import {readFileSync} from 'node:fs';
import assert from 'node:assert/strict';
import {test} from 'node:test';
import ts from 'typescript';
const source=readFileSync(new URL('../src/lib/latency-marker.ts',import.meta.url),'utf8');
const code=ts.transpileModule(source,{compilerOptions:{module:ts.ModuleKind.CommonJS,target:ts.ScriptTarget.ES2022}}).outputText;
const exports={};new Function('exports',code)(exports);
const {drawMarker,decodeMarker}=exports;
function image(counter,w=320,h=240) {
  const pixels=new Uint8ClampedArray(w*h*4);
  const ctx={canvas:{width:w,height:h},fillStyle:'',fillRect(x,y,width,height){
    const c=this.fillStyle.startsWith('rgb(')?this.fillStyle.slice(4,-1).split(',').map(Number):
      this.fillStyle==='#fff'?[255,255,255]:this.fillStyle==='#000'?[0,0,0]:[60,60,60];
    for(let yy=Math.max(0,Math.ceil(y));yy<Math.min(h,y+height);yy++)
      for(let xx=Math.max(0,Math.ceil(x));xx<Math.min(w,x+width);xx++)pixels.set([...c,255],(yy*w+xx)*4);
  }};
  drawMarker(ctx,counter);return pixels;
}
test('screen IDs decode at Gray-code boundaries and across counter wrap',()=>{
  for(const id of [0,1,2,3,63,127,1023,2047,2048,4094,4095,4096]) {
    assert.equal(decodeMarker(image(id),320,240)?.counter,id&4095);
  }
});
test('camera rotation and reflection preserve the observed ID',()=>{
  const original=image(1371),rotated=new Uint8ClampedArray(original.length),flipped=new Uint8ClampedArray(original.length);
  for(let y=0;y<240;y++)for(let x=0;x<320;x++){
    rotated.set(original.subarray((y*320+x)*4,(y*320+x)*4+4),(x*240+239-y)*4);
    flipped.set(original.subarray((y*320+x)*4,(y*320+x)*4+4),(y*320+319-x)*4);
  }
  assert.equal(decodeMarker(rotated,240,320)?.counter,1371);
  assert.equal(decodeMarker(flipped,320,240)?.counter,1371);
});
test('missing fiducials and ambiguous rolling transitions do not invent latency samples',()=>{
  assert.equal(decodeMarker(new Uint8ClampedArray(320*240*4),320,240),null);
  const pixels=image(123);
  for(let y=90;y<152;y++)for(let x=44;x<276;x++)pixels.set([128,128,128,255],(y*320+x)*4);
  assert.equal(decodeMarker(pixels,320,240),null);
});

test('washed screen primaries survive without mistaking a blue-tinted background',()=>{
  const pixels=image(1371);
  for(let i=0;i<pixels.length;i+=4){
    const r=pixels[i],g=pixels[i+1],b=pixels[i+2];
    if(r===32&&g===255&&b===32)pixels.set([190,255,208,255],i);
    else if(r===32&&g===96&&b===255)pixels.set([78,205,255,255],i);
    else if(r===255&&g===32&&b===255)pixels.set([255,112,255,255],i);
    else if(r===60&&g===60&&b===60)pixels.set([165,181,225,255],i);
  }
  assert.equal(decodeMarker(pixels,320,240)?.counter,1371);
});