// Rendering a unified diff is a self-contained concern with its own size
// limits, kept out of views.js so that file stays within the project's
// architecture budget.
// A regenerated lock file runs into tens of thousands of lines, and one element
// per line freezes the window. Only the rendered view is capped.
const DIFF_RENDER_LINE_LIMIT = 2000;

function diffAtmosphere(diff, allLines = null) {
  if (!ui.selectedFile) return "";
  const lines = allLines || String(diff || "").split("\n");
  const additions = lines.filter(
    (line) => line.startsWith("+") && !line.startsWith("+++"),
  ).length;
  const removals = lines.filter(
    (line) => line.startsWith("-") && !line.startsWith("---"),
  ).length;
  const extension =
    String(ui.selectedFile).split(".").pop()?.slice(0, 8).toUpperCase() ||
    "FILE";
  return `<div class="diff-atmosphere ${lines.length > 34 ? "dense" : ""}" data-diff-atmosphere aria-hidden="true"><svg viewBox="0 0 360 260" role="presentation"><path class="code-route route-a" d="M38 195 C92 84 178 214 318 74"/><path class="code-route route-b" d="M52 74 C132 8 230 34 310 156"/><g class="code-card"><rect x="110" y="75" width="142" height="106" rx="18"/><path d="M136 108h90M136 128h58M136 148h76"/></g><g class="code-node node-one"><circle cx="48" cy="190" r="15"/><path d="m41 190 5 5 9-12"/></g><g class="code-node node-two"><circle cx="315" cy="76" r="13"/><path d="M308 76h14M315 69v14"/></g><circle class="code-packet packet-one" cx="0" cy="0" r="5"/><circle class="code-packet packet-two" cx="0" cy="0" r="4"/></svg><div class="diff-atmosphere-caption"><span>${escapeHtml(extension)} change map</span><strong><i>+${additions}</i><i>−${removals}</i></strong></div></div>`;
}

function diffLineType(line) {
  if (line.startsWith("+") && !line.startsWith("+++")) return "add";
  if (line.startsWith("-") && !line.startsWith("---")) return "remove";
  return line.startsWith("@@") ? "hunk" : "";
}

function renderDiff(diff) {
  if (!diff)
    return '<div class="empty-state"><div class="empty-icon">↔</div><h3>No textual diff</h3><p>Select another file or open the project folder for binary changes.</p></div>';
  const lines = String(diff).split("\n");
  const rendered = lines
    .slice(0, DIFF_RENDER_LINE_LIMIT)
    .map((line) => `<span class="diff-line ${diffLineType(line)}">${escapeHtml(line) || " "}</span>`)
    .join("");
  const hidden = Math.max(0, lines.length - DIFF_RENDER_LINE_LIMIT);
  const notice = hidden ? `<span class="diff-line hunk">… ${hidden.toLocaleString()} more line${hidden === 1 ? "" : "s"} are not shown. Copy diff and the editor still give you the complete change.</span>` : "";
  return `${rendered}${notice}${diffAtmosphere(diff, lines)}`;
}