import express from "express";
import { User } from "../models/User.js";

const router = express.Router();

router.get("/:field", async (req, res) => {
  const { field } = req.params;
  const lat = parseFloat(req.query.lat);
  const lon = parseFloat(req.query.lon);
  if (isNaN(lat) || isNaN(lon)) {
    return res.status(400).json({ error: "Must provide lat & lon" });
  }

  const rawRadius = parseFloat(req.query.radius);
  const radiusKm = isNaN(rawRadius) || rawRadius < 0 ? 50 : rawRadius;
  const maxDistance = radiusKm * 1000;
  const page = Math.max(1, parseInt(req.query.page) || 1);
  const limit = 6; // now 6 per page
  const skip = (page - 1) * limit;

  const sortBy = req.query.sortBy === "rate" ? "rate" : "distance";
  const order = req.query.order === "desc" ? -1 : 1;

  try {
    // pipeline to get paged docs
    const pipeline = [
      {
        $geoNear: {
          near: { type: "Point", coordinates: [lon, lat] },
          distanceField: "distanceMeters",
          maxDistance,
          spherical: true,
        },
      },
      {
        $match: {
          "profile.field": field,
          "profile.published": true,
        },
      },
      {
        $sort:
          sortBy === "rate"
            ? { "profile.rate": order }
            : { distanceMeters: order },
      },
      { $skip: skip },
      { $limit: limit },
    ];

    // pipeline to count total matching
    const countPipeline = [
      {
        $geoNear: {
          near: { type: "Point", coordinates: [lon, lat] },
          distanceField: "distanceMeters",
          maxDistance,
          spherical: true,
        },
      },
      {
        $match: {
          "profile.field": field,
          "profile.published": true,
        },
      },
      { $count: "count" },
    ];

    const [docs, countRes] = await Promise.all([
      User.aggregate(pipeline),
      User.aggregate(countPipeline),
    ]);

    const total = countRes[0]?.count || 0;
    const totalPages = Math.ceil(total / limit);

    const pros = docs.map((u) => ({
      _id: u._id,
      profile: u.profile,
      distanceKm: u.distanceMeters / 1000,
    }));

    return res.json({ pros, page, totalPages });
  } catch (err) {
    return res.status(500).json({ error: err.message });
  }
});

export default router;