examples/hanzo-app/apps/redline.html

<!--hz {"title":"Review","archetype":"devtool / code review","creator":"data","desc":"Code review tool: a real line-level diff engine (LCS) over two revisions, unified and split views, per-line comments, review state, file tree with per-file statistics and a patch export.","nav":[["#/","Review"]]} -->
<div class="row" style="margin-bottom:12px">
  <h1 style="margin:0">Review</h1><span class="tag" id="stat"></span>
  <span class="spacer"></span>
  <span id="modes" class="row" style="gap:4px"></span>
  <button id="patch">Export patch</button>
  <button class="p" id="approve">Approve</button>
</div>
<div class="split">
  <div class="pane"><header>Files changed</header><ul class="list" id="files"></ul>
    <div class="body"><p class="hz-note" style="margin:0">The diff is computed here by a longest-common-subsequence pass over the two revisions — not pre-baked. Edit either side and it recomputes.</p></div></div>
  <div class="col"><div id="view"></div>
    <div class="pane"><header>Edit revisions</header><div class="body split" style="gap:10px">
      <div><label>Before</label><textarea id="a" style="min-height:150px;font-family:var(--mono);font-size:12px"></textarea></div>
      <div><label>After</label><textarea id="b" style="min-height:150px;font-family:var(--mono);font-size:12px"></textarea></div>
    </div></div>
  </div>
</div>
<script>
const {h,fill,$,store,fmt,tabs,toast,submit,route} = hz;
const FILES = {
 'clients/projects/release.go': [
`func activate(ctx context.Context, slug, id string) error {
	rel, err := store.Release(ctx, slug, id)
	if err != nil {
		return err
	}
	return store.SetActive(ctx, slug, rel.ID)
}`,
`func activate(ctx context.Context, slug, id string) error {
	rel, err := store.Release(ctx, slug, id)
	if err != nil {
		return err
	}
	// Verify the bytes before flipping the pointer: an activation that
	// promotes a partially uploaded release is worse than a failed deploy,
	// because it looks like it worked.
	if err := store.VerifyBytes(ctx, rel); err != nil {
		return fmt.Errorf("activate %s: %w", id, err)
	}
	return store.SetActive(ctx, slug, rel.ID)
}`],
 'clients/sites/reserved.go': [
`var baseReserved = []string{
	"api", "admin", "docs", "status",
}`,
`var baseReserved = []string{
	"api", "admin", "docs", "status",
	// Keep in lock-step with the shared client's OAuth redirect labels:
	// a publishable label that the client already trusts is an account
	// takeover, not a naming collision.
	"www", "stg",
}`],
 'kit/hz.js': [
`function store(key, initial) {
  let val = initial;
  return { get: () => val, set(v) { val = v; } };
}`,
`function store(key, initial) {
  const k = 'hz:' + key, subs = new Set();
  let val = initial;
  try { const raw = localStorage.getItem(k); if (raw != null) val = JSON.parse(raw); } catch (e) {}
  const save = () => { try { localStorage.setItem(k, JSON.stringify(val)); } catch (e) {} };
  return {
    get: () => val,
    set(v) { val = typeof v === 'function' ? v(val) : v; save(); subs.forEach(f => f(val)); return val; },
    sub(f) { subs.add(f); f(val); return () => subs.delete(f); },
  };
}`],
};
const comments = store('review.comments', {});
const approved = store('review.approved', false);
const view = $('#view');
let cur = Object.keys(FILES)[0], mode = 'Unified';

function lcsDiff(A, B){
  const m = Array.from({length:A.length+1},()=>new Uint16Array(B.length+1));
  for(let i=A.length-1;i>=0;i--) for(let j=B.length-1;j>=0;j--)
    m[i][j] = A[i]===B[j] ? m[i+1][j+1]+1 : Math.max(m[i+1][j], m[i][j+1]);
  const out=[]; let i=0,j=0;
  while(i<A.length && j<B.length){
    if(A[i]===B[j]) out.push({op:' ', a:i+1, b:j+1, t:A[i++]}), j++;
    else if(m[i+1][j] >= m[i][j+1]) out.push({op:'-', a:i+1, b:null, t:A[i++]});
    else out.push({op:'+', a:null, b:j+1, t:B[j++]});
  }
  while(i<A.length) out.push({op:'-', a:i+1, b:null, t:A[i++]});
  while(j<B.length) out.push({op:'+', a:null, b:j+1, t:B[j++]});
  return out;
}
const diffOf = f => lcsDiff(FILES[f][0].split('\n'), FILES[f][1].split('\n'));
