$fn=64;

// --- Parameters ---
// Bin dimensions
bin_width = 200;
bin_depth = 150;
bin_height = 150;
wall_thickness = 3;
corner_radius = 8;

// Rail Mount dimensions (French cleat style for PetStation)
mount_width = 120;
mount_depth = 18;
lip_thickness = 6;
gap_height = 10;
hook_drop = 30;

// --- Modules ---
module rounded_rect(w, d, h, r) {
    hull() {
        translate([r, r, 0]) cylinder(r=r, h=h);
        translate([w-r, r, 0]) cylinder(r=r, h=h);
        translate([r, d-r, 0]) cylinder(r=r, h=h);
        translate([w-r, d-r, 0]) cylinder(r=r, h=h);
    }
}

// --- Main Assembly ---
union() {
    // Main Storage Bin
    difference() {
        // Outer shell
        rounded_rect(bin_width, bin_depth, bin_height, corner_radius);
        
        // Inner hollow
        translate([wall_thickness, wall_thickness, wall_thickness])
            rounded_rect(
                bin_width - 2*wall_thickness, 
                bin_depth - 2*wall_thickness, 
                bin_height + 1, // +1 ensures clean cut at the top
                max(0.1, corner_radius - wall_thickness)
            );
            
        // Front access scoop
        translate([bin_width/2, -30, bin_height + 60])
            rotate([0, 90, 0])
            cylinder(r=100, h=bin_width + 20, center=true);
    }

    // Back Wall Rail Mount (Printable without supports)
    translate([(bin_width - mount_width)/2, bin_depth - 0.1, bin_height - gap_height]) {
        // Base extension from the bin
        cube([mount_width, mount_depth, gap_height]);
        
        // Downward locking lip
        translate([0, mount_depth - lip_thickness, -hook_drop])
            cube([mount_width, lip_thickness, hook_drop]);
            
        // 45-degree support chamfer for 3D printability
        hull() {
            // Top edge against the base extension
            cube([mount_width, mount_depth - lip_thickness, 0.1]);
            // Bottom edge against the bin wall
            translate([0, 0, -(mount_depth - lip_thickness)])
                cube([mount_width, 0.1, 0.1]);
        }
    }
}