$fn = 64;

// --- Parameters ---
pot_inner_diameter = 100; // Inner diameter of the pot rim
rim_thickness = 5;        // Thickness of the pot rim
clip_depth = 12;          // How far the clip extends down into the pot
fence_height = 35;        // Height of the picket fence
fence_thickness = 2;      // Base thickness of the fence components
num_pickets = 36;         // Total number of pickets around the rim

// --- Derived Variables ---
r_inner = pot_inner_diameter / 2;
t = fence_thickness;
r_outer = r_inner + rim_thickness + t;

// --- Modules ---

// The inverted U-channel that clips onto the pot rim
module pot_clip() {
    rotate_extrude() {
        // Inner lip (inside the pot)
        translate([r_inner, -clip_depth, 0]) 
            square([t, clip_depth + t]);
        
        // Top resting surface
        translate([r_inner, 0, 0]) 
            square([rim_thickness + t*2, t]);
        
        // Outer lip (base for the fence)
        translate([r_outer, -clip_depth, 0]) 
            square([t, clip_depth + t]);
    }
}

// Horizontal rails connecting the pickets
module rail(z_offset) {
    translate([0, 0, z_offset])
    rotate_extrude() {
        // Overlap by 0.5mm for manifold geometry
        translate([r_outer + t - 0.5, 0, 0])
            square([t, t]);
    }
}

// Individual picket or post
module picket(is_post) {
    w = is_post ? 6 : 4;
    h = is_post ? fence_height + 6 : fence_height;
    p_thick = t + 1; // Pickets protrude slightly past rails for texture
    
    // Base rectangular shaft
    translate([-w/2, -0.5, 0]) 
        cube([w, p_thick, h - w/2]);
        
    // Decorative top (sphere for posts, rounded for pickets)
    if (is_post) {
        translate([0, p_thick/2 - 0.5, h - w/2]) 
            sphere(d=w + 2);
    } else {
        translate([0, p_thick/2 - 0.5, h - w/2]) 
            rotate([90, 0, 0]) 
            cylinder(h=p_thick, d=w, center=true);
    }
}

// --- Assembly ---
union() {
    pot_clip();
    
    // Lower and upper rails
    rail(8);
    rail(fence_height - 12);
    
    // Radial placement of pickets
    for (i = [0 : num_pickets - 1]) {
        angle = i * (360 / num_pickets);
        is_post = i % 4 == 0; // Every 4th picket is a thicker post
        
        rotate([0, 0, angle])
            translate([r_outer + t, 0, 0])
            picket(is_post);
    }
}