// You can find the Turtle API reference here: https://turtletoy.net/syntax
Canvas.setpenopacity(1);

const turtle = new Turtle();
const polygons = new Polygons();

const configs = [
    [
        [[30, 3, 5, 0], [0, 0]],
        [[16, 3, 5, 0], [51, 0]],
        [[7, 3, 5, 0], [53.5, -28.5]],
        [[16, 3, 5, 0], [-39.5, 32]],
        [[30, 3, 5, 0], [-91, 39]],
    ],
    [
        [[18, 10, 8, 0], [53.5, -28.5]],
        [[8, 10, 8, Math.PI / 5.6], [-38, -44]],
        [[28, 10, 8, Math.PI / 5.6], [-122, 48.5]],
        [[28, 10, 8, Math.PI / 5], [-110.5, -147]],
    ],
    [
        [[6, 10, 15, Math.PI/3.65], [38.3, 85]],
        [[16, 10, 15, Math.PI/3.1], [125, 95]],
    ],
    [
        [[150, 2, 2, 0], [-38, -44]],
        [[80, 2, 2, Math.PI/3.1], [38.3, 85]],
        [[80, 2, 2, Math.PI/3.1], [111.5, -44.5]],
        [[15, 2, 2, 0], [-25, 81]],
    ],
    [
        [[25, 2, 2, 0], [-25, 81]],
        [[25, 2, 2, 0], [-54.5, 99.5]],
    ]
];

for (const gearset of configs) {
    for (const gear of gearset) {
        drawPolygon(getGearPts(...gear[0]), gear[1]);
    }
}

function add2(a,b){return [a[0]+b[0],a[1]+b[1]];}
function sub2(a,b){return [a[0]-b[0],a[1]-b[1]];}
function scale2(a,s){return [a[0]*s,a[1]*s];}
function rot2(a) { return [Math.cos(a), -Math.sin(a), Math.sin(a), Math.cos(a)]; }
function trans2(m, a) { return [m[0]*a[0]+m[2]*a[1], m[1]*a[0]+m[3]*a[1]]; } //Matrix(2x1) x Matrix(2x2)
function draw(path, position) {
    [...path, path[0]].forEach((pt, i) => turtle[i == 0? 'jump': 'goto'](add2(pt, position)));
}
function drawPolygon(path, position, hatch = [], addHoles = true) {
    if(addHoles) {
        const limits = path.reduce((p, c) => [
            [Math.min(c[0], p[0][0]), Math.max(c[0], p[0][1])],
            [Math.min(c[1], p[1][0]), Math.max(c[1], p[1][1])],
        ], [[0,0],[0,0]]);
        
        const center = [limits[0][1] - limits[0][0], limits[1][1] - limits[1][0]];
        const r = Math.min(6, .1 * (limits[0][1] - limits[0][0]));
        
        drawPolygon(circlePoints(r), position, [[1, 1], [2, 1]], false);
    }
    
    const p = polygons.create();
    p.addPoints(...path.map(pt => add2(position, pt)));
    p.addOutline();
    hatch.forEach(h => p.addHatching(...h))
    polygons.draw(turtle, p);
}

function circlePoints(radius, extend = 2 * Math.PI, clockWiseStart = 0, steps = null, includeLast = false) { return [steps == null? (radius*extend+1)|0: steps].map(steps => Array.from({length: steps}).map((v, i, a) => [radius * Math.cos(clockWiseStart + extend*i/(a.length-(includeLast?1:0))), radius * Math.sin(clockWiseStart + extend*i/(a.length-(includeLast?1:0)))])).pop(); }

function getGearPts(teeth, toothWidth, toothHeight, startPhase = 0) {
    const cummInteriorAngle = ((teeth * 2) - 2) * Math.PI;
    const r = (toothWidth / 2) / Math.cos(cummInteriorAngle / (teeth * 2) / 2);
    return Array.from({length: teeth * 2}).map((v, i, a) => [
        r * Math.cos(startPhase + 2 * Math.PI * i / a.length),
        r * Math.sin(startPhase + 2 * Math.PI * i / a.length)
    ]).flatMap((v, i, a) => i % 2 == 0?
        [scale2(trans2([0, -1, 1, 0], sub2(a[i+1], v)), toothHeight/toothWidth)].map(vec =>
            [v, add2(v, vec), add2(a[i+1], vec)]
        ).pop(): [v]
    );
}


