$fn = 64;

// --- Parameters ---
hex_outer_radius = 20;    // Outer radius of a single hexagon (center to point)
wall_thickness = 1.5;     // Thickness of the shared walls and outer walls
floor_thickness = 1.5;    // Thickness of the bottom floor
unit_height = 25;         // Total height of the bin (1 unit)

// --- Calculated Values ---
// Apothem is the distance from the center to the flat edge
apothem_out = hex_outer_radius * cos(30);

// Distance between centers to share exactly 'wall_thickness'
center_dist = 2 * apothem_out - wall_thickness;

// Inner radius to maintain consistent wall thickness
hex_inner_radius = hex_outer_radius - (wall_thickness / cos(30));

// Centers for the 7 hexagons (1 center, 6 surrounding at 60-degree intervals)
centers = [
    [0, 0],
    [center_dist * cos(0),   center_dist * sin(0)],
    [center_dist * cos(60),  center_dist * sin(60)],
    [center_dist * cos(120), center_dist * sin(120)],
    [center_dist * cos(180), center_dist * sin(180)],
    [center_dist * cos(240), center_dist * sin(240)],
    [center_dist * cos(300), center_dist * sin(300)]
];

// --- Geometry ---
difference() {
    // Outer solid body
    union() {
        for (c = centers) {
            translate([c[0], c[1], 0])
                // Rotate 30 degrees so flat edges face the adjacent centers
                rotate([0, 0, 30])
                cylinder(h=unit_height, r=hex_outer_radius, $fn=6);
        }
    }
    
    // Inner hollow cavities
    for (c = centers) {
        translate([c[0], c[1], floor_thickness])
            rotate([0, 0, 30])
            // Height + 1 ensures clean manifold subtraction through the top
            cylinder(h=unit_height + 1, r=hex_inner_radius, $fn=6);
    }
}