function counts(f){ const d=diffOf(f);
  return {add:d.filter(x=>x.op==='+').length, del:d.filter(x=>x.op==='-').length}; }
function files(){
  const tot = Object.keys(FILES).reduce((a,f)=>{ const c=counts(f); return {add:a.add+c.add, del:a.del+c.del}; },{add:0,del:0});
  $('#stat').textContent = Object.keys(FILES).length+' files · +'+tot.add+' −'+tot.del +
    (approved.get()? ' · approved' : '');
  $('#stat').className = 'tag '+(approved.get()?'ok':'');
  fill($('#files'), Object.keys(FILES).map(f=>{ const c=counts(f);
    const n = Object.keys(comments.get()).filter(k=>k.startsWith(f+':')).length;
    return h('li',{style:{cursor:'pointer',background:f===cur?'var(--bg3)':''},
      onclick:()=>{cur=f; load(); render();}},
      h('div',{style:{minWidth:0}}, h('div.mono.small.trunc',f.split('/').pop()),
        h('div.small.muted.trunc',f)),
      h('span.spacer'),
      n? h('span.tag.acc',n+'💬'):null,
      h('span.small.up','+'+c.add), h('span.small.down','−'+c.del)); }));
}
function lineRow(l, side){
  const key = cur+':'+(l.b||('a'+l.a));
  const cm = comments.get()[key];
  const bg = l.op==='+'? 'rgba(62,207,142,.10)' : l.op==='-'? 'rgba(244,104,94,.10)' : '';
  const row = h('div',{style:{display:'grid',gridTemplateColumns:'46px 46px 14px 1fr',
    fontFamily:'var(--mono)',fontSize:'12.5px',lineHeight:'1.65',background:bg,cursor:'pointer'},
    onclick:()=>comment(key)},
    h('span.muted',{style:{textAlign:'right',paddingRight:'8px',opacity:.6}}, l.a??''),
    h('span.muted',{style:{textAlign:'right',paddingRight:'8px',opacity:.6}}, l.b??''),
    h('span',{style:{color: l.op==='+'?'var(--ok)':l.op==='-'?'var(--bad)':'var(--fg3)'}}, l.op),
    h('span',{style:{whiteSpace:'pre-wrap',paddingLeft:'6px'}}, l.t || ' '));
  return cm ? h('div', row, h('div.card.tight',{style:{margin:'4px 0 4px 106px',borderColor:'var(--acc)'}},
    h('div.small.b','Reviewer note'), h('div.small',cm),
    h('button.g.sm',{style:{marginTop:'4px'},onclick:e=>{e.stopPropagation();
      comments.set(v=>{const n={...v}; delete n[key]; return n;}); render();}},'Resolve'))) : row;
}
function comment(key){
  const t = prompt('Comment on this line'); if(!t) return;
  comments.set(v=>({...v,[key]:t})); files(); render();
  submit('review.comment',{file:cur, line:key.split(':')[1], body:t}).catch(()=>{});
}
function render(){
  const d = diffOf(cur);
  if(mode==='Unified'){
    fill(view, h('div.pane', h('header',cur,h('span.spacer'),
        h('span.small.up','+'+counts(cur).add),h('span.small.down','−'+counts(cur).del)),
      h('div',{style:{padding:'10px 0',overflow:'auto'}}, d.map(l=>lineRow(l)))));
  } else {
    const left = d.filter(l=>l.op!=='+'), right = d.filter(l=>l.op!=='-');
    fill(view, h('div.pane', h('header',cur+' — split'),
      h('div.split',{style:{gap:'0',padding:'10px 0'}},
        h('div',{style:{overflow:'auto',borderRight:'1px solid var(--line)'}}, left.map(l=>lineRow(l))),
        h('div',{style:{overflow:'auto'}}, right.map(l=>lineRow(l))))));
  }
}
function load(){ $('#a').value = FILES[cur][0]; $('#b').value = FILES[cur][1]; }
['#a','#b'].forEach((s,i)=>$(s).addEventListener('input', ()=>{
  FILES[cur][i] = $(s).value; files(); render(); }));
$('#patch').onclick = () => {
  const patch = Object.keys(FILES).map(f=>{
    const d = lcsDiff(FILES[f][0].split('\n'), FILES[f][1].split('\n'));
    return '--- a/'+f+'\n+++ b/'+f+'\n' + d.map(l=>l.op+l.t).join('\n');
  }).join('\n\n');
  h('a',{download:'review.patch',href:URL.createObjectURL(new Blob([patch],{type:'text/plain'}))}).click();
  toast('Patch exported');
};
$('#approve').onclick = async () => {
  approved.set(!approved.get()); files();
  if(approved.get()){
    try{ await submit('review.approve',{files:Object.keys(FILES).length,
      comments:Object.keys(comments.get()).length}); toast('Review approved and recorded'); }
    catch(e){ toast('Approved locally'); }
  } else toast('Approval withdrawn');
};
fill($('#modes'), tabs(['Unified','Split'], m=>{mode=m; render();}));
route({'*':()=>{}});
files(); load(); render();
</script>