$fn=64;

// --- Parametric Dimensions ---

// Trellis Body
trellis_width = 120;
trellis_height = 180;
trellis_thickness = 4;
frame_width = 6;

// Diamond Grid
grid_spacing = 22;
grid_thickness = 2.5;

// Pot Rim Clips
pot_rim_thickness = 4.5; // Adjust based on your pot's rim width
clip_depth = 20;
clip_thickness = 4;      // Wall thickness of the clips
clip_spacing = 70;       // Distance between the two clips

// --- Modules ---

// Generates the main arch shape for the trellis
module arch_2d(shrink=0) {
    offset(r=-shrink)
    hull() {
        // Top rounded arch
        translate([0, trellis_height - trellis_width/2]) 
            circle(d=trellis_width);
        // Bottom left corner
        translate([-trellis_width/2 + 5, 5]) 
            circle(r=5);
        // Bottom right corner
        translate([trellis_width/2 - 5, 5]) 
            circle(r=5);
    }
}

// Generates a single downward-facing clip
module clip() {
    clip_w = pot_rim_thickness + (clip_thickness * 2);
    
    difference() {
        // Outer clip body
        translate([0, -clip_depth/2 + 1]) 
            square([clip_w, clip_depth + 2], center=true);
        
        // Inner slot for the pot rim
        translate([0, -clip_depth/2 - 2]) 
            square([pot_rim_thickness, clip_depth], center=true);
        
        // Flared opening to easily slide onto the rim
        translate([0, -clip_depth]) 
            polygon([
                [-pot_rim_thickness/2, 0.1],
                [pot_rim_thickness/2, 0.1],
                [pot_rim_thickness/2 + clip_thickness, -clip_thickness],
                [-pot_rim_thickness/2 - clip_thickness, -clip_thickness]
            ]);
    }
}

// --- Main Assembly ---

linear_extrude(trellis_thickness) {
    union() {
        // 1. Outer Frame
        difference() {
            arch_2d(0);
            arch_2d(frame_width);
        }
        
        // 2. Diamond Lattice Grid
        intersection() {
            // Embed grid slightly into the frame for a strong, clean union
            arch_2d(frame_width/2);
            union() {
                for(i = [-trellis_width*1.5 : grid_spacing : trellis_width*1.5]) {
                    translate([i, 0]) rotate(45) 
                        square([grid_thickness, trellis_height*3], center=true);
                    translate([i, 0]) rotate(-45) 
                        square([grid_thickness, trellis_height*3], center=true);
                }
            }
        }
        
        // 3. Solid Base Crossbar
        translate([0, frame_width/2]) 
            square([trellis_width, frame_width], center=true);
        
        // 4. Pot Mounting Clips
        translate([-clip_spacing/2, 0]) clip();
        translate([clip_spacing/2, 0]) clip();
    }
}