$fn = 64;

// --- PARAMETERS ---
roll_width = 120;       // Width of the paper roll
roll_max_dia = 100;     // Maximum diameter of the paper roll
core_dia = 20;          // Diameter of the roll's inner core
wall_thick = 5;         // Thickness of the walls

// Calculated dimensions
X_size = roll_width + 2 * wall_thick;
Y_size = roll_max_dia + wall_thick + 10;
Z_size = roll_max_dia + 30;

spindle_y = wall_thick + roll_max_dia/2 + 5;
spindle_z = Z_size - roll_max_dia/2 - 10;

// --- MAIN ASSEMBLY ---
// Printed in an orientation that requires zero supports
dispenser();
spindle();

module dispenser() {
    union() {
        backplate();
        left_side();
        right_side();
        cutter_bar();
    }
}

module backplate() {
    difference() {
        cube([X_size, wall_thick, Z_size]);
        
        // Wall mounting holes
        translate([X_size/4, -1, Z_size - 20])
            rotate([-90, 0, 0]) cylinder(d=5, h=wall_thick+2);
        translate([3*X_size/4, -1, Z_size - 20])
            rotate([-90, 0, 0]) cylinder(d=5, h=wall_thick+2);
        translate([X_size/4, -1, 20])
            rotate([-90, 0, 0]) cylinder(d=5, h=wall_thick+2);
        translate([3*X_size/4, -1, 20])
            rotate([-90, 0, 0]) cylinder(d=5, h=wall_thick+2);
    }
}

module side_panel() {
    difference() {
        hull() {
            // Bottom footprint
            cube([wall_thick, Y_size, wall_thick]);
            // Back wall
            cube([wall_thick, wall_thick, Z_size]);
            // Top flat section for the spindle slot
            translate([0, 0, Z_size - wall_thick])
                cube([wall_thick, spindle_y + 15, wall_thick]);
        }
        
        // U-slot for dropping in the spindle
        translate([-1, spindle_y, spindle_z]) {
            rotate([0, 90, 0]) cylinder(d=core_dia+4, h=wall_thick+2);
            translate([0, -(core_dia+4)/2, 0]) 
                cube([wall_thick+2, core_dia+4, Z_size]);
        }
    }
}

module left_side() {
    side_panel();
}

module right_side() {
    translate([X_size - wall_thick, 0, 0])
        side_panel();
}

module cutter_bar() {
    translate([0, Y_size - 15, 0]) {
        hull() {
            // Base of the cutter bar
            cube([X_size, 15, 2]);
            // Sharp cutting edge pointing up/backward
            translate([0, 14, wall_thick*1.5]) 
                cube([X_size, 1, 1]);
        }
    }
}

module spindle() {
    // Placed next to the dispenser for easy print-in-place
    translate([X_size + 30, Y_size/2, 0]) {
        // Bottom flange
        cylinder(d=core_dia + 10, h=wall_thick);
        
        // Main shaft
        cylinder(d=core_dia, h=X_size + 10);
        
        // Top flange (chamfered for support-free 3D printing)
        translate([0, 0, X_size + 10]) 
            cylinder(d1=core_dia, d2=core_dia + 10, h=wall_thick);
        translate([0, 0, X_size + 10 + wall_thick]) 
            cylinder(d=core_dia + 10, h=wall_thick);
    }
}