// Parametric Snap-in Cable Clip
// Designed for clean 3D printing and easy cable insertion

include <BOSL2/std.scad>

/* [Cable Parameters] */
// Nominal cable diameter (mm)
cable_diameter = 6.0;      // [2.0:0.5:20.0]
// Snap opening width at top (mm)
snap_opening = 5.5;        // [1.5:0.5:18.0]
// Clip wall thickness (mm)
wall_thickness = 1.6;      // [1.0:0.2:4.0]

/* [Base Parameters] */
// Base length along X (mm)
base_length = 20.0;        // [10.0:1.0:50.0]
// Base width / clip depth along Y (mm)
base_width = 12.0;         // [6.0:1.0:30.0]
// Base plate thickness (mm)
base_thickness = 2.0;      // [1.0:0.5:5.0]
// Base corner rounding radius (mm)
base_corner_radius = 2.5;  // [0.5:0.5:6.0]

/* [Lead-in & Reinforcement] */
// Flare angle of entry tabs (degrees)
flare_angle = 35;          // [15:5:60]
// Length of lead-in entry tabs (mm)
flare_length = 1.5;        // [0.5:0.5:4.0]
// Transition fillet radius at base (mm)
fillet_radius = 2.0;       // [0.5:0.5:5.0]

/* [Appearance] */
clip_color = "#1E88E5";    // Color picker
$fn = 64;

module cable_clip() {
    r_in = cable_diameter / 2;
    r_out = r_in + wall_thickness;
    
    // Safety check: ensure opening does not exceed diameter
    actual_opening = min(snap_opening, cable_diameter * 0.98);
    
    // Calculate angle corresponding to half opening
    // sin(half_angle) = (opening / 2) / r_in
    sin_val = min(0.98, (actual_opening / 2) / r_in);
    half_angle_rad = asin(sin_val);
    half_angle_deg = half_angle_rad; // in degrees in OpenSCAD
    
    // Cable center height above base
    cable_center_z = base_thickness + r_in + 0.4;
    
    color(clip_color) {
        // 1. Base Plate with rounded corners
        cuboid([base_length, base_width, base_thickness], 
               rounding=base_corner_radius, 
               edges="Z", 
               anchor=BOTTOM) 
        {
            // Attach C-clip on top of base
            position(TOP) {
                // 2. C-shaped arm and base transition
                rotate([90, 0, 0])
                linear_extrude(height=base_width, center=true, convexity=4) {
                    clip_2d_profile(r_in, r_out, half_angle_deg, cable_center_z - base_thickness);
                }
            }
        }
    }
}

module clip_2d_profile(r_in, r_out, half_angle, center_h) {
    // Center of the cable circle
    cx = 0;
    cy = center_h;
    
    // Tip coordinates at inner and outer arc
    // Angle measured from top (+Y axis): +/- half_angle
    tip_angle = half_angle;
    
    // Generate 2D C-shape with flared entry tabs and base fillets
    difference() {
        union() {
            // Main outer circular body
            translate([cx, cy])
                circle(r=r_out);
            
            // Base support gussets / fillet blending to flat base
            polygon(points=[
                [-r_out, 0],
                [r_out, 0],
                [r_out + fillet_radius, 0],
                [r_out, cy],
                [-r_out, cy],
                [-r_out - fillet_radius, 0]
            ]);
            
            // Curved side fillets blending clip to base
            translate([r_out + fillet_radius, 0])
                difference() {
                    square([fillet_radius * 1.5, fillet_radius * 1.5], center=false);
                    translate([0, fillet_radius])
                        circle(r=fillet_radius);
                }
            translate([-r_out - fillet_radius - fillet_radius * 1.5, 0])
                difference() {
                    translate([fillet_radius * 1.5, 0])
                        square([fillet_radius * 1.5, fillet_radius * 1.5], center=false);
                    translate([fillet_radius * 1.5, fillet_radius])
                        circle(r=fillet_radius);
                }

            // Lead-in entry tabs (flared lips for easy snap insertion)
            for (side = [-1, 1]) {
                // Tip start point on the outer wall
                x_tip = side * (r_out - 0.2) * sin(tip_angle);
                y_tip = cy + (r_out - 0.2) * cos(tip_angle);
                
                translate([x_tip, y_tip])
                rotate([0, 0, -side * (tip_angle + flare_angle)])
                hull() {
                    circle(r=wall_thickness / 2);
                    translate([0, flare_length])
                        circle(r=wall_thickness / 2.5);
                }
            }
        }
        
        // Inner cable cutout
        translate([cx, cy])
            circle(r=r_in);
        
        // Top snap opening sector cutout
        polygon(points=[
            [cx, cy],
            [cx + 3 * r_out * sin(tip_angle), cy + 3 * r_out * cos(tip_angle)],
            [cx + 3 * r_out * sin(tip_angle), cy + 4 * r_out],
            [cx - 3 * r_out * sin(tip_angle), cy + 4 * r_out],
            [cx - 3 * r_out * sin(tip_angle), cy + 3 * r_out * cos(tip_angle)]
        ]);
    }
    
    // Rounded tip ends for soft, smooth snap
    for (side = [-1, 1]) {
        x_inner = side * r_in * sin(tip_angle);
        y_inner = cy + r_in * cos(tip_angle);
        x_outer = side * r_out * sin(tip_angle);
        y_outer = cy + r_out * cos(tip_angle);
        
        // Soft bead at the inner edge
        hull() {
            translate([(x_inner + x_outer)/2, (y_inner + y_outer)/2])
                circle(r=wall_thickness / 2);
        }
    }
}

// Render the assembly
cable_clip();