import { NextRequest, NextResponse } from "next/server";
import { mkdir, writeFile, readFile } from "node:fs/promises";
import { existsSync } from "node:fs";
import { join } from "node:path";

const DATA_DIR = "/app/data";
const FEEDBACK_FILE = join(DATA_DIR, "feedback.jsonl");

interface FeedbackEntry {
  id: string;
  timestamp: string;
  url: string;
  error: string;
  message: string;
  userAgent: string;
}

function generateId(): string {
  const ts = Date.now().toString(36);
  const rand = Math.random().toString(36).substring(2, 8);
  return `fb-${ts}-${rand}`;
}

function sanitizeUA(ua: string): string {
  // Strip personal info from UA string
  return ua.replace(/\(.*?\)/g, "(redacted)").substring(0, 200);
}

export async function POST(request: NextRequest) {
  try {
    const body = await request.json();
    const { url, error, message, userAgent } = body;

    if (!url || !error) {
      return NextResponse.json(
        { error: "url and error are required" },
        { status: 400 }
      );
    }

    const entry: FeedbackEntry = {
      id: generateId(),
      timestamp: new Date().toISOString(),
      url: url.substring(0, 500),
      error: error.substring(0, 1000),
      message: (message || "").substring(0, 2000),
      userAgent: sanitizeUA(userAgent || ""),
    };

    // Ensure data dir exists
    await mkdir(DATA_DIR, { recursive: true });

    // Append to JSONL file
    await writeFile(FEEDBACK_FILE, JSON.stringify(entry) + "\n", {
      flag: "a",
    });

    return NextResponse.json({ id: entry.id });
  } catch (err) {
    // Silent failure — don't throw errors from error-reporting endpoint
    console.error("Feedback save error:", err);
    return NextResponse.json({ id: null }, { status: 200 });
  }
}

export async function GET(request: NextRequest) {
  // Admin-only endpoint — return paginated feedback
  const authHeader = request.headers.get("authorization") || "";
  const adminToken = process.env.FEEDBACK_ADMIN_TOKEN;

  // Require token to be set in production
  if (!adminToken) {
    if (process.env.NODE_ENV === "production") {
      console.error("FEEDBACK_ADMIN_TOKEN not configured");
      return NextResponse.json({ error: "Server configuration error" }, { status: 500 });
    }
    // Dev fallback only
    return NextResponse.json({ error: "Unauthorized — configure FEEDBACK_ADMIN_TOKEN" }, { status: 401 });
  }

  // Simple token auth
  if (authHeader !== `Bearer ${adminToken}`) {
    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
  }

  const { searchParams } = new URL(request.url);
  const limit = Math.min(parseInt(searchParams.get("limit") || "50"), 200);
  const offset = parseInt(searchParams.get("offset") || "0");

  try {
    if (!existsSync(FEEDBACK_FILE)) {
      return NextResponse.json({ entries: [], total: 0 });
    }

    const raw = await readFile(FEEDBACK_FILE, "utf-8");
    const lines = raw.trim().split("\n").filter(Boolean);
    const entries = lines
      .map((line) => {
        try {
          return JSON.parse(line) as FeedbackEntry;
        } catch {
          return null;
        }
      })
      .filter(Boolean)
      .reverse(); // newest first

    const total = entries.length;
    const page = entries.slice(offset, offset + limit);

    return NextResponse.json({ entries: page, total });
  } catch (err) {
    console.error("Feedback read error:", err);
    return NextResponse.json({ entries: [], total: 0 });
  }
}