$fn=64;

// --- Parameters ---
drill_dia = 48;          // Inner diameter for drill chuck/nose
wall = 5;                // Wall thickness
holster_len = 85;        // Length of the holster tube
angle = 30;              // Mounting angle (degrees from vertical)

back_w = 90;             // Backplate width
back_h = 140;            // Backplate height
back_t = 8;              // Backplate thickness
corner_r = 5;            // Corner radius for backplate

bit_dia = 7.5;           // Hole size for 1/4" hex bits (includes clearance)
bit_depth = 12;          // Depth of bit holes
num_bits = 5;            // Number of bit storage holes

outer_dia = drill_dia + wall*2;

// --- Helper Module ---
module rounded_rect(w, h, t, r) {
    hull() {
        for(x = [-w/2+r, w/2-r]) {
            for(y = [-h/2+r, h/2-r]) {
                translate([x, y, 0]) cylinder(r=r, h=t);
            }
        }
    }
}

// --- Main Model ---
module holster() {
    difference() {
        union() {
            // Main backplate
            rounded_rect(back_w, back_h, back_t, corner_r);

            // Bit storage block (integrated at the bottom)
            translate([0, -back_h/2 + 15, 0])
                rounded_rect(back_w, 30, back_t + 16, corner_r);

            // Holster tube
            translate([0, -15, back_t])
                rotate([-angle, 0, 0])
                    cylinder(h=holster_len, d=outer_dia);
        }

        // Flatten the back (removes any tube protrusion below the backplate)
        translate([0, 0, -50])
            cube([back_w*2, back_h*2, 100], center=true);

        // Hollow out the holster tube for the drill chuck
        translate([0, -15, back_t])
            rotate([-angle, 0, 0])
                translate([0, 0, wall]) // Leave a solid base lip
                    cylinder(h=holster_len + 10, d=drill_dia);

        // Pass-through hole at the bottom for attached drill bits
        translate([0, -15, back_t])
            rotate([-angle, 0, 0])
                translate([0, 0, -10])
                    cylinder(h=wall + 20, d=25);

        // Slot for the drill handle (cutout on the side facing away from the wall)
        translate([0, -15, back_t])
            rotate([-angle, 0, 0])
                translate([0, -outer_dia/2, holster_len/2 + 20])
                    cube([drill_dia * 0.85, outer_dia, holster_len], center=true);

        // Bit storage holes
        for(i = [0 : num_bits-1]) {
            spacing = (back_w - 20) / (num_bits - 1);
            x_pos = -back_w/2 + 10 + i*spacing;
            
            // Main bit hole
            translate([x_pos, -back_h/2 + 15, back_t + 16 - bit_depth])
                cylinder(h=bit_depth + 2, d=bit_dia);
                
            // Chamfer for easy insertion
            translate([x_pos, -back_h/2 + 15, back_t + 16 - 1])
                cylinder(h=1.05, d1=bit_dia, d2=bit_dia + 2.5);
        }

        // Countersunk mounting holes
        hole_x = back_w/2 - 12;
        hole_y_top = back_h/2 - 12;
        hole_y_bot = -back_h/2 + 45;

        for(x = [-hole_x, hole_x]) {
            for(y = [hole_y_top, hole_y_bot]) {
                translate([x, y, -1]) {
                    // Screw shaft
                    cylinder(h=back_t + 20, d=5); 
                    // Countersink
                    translate([0, 0, back_t - 2])
                        cylinder(h=3, d1=5, d2=11);
                    // Screw head clearance
                    translate([0, 0, back_t + 0.9])
                        cylinder(h=10, d=11);
                }
            }
        }
    }
}

// Render the model (oriented flat on its back for 3D printing)
holster();