////////////////////////////////////////////////////////////////
// Polygon Clipping utility code - Created by Reinder Nijhoff 2019
// (Polygon binning by Lionel Lemarie 2021)
// https://turtletoy.net/turtle/a5befa1f8d
////////////////////////////////////////////////////////////////
function Polygons(){const t=[],s=25,e=Array.from({length:s**2},t=>[]),n=class{constructor(){this.cp=[],this.dp=[],this.aabb=[]}addPoints(...t){let s=1e5,e=-1e5,n=1e5,h=-1e5;(this.cp=[...this.cp,...t]).forEach(t=>{s=Math.min(s,t[0]),e=Math.max(e,t[0]),n=Math.min(n,t[1]),h=Math.max(h,t[1])}),this.aabb=[s,n,e,h]}addSegments(...t){t.forEach(t=>this.dp.push(t))}addOutline(){for(let t=0,s=this.cp.length;t<s;t++)this.dp.push(this.cp[t],this.cp[(t+1)%s])}draw(t){for(let s=0,e=this.dp.length;s<e;s+=2)t.jump(this.dp[s]),t.goto(this.dp[s+1])}addHatching(t,s){const e=new n;e.cp.push([-1e5,-1e5],[1e5,-1e5],[1e5,1e5],[-1e5,1e5]);const h=Math.sin(t)*s,o=Math.cos(t)*s,a=200*Math.sin(t),i=200*Math.cos(t);for(let t=.5;t<150/s;t++)e.dp.push([h*t+i,o*t-a],[h*t-i,o*t+a]),e.dp.push([-h*t+i,-o*t-a],[-h*t-i,-o*t+a]);e.boolean(this,!1),this.dp=[...this.dp,...e.dp]}inside(t){let s=0;for(let e=0,n=this.cp.length;e<n;e++)this.segment_intersect(t,[.1,-1e3],this.cp[e],this.cp[(e+1)%n])&&s++;return 1&s}boolean(t,s=!0){const e=[];for(let n=0,h=this.dp.length;n<h;n+=2){const h=this.dp[n],o=this.dp[n+1],a=[];for(let s=0,e=t.cp.length;s<e;s++){const n=this.segment_intersect(h,o,t.cp[s],t.cp[(s+1)%e]);!1!==n&&a.push(n)}if(0===a.length)s===!t.inside(h)&&e.push(h,o);else{a.push(h,o);const n=o[0]-h[0],i=o[1]-h[1];a.sort((t,s)=>(t[0]-h[0])*n+(t[1]-h[1])*i-(s[0]-h[0])*n-(s[1]-h[1])*i);for(let n=0;n<a.length-1;n++)(a[n][0]-a[n+1][0])**2+(a[n][1]-a[n+1][1])**2>=.001&&s===!t.inside([(a[n][0]+a[n+1][0])/2,(a[n][1]+a[n+1][1])/2])&&e.push(a[n],a[n+1])}}return(this.dp=e).length>0}segment_intersect(t,s,e,n){const h=(n[1]-e[1])*(s[0]-t[0])-(n[0]-e[0])*(s[1]-t[1]);if(0===h)return!1;const o=((n[0]-e[0])*(t[1]-e[1])-(n[1]-e[1])*(t[0]-e[0]))/h,a=((s[0]-t[0])*(t[1]-e[1])-(s[1]-t[1])*(t[0]-e[0]))/h;return o>=0&&o<=1&&a>=0&&a<=1&&[t[0]+o*(s[0]-t[0]),t[1]+o*(s[1]-t[1])]}};return{list:()=>t,create:()=>new n,draw:(n,h,o=!0)=>{reducedPolygonList=function(n){const h={},o=200/s;for(var a=0;a<s;a++){const c=a*o-100,r=[0,c,200,c+o];if(!(n[3]<r[1]||n[1]>r[3]))for(var i=0;i<s;i++){const c=i*o-100;r[0]=c,r[2]=c+o,n[0]>r[2]||n[2]<r[0]||e[i+a*s].forEach(s=>{const e=t[s];n[3]<e.aabb[1]||n[1]>e.aabb[3]||n[0]>e.aabb[2]||n[2]<e.aabb[0]||(h[s]=1)})}}return Array.from(Object.keys(h),s=>t[s])}(h.aabb);for(let t=0;t<reducedPolygonList.length&&h.boolean(reducedPolygonList[t]);t++);h.draw(n),o&&function(n){t.push(n);const h=t.length-1,o=200/s;e.forEach((t,e)=>{const a=e%s*o-100,i=(e/s|0)*o-100,c=[a,i,a+o,i+o];c[3]<n.aabb[1]||c[1]>n.aabb[3]||c[0]>n.aabb[2]||c[2]<n.aabb[0]||t.push(h)})}(h)}}}