$fn = 64;

// --- Parametric Dimensions (in mm) ---
trellis_width = 140;      // Overall width of the trellis
trellis_height = 160;     // Height of the rectangular section (arch adds to this)
grid_spacing = 28;        // Distance between grid lines
bar_thickness = 4;        // Z-height/thickness (ideal for fast flat printing)
bar_width = 6;            // Width of the individual structural bars
stake_length = 80;        // Length of the ground/pot insertion stakes

// --- Main Assembly ---
union() {
    outer_frame();
    
    // Inner grid constrained exactly to the trellis boundary
    intersection() {
        grid();
        trellis_boundary();
    }
    
    stakes();
}

// --- Modules ---

// Solid shape representing the entire boundary of the trellis (used for intersection)
module trellis_boundary() {
    union() {
        translate([-trellis_width/2, 0, 0]) 
            cube([trellis_width, trellis_height, bar_thickness]);
        translate([0, trellis_height, 0]) 
            cylinder(h=bar_thickness, d=trellis_width);
    }
}

// The thick outer border of the trellis
module outer_frame() {
    union() {
        // Left vertical side
        translate([-trellis_width/2, 0, 0]) 
            cube([bar_width, trellis_height, bar_thickness]);
        
        // Right vertical side
        translate([trellis_width/2 - bar_width, 0, 0]) 
            cube([bar_width, trellis_height, bar_thickness]);
        
        // Bottom horizontal base
        translate([-trellis_width/2, 0, 0]) 
            cube([trellis_width, bar_width, bar_thickness]);

        // Top Arch
        translate([0, trellis_height, 0])
            difference() {
                cylinder(h=bar_thickness, d=trellis_width);
                
                // Hollow out the center of the arch
                translate([0, 0, -1]) 
                    cylinder(h=bar_thickness + 2, d=trellis_width - 2*bar_width);
                
                // Remove the bottom half of the arch to make it a semi-circle
                translate([-trellis_width/2 - 1, -trellis_width/2 - 1, -1])
                    cube([trellis_width + 2, trellis_width/2 + 1, bar_thickness + 2]);
            }
    }
}

// The internal intersecting lattice
module grid() {
    union() {
        // Vertical bars
        for(x = [-trellis_width/2 + grid_spacing : grid_spacing : trellis_width/2 - 1]) {
            translate([x - bar_width/2, 0, 0])
                cube([bar_width, trellis_height + trellis_width/2, bar_thickness]);
        }
        // Horizontal bars
        for(y = [grid_spacing : grid_spacing : trellis_height + trellis_width/2 - 1]) {
            translate([-trellis_width/2, y - bar_width/2, 0])
                cube([trellis_width, bar_width, bar_thickness]);
        }
    }
}

// Ground insertion stakes at the bottom
module stakes() {
    union() {
        // Left stake body
        translate([-trellis_width/2, -stake_length, 0])
            cube([bar_width, stake_length, bar_thickness]);
            
        // Left stake tip
        translate([-trellis_width/2, -stake_length - bar_width*1.5, 0])
            linear_extrude(height=bar_thickness)
            polygon([[0, bar_width*1.5], [bar_width, bar_width*1.5], [bar_width/2, 0]]);

        // Right stake body
        translate([trellis_width/2 - bar_width, -stake_length, 0])
            cube([bar_width, stake_length, bar_thickness]);
            
        // Right stake tip
        translate([trellis_width/2 - bar_width, -stake_length - bar_width*1.5, 0])
            linear_extrude(height=bar_thickness)
            polygon([[0, bar_width*1.5], [bar_width, bar_width*1.5], [bar_width/2, 0]]);
    }
}