content.js

chrome.runtime.onMessage.addListener((msg, sender, sendResponse) => {
  if (msg.type === "getContext") {
    const selection = window.getSelection();
    if (!selection.rangeCount) {
      sendResponse({ context: "" });
      return;
    }

    const range = selection.getRangeAt(0);
    let container = range.commonAncestorContainer;
    if (container.nodeType === Node.TEXT_NODE) {
      container = container.parentElement;
    }

    const blockTags = new Set([
      "P", "DIV", "ARTICLE", "SECTION", "LI", "BLOCKQUOTE",
      "TD", "TH", "H1", "H2", "H3", "H4", "H5", "H6", "PRE",
    ]);
    let block = container;
    while (block && !blockTags.has(block.tagName)) {
      block = block.parentElement;
    }

    const contextText = (block || container).innerText || "";
    sendResponse({ context: contextText.slice(0, 2000) });
    return;
  }

  if (msg.type === "getPageContent") {
    const content = extractPageContent();
    sendResponse({ content });
    return;
  }
});

function extractPageContent() {
  const selectors = ["article", '[role="main"]', "main", ".post-content", ".article-content", ".entry-content"];
  for (const sel of selectors) {
    const el = document.querySelector(sel);
    if (el && el.innerText.trim().length > 200) {
      return el.innerText.trim().slice(0, 12000);
    }
  }
  const body = document.body.cloneNode(true);
  for (const tag of body.querySelectorAll("nav, header, footer, aside, script, style, .sidebar, .comments")) {
    tag.remove();
  }
  return (body.innerText || "").trim().slice(0, 12000);
}