const {chromium} = require('playwright');
const assert = require('node:assert/strict');
const fs = require('node:fs');

// Inspect the rendered paths, not just the authored JSON. Also runs on downloaded SVGs.
function inspect({mobile, xml}) {
  let svg = document.querySelector('svg[role="img"]');
  if (xml) {
    svg = new DOMParser().parseFromString(xml, 'image/svg+xml').documentElement;
    document.body.appendChild(svg);
  }
  const point = (element, p) => new DOMPoint(p.x, p.y).matrixTransform(element.getCTM());
  const boxes = [...svg.querySelectorAll('[data-node-id]')].map(node => {
    const rect = node.querySelector('rect'), box = rect.getBBox();
    const a = point(rect, box), b = point(rect, {x:box.x + box.width, y:box.y + box.height});
    return {id:node.dataset.nodeId, x:a.x, y:a.y, right:b.x, bottom:b.y, cx:(a.x+b.x)/2, cy:(a.y+b.y)/2};
  });
  const agent = boxes.find(n => n.id === 'agent');
  const errors = [], endpoints = {};
  const paths = [...svg.querySelectorAll('path[data-edge-id^="govern-"]')];
  if (paths.length !== 8) errors.push(`expected eight governance paths, got ${paths.length}`);
  for (const path of paths) {
    const id = path.dataset.edgeTo;
    const side = mobile ? 'left' : ['scope','architecture','releases'].includes(id) ? 'top'
      : ['planning','delivery','uat'].includes(id) ? 'bottom' : id === 'security' ? 'left' : 'right';
    const expected = {top:[agent.cx,agent.y],bottom:[agent.cx,agent.bottom],left:[agent.x,agent.cy],right:[agent.right,agent.cy]}[side];
    const start = point(path,path.getPointAtLength(0));
    endpoints[id] = [start.x,start.y];
    if (Math.hypot(start.x-expected[0],start.y-expected[1]) > 0.01) errors.push(`${id}: wrong ${side} midpoint`);
    const length = path.getTotalLength();
    for (let distance = 1; distance < length; distance += 2) {
      const p = point(path,path.getPointAtLength(distance));
      for (const box of boxes) {
        if (box.id === id) continue;
        if (p.x > box.x+0.1 && p.x < box.right-0.1 && p.y > box.y+0.1 && p.y < box.bottom-0.1) {
          errors.push(`${id}: crosses ${box.id}`); break;
        }
      }
    }
  }
  if (xml) svg.remove();
  return {errors:[...new Set(errors)],endpoints};
}

(async () => {
  const base = process.argv[2] || 'http://127.0.0.1:4173';
  const output = `.cache/midpoints-${process.argv[3] || 'local'}`;
  fs.mkdirSync(output,{recursive:true});
  const browser = await chromium.launch({headless:true, executablePath:process.env.PLAYWRIGHT_CHROMIUM_EXECUTABLE,args:['--no-sandbox']});
  const results = [];
  try {
    for (const width of [1440,390,320]) {
      const page = await browser.newPage({viewport:{width,height:1000}});
      await page.goto(`${base}/eldorado-v1/documentation/strategy/target-operating-model/`,{waitUntil:'networkidle'});
      const panel = page.locator('[data-diagram="strategy-target"]');
      const iframe = panel.locator(`:scope > .story-${width > 700 ? 'desktop' : 'mobile'}`);
      await iframe.scrollIntoViewIfNeeded();
      const frame = await (await iframe.elementHandle()).contentFrame();
      await frame.locator('svg[role="img"]').waitFor();
      const inline = await frame.evaluate(inspect,{mobile:width < 700});
      assert.deepEqual(inline.errors,[]);
      await page.screenshot({path:`${output}/${width}-inline.png`,fullPage:true});
      await frame.locator('#btn-export').click();
      const [download] = await Promise.all([page.waitForEvent('download'),frame.locator('[data-format="svg"]').click()]);
      assert.equal(await download.failure(),null);
      const path = `${output}/${width}.svg`;
      await download.saveAs(path);
      const exported = await frame.evaluate(inspect,{mobile:width < 700,xml:fs.readFileSync(path,'utf8')});
      assert.deepEqual(exported.errors,[]);
      await panel.getByRole('button',{name:/^Expand /}).click();
      const full = await (await panel.locator('dialog iframe').elementHandle()).contentFrame();
      await full.locator('svg[role="img"]').waitFor();
      // The existing fullscreen viewer always opens the radial desktop source.
      const fullscreen = await full.evaluate(inspect,{mobile:false});
      assert.deepEqual(fullscreen.errors,[]);
      await page.screenshot({path:`${output}/${width}-fullscreen.png`});
      await panel.getByRole('button',{name:'Close full-screen diagram'}).click();
      results.push({width,inline,exported,fullscreen});
      fs.writeFileSync(`${output}/results.json`,JSON.stringify(results,null,2));
      await page.close();
    }
    assert.equal(results.length,3);
    console.log('PASS midpoint geometry and no node crossings: 3 viewports × inline/fullscreen/exported SVG');
  } finally {await browser.close();}
})().catch(error => {console.error(error);process.exitCode=1;});