$fn = 64;

// --- Parameters ---
hook_width = 15;      // Width of the hook
base_height = 60;     // Total height of the wall plate
base_thickness = 9;   // Thickness of the wall plate

hook_out = 35;        // How far the hook extends from the wall
hook_up = 35;         // Height of the hook tip
hook_radius = 4.5;    // Rounding radius (determines hook thickness)

screw_dia = 4.5;      // Diameter of the mounting screw
screw_head_dia = 9.0; // Diameter of the screw head
screw_head_depth = 4; // Depth of the countersink

// The model is rotated and translated to lie flat on its side.
// This is the optimal orientation for 3D printing strength (layer lines run along the hook)
// and allows printing completely without supports.
translate([0, 0, hook_width / 2])
rotate([0, 90, 0]) {
    difference() {
        // Main Hook Body
        union() {
            // Base Plate
            hull() {
                translate([0, base_height - hook_radius, base_thickness - hook_radius])
                    rotate([0, 90, 0]) cylinder(r=hook_radius, h=hook_width, center=true);

                translate([0, hook_radius, base_thickness - hook_radius])
                    rotate([0, 90, 0]) cylinder(r=hook_radius, h=hook_width, center=true);

                // Ensure the back is filled before making it perfectly flat
                translate([0, base_height / 2, 0.5])
                    cube([hook_width, base_height, 1], center=true);
            }

            // Hook Arm (Lower sweeping segment)
            hull() {
                translate([0, hook_radius, base_thickness - hook_radius])
                    rotate([0, 90, 0]) cylinder(r=hook_radius, h=hook_width, center=true);

                translate([0, 15, 25])
                    rotate([0, 90, 0]) cylinder(r=hook_radius, h=hook_width, center=true);
            }

            // Hook Arm (Upper catching segment)
            hull() {
                translate([0, 15, 25])
                    rotate([0, 90, 0]) cylinder(r=hook_radius, h=hook_width, center=true);

                translate([0, hook_up, hook_out])
                    rotate([0, 90, 0]) cylinder(r=hook_radius, h=hook_width, center=true);
            }
        }

        // Flat back cutoff to ensure absolute flush mounting against the wall
        translate([0, base_height / 2, -5])
            cube([hook_width + 2, base_height + 20, 10], center=true);

        // Countersunk Screw Hole
        translate([0, base_height - 12, 0]) {
            // Screw shaft
            cylinder(d=screw_dia, h=base_thickness * 3, center=true);
            
            // Countersink
            translate([0, 0, base_thickness - screw_head_depth])
                cylinder(d1=screw_dia, d2=screw_head_dia, h=screw_head_depth + 0.1);
                
            // Clearance above the screw head
            translate([0, 0, base_thickness])
                cylinder(d=screw_head_dia, h=20);
        }
    }
}