$fn = 64;

// --- Parametric Dimensions ---
holder_width = 120;     // Total width of the holder
body_depth = 86;        // Depth of the slotted section
holder_height = 40;     // Height of the slotted section
corner_radius = 8;      // Radius for the front corners
slot_depth = 30;        // Depth of the slots (leaves a 10mm solid base)
wall_thickness = 8;     // Thickness of the backplate
backplate_height = 60;  // Total height of the wall mount backplate

// Slot positions and widths [y_offset, slot_width]
// y_offset is relative to the front of the backplate
slots = [
    [8,  2],   // Thin metal ruler
    [18, 3],   // Standard ruler
    [29, 4],   // Thick ruler
    [41, 5],   // Straight edge
    [54, 6],   // Heavy straight edge
    [68, 10]   // T-square blade
];

// --- Modules ---

// Generic rail cleat (compatible with most 45-deg wall rail systems like ArtArsenal)
module rail_cleat() {
    // Extrude the cleat profile along the X axis
    // rotate([90, 0, 90]) maps (Xp, Yp, Zp) to (Zp, Xp, Yp)
    rotate([90, 0, 90])
    linear_extrude(height=holder_width) {
        polygon([
            [wall_thickness, 0],
            [wall_thickness, backplate_height],
            [-8, backplate_height],           // Hook extends 8mm back
            [-8, backplate_height - 8],       // Hook straight down 8mm
            [0, backplate_height - 16],       // 45 deg angle back to wall
            [0, 0]                            // Flat against wall down to 0
        ]);
    }
}

// Main solid body before slot cuts
module body_base() {
    hull() {
        // Overlap with backplate by 1mm to ensure manifold geometry
        translate([0, wall_thickness - 1, 0])
            cube([holder_width, 1, holder_height]);

        // Front rounded corners
        translate([corner_radius, wall_thickness + body_depth - corner_radius, 0])
            cylinder(r=corner_radius, h=holder_height);
        translate([holder_width - corner_radius, wall_thickness + body_depth - corner_radius, 0])
            cylinder(r=corner_radius, h=holder_height);
    }
}

// Body with vertical slots removed
module slotted_holder() {
    difference() {
        body_base();

        // Cut out the slots
        for (s = slots) {
            y_offset = s[0];
            slot_w = s[1];
            
            // Oversize cuts slightly in X and Z to ensure clean subtraction
            translate([-5, wall_thickness + y_offset, holder_height - slot_depth])
                cube([holder_width + 10, slot_w, slot_depth + 5]);
        }
    }
}

// --- Main Assembly ---
union() {
    rail_cleat();
    slotted_holder();
}