$fn=64;

// --- Parameters ---
arm_length = 100;
arm_width = 16;
arm_thick = 10;
hole_d = 5.5; // Clearance for M5 bolts

desk_thick = 35;
clamp_depth = 40;
clamp_width = 20;
clamp_thick = 12;

lens_inner_d = 75;
lens_outer_d = 85;

// --- Print Layout ---
// Base clamp
translate([-80, 0, 0]) base_clamp();

// Lower Arm (Top / Bottom half-laps)
translate([0, -40, 0]) arm_segment(arm_length, "bottom");

// Upper Arm (Top / Top half-laps)
translate([0, -15, 0]) arm_segment(arm_length, "top");

// Lens Mount (Bottom half-lap)
translate([50, 60, 0]) lens_mount();

// Thumbwheels (6x for M5 bolts and nuts)
for(i=[0:2]) {
    translate([10 + i*30, -70, 0]) thumbwheel();
    translate([10 + i*30, -95, 0]) thumbwheel();
}

// --- Modules ---

module base_clamp() {
    difference() {
        union() {
            // Main C-clamp body
            cube([clamp_depth, desk_thick + clamp_thick*2, clamp_width]);
            // Joint hub extending UP (Acts as a Bottom half-lap)
            translate([clamp_depth/2, desk_thick + clamp_thick*1.5, clamp_width])
                cylinder(d=arm_width, h=arm_thick/2);
        }
        // Cutout for desk
        translate([-1, clamp_thick, -1])
            cube([clamp_depth + 2, desk_thick, clamp_width+2]);
        
        // Hole for tightening screw
        translate([clamp_depth/2, -1, clamp_width/2])
            rotate([-90, 0, 0])
            cylinder(d=hole_d, h=clamp_thick+2);
            
        // Nut trap for tightening screw (outside face, rotated for flat bridging)
        translate([clamp_depth/2, -0.1, clamp_width/2])
            rotate([-90, 30, 0])
            cylinder(d=9.6, h=4, $fn=6);
            
        // Hole for joint hub
        translate([clamp_depth/2, desk_thick + clamp_thick*1.5, -1])
            cylinder(d=hole_d, h=clamp_width + arm_thick + 2);
    }
}

module arm_segment(len, end2_type="bottom") {
    // Laid flat on its side to print without supports
    translate([0, arm_thick, arm_width/2]) rotate([90, 0, 0])
    difference() {
        union() {
            translate([0, -arm_width/2, 0]) cube([len, arm_width, arm_thick]);
            cylinder(d=arm_width, h=arm_thick);
            translate([len, 0, 0]) cylinder(d=arm_width, h=arm_thick);
        }
        
        // End 1: Cutout BOTTOM half -> leaves TOP half intact
        translate([-arm_width, -arm_width, -1]) 
            cube([arm_width*2, arm_width*2, arm_thick/2 + 1]);
        
        // End 2
        if (end2_type == "bottom") {
            // Cutout TOP half -> leaves BOTTOM half intact
            translate([len-arm_width, -arm_width, arm_thick/2]) 
                cube([arm_width*2, arm_width*2, arm_thick/2 + 1]);
        } else {
            // Cutout BOTTOM half -> leaves TOP half intact
            translate([len-arm_width, -arm_width, -1]) 
                cube([arm_width*2, arm_width*2, arm_thick/2 + 1]);
        }
        
        // Joint Holes
        translate([0, 0, -1]) cylinder(d=hole_d, h=arm_thick+2);
        translate([len, 0, -1]) cylinder(d=hole_d, h=arm_thick+2);
    }
}

module lens_mount() {
    hub_x = lens_outer_d/2 + 25;
    difference() {
        union() {
            // Lens ring
            cylinder(d=lens_outer_d, h=arm_thick);
            // Connecting block
            translate([lens_outer_d/2 - 2, -arm_width/2, 0])
                cube([hub_x - lens_outer_d/2 + 2, arm_width, arm_thick]);
            // Joint hub
            translate([hub_x, 0, 0])
                cylinder(d=arm_width, h=arm_thick);
        }
        // Lens hole
        translate([0, 0, -1]) cylinder(d=lens_inner_d, h=arm_thick+2);
        
        // Lens lip (drop-in from top)
        translate([0, 0, arm_thick/2]) cylinder(d=lens_inner_d + 4, h=arm_thick);
        
        // Hub Cutout TOP half -> leaves BOTTOM half intact
        translate([hub_x - arm_width, -arm_width, arm_thick/2])
            cube([arm_width*2, arm_width*2, arm_thick/2 + 1]);
            
        // Joint Hole
        translate([hub_x, 0, -1])
            cylinder(d=hole_d, h=arm_thick+2);
    }
}

module thumbwheel() {
    difference() {
        cylinder(d=25, h=8, $fn=6); // Hexagonal grip
        translate([0, 0, -1]) cylinder(d=hole_d, h=10); // Bolt pass-through
        translate([0, 0, 3.5]) cylinder(d=9.6, h=5, $fn=6); // M5 nut/bolt head trap
    }
}