate([0, 0, -1])
        cylinder(
            h = tower_height + crenellation_height + 2,
            r1 = base_radius - wall_thickness,
            r2 = top_radius - wall_thickness
        );

    // 3. Bottom Cable Entrance (Front)
    rotate([0, 0, 180])
        arch_cutout(cable_hole_width, cable_hole_height, base_radius + 20);

    // 4. Top Cable Exit (Back)
    translate([0, 0, tower_height - cable_hole_height - 20])
        arch_cutout(cable_hole_width, cable_hole_height, base_radius + 20);

    // 5. Crenellation Gaps (Battlements)
    for (i = [0 : crenellation_count - 1]) {
        rotate([0, 0, i * (360 / crenellation_count)])
            translate([-crenellation_gap/2, top_radius - 5, tower_height - 1])
            cube([crenellation_gap, 20, crenellation_height + 2]);
    }
}