/**
 * Checks all general question MDX files under ippan-situmon to find
 * `####` sub-headings that are NOT in the QuestionSummary component.
 */
const fs = require("fs");
const path = require("path");

const BASE = path.resolve(__dirname, "..", "src/content/docs/ippan-situmon");

function findMdxFiles(dir) {
  const results = [];
  const entries = fs.readdirSync(dir, { withFileTypes: true });
  for (const entry of entries) {
    const fullPath = path.join(dir, entry.name);
    if (entry.isDirectory()) {
      results.push(...findMdxFiles(fullPath));
    } else if (
      entry.name.endsWith(".mdx") &&
      entry.name !== "index.mdx" &&
      entry.name !== "_partial.mdx"
    ) {
      results.push(fullPath);
    }
  }
  return results;
}

// Parse anchor values from a QuestionSummary qa array
function parseAnchors(content) {
  const anchorRegex = /anchor:\s*"([^"]+)"/g;
  const anchors = [];
  let match;
  while ((match = anchorRegex.exec(content)) !== null) {
    anchors.push(match[1]);
  }
  return anchors;
}

// Parse `####` headings from MDX content
function parseH4Headings(content) {
  const headingRegex = /^####\s+(.+?)(?:\s*\{[^}]*\})?\s*$/gm;
  const headings = [];
  let match;
  while ((match = headingRegex.exec(content)) !== null) {
    const raw = match[1].trim();
    headings.push(raw);
  }
  return headings;
}

// Generate Starlight-style anchor ID from heading text
function toAnchorId(text) {
  return text
    .toLowerCase()
    .replace(/<[^>]+>/g, "") // remove HTML tags
    .replace(
      /[^\w\s\-\u3040-\u309f\u30a0-\u30ff\u4e00-\u9fffぁ-んァ-ン一-龯ー・〜？！。、（）「」【】]/g,
      "",
    )
    .replace(/\s+/g, "-")
    .replace(/-+/g, "-")
    .replace(/^-|-$/g, "");
}

// Check if a heading matches any anchor
function headingMatchesAnchor(heading, anchors) {
  const headingId = toAnchorId(heading);

  for (const anchor of anchors) {
    // Exact match
    if (anchor === heading) return true;

    // Anchor ID match
    if (anchor === headingId) return true;

    // Anchor prefixed with "-"
    if (anchor === `-${heading}`) return true;
    if (anchor === `-${headingId}`) return true;

    // Anchor that starts with "-" - check if headingId matches after "-"
    if (anchor.startsWith("-")) {
      const afterDash = anchor.substring(1);
      if (afterDash === headingId || afterDash === heading) return true;
    }

    // Headings sometimes have HTML in them (like <sub>)
    // Strip HTML from heading and compare to anchor
    const headingPlain = heading.replace(/<[^>]+>/g, "");
    const headingPlainId = toAnchorId(headingPlain);

    if (anchor === headingPlain) return true;
    if (anchor === headingPlainId) return true;
    if (anchor === `-${headingPlain}`) return true;
    if (anchor === `-${headingPlainId}`) return true;
    if (anchor.startsWith("-") && anchor.substring(1) === headingPlainId)
      return true;
  }
  return false;
}

function main() {
  const files = findMdxFiles(BASE).sort();
  const results = [];

  for (const file of files) {
    const content = fs.readFileSync(file, "utf-8");
    const h4Headings = parseH4Headings(content);
    const anchors = parseAnchors(content);

    if (h4Headings.length === 0) continue;

    const relPath = path.relative(process.cwd(), file);
    const missing = [];

    for (const heading of h4Headings) {
      if (!headingMatchesAnchor(heading, anchors)) {
        missing.push(heading);
      }
    }

    results.push({
      file: relPath,
      totalH4: h4Headings.length,
      totalAnchors: anchors.length,
      missing,
      allPresent: missing.length === 0,
    });
  }

  // Output results
  console.log("=".repeat(80));
  console.log("ANALYSIS: #### headings NOT in QuestionSummary");
  console.log("=".repeat(80));
  console.log();

  let filesWithMissing = 0;
  let totalMissing = 0;

  for (const r of results) {
    if (r.missing.length === 0) continue;

    filesWithMissing++;
    totalMissing += r.missing.length;

    if (r.totalAnchors === 0) {
      console.log(`❌ ${r.file}`);
      console.log(
        `   Has ${r.totalH4} '####' headings but NO QuestionSummary component.`,
      );
      console.log();
      continue;
    }

    console.log(
      `⚠️  ${r.file}  [${r.totalAnchors} anchors, ${r.missing.length}/${r.totalH4} headings missing]`,
    );
    for (const m of r.missing) {
      console.log(`     #### ${m}`);
    }
    console.log();
  }

  console.log("=".repeat(80));
  console.log(`SUMMARY:`);
  console.log(`  Files with missing headings:          ${filesWithMissing}`);
  console.log(
    `  Files entirely missing QuestionSummary: ${results.filter((r) => r.totalAnchors === 0 && r.totalH4 > 0).length}`,
  );
  console.log(
    `  Files fully in sync:                  ${results.filter((r) => r.allPresent && r.totalAnchors > 0).length}`,
  );
  console.log(`  Total missing headings:               ${totalMissing}`);
  console.log(`  Total files analyzed:                 ${results.length}`);
  console.log("=".repeat(80));
}

main();