import fs from "fs";
import path from "path";
import { NextResponse } from "next/server";

let cachedFieldnotes = null;

async function getFieldnotes() {
  if (cachedFieldnotes) return cachedFieldnotes;
  
  try {
    const filePath = path.join(process.cwd(), "public/consolidated_fieldnotes.json");
    const data = await fs.promises.readFile(filePath, "utf8");
    const parsed = JSON.parse(data);
    
    // Drop the heavy lexical JSON representation on the server to keep memory and transfer size small
    cachedFieldnotes = parsed.map((note) => ({
      title: note.title,
      slug: note.slug,
      date: note.date,
      author_slug: note.author_slug,
      content_markdown: note.content_markdown || "",
    }));
    
    return cachedFieldnotes;
  } catch (error) {
    console.error("Error loading consolidated fieldnotes:", error);
    return [];
  }
}

export async function GET(request) {
  const { searchParams } = new URL(request.url);
  const query = searchParams.get("q") || "";
  const author = searchParams.get("author") || "";
  const tag = searchParams.get("tag") || "";

  const notes = await getFieldnotes();

  // Perform search
  let filtered = notes;

  if (author) {
    filtered = filtered.filter((n) => n.author_slug === author);
  }

  if (tag) {
    // Alchemical tags like 🜏, 🜁, etc.
    filtered = filtered.filter((n) => n.content_markdown.includes(tag));
  }

  if (query) {
    const lowerQuery = query.toLowerCase();
    filtered = filtered.filter(
      (n) =>
        n.title.toLowerCase().includes(lowerQuery) ||
        n.content_markdown.toLowerCase().includes(lowerQuery)
    );
  }

  // Slice results to keep response sizes fast
  const results = filtered.slice(0, 15);

  return NextResponse.json({
    total: filtered.length,
    results,
  });
}