import { NextResponse } from "next/server";
import { and, isNotNull, sql } from "drizzle-orm";
import { db } from "@/lib/db";
import { claws } from "@/lib/db/schema";
import { getCacheHeatmap, setCacheHeatmap } from "@/lib/redis";

export async function GET() {
  try {
    const cached = await getCacheHeatmap();
    if (cached) {
      return NextResponse.json(JSON.parse(cached));
    }

    const fiveMinutesAgo = new Date(Date.now() - 5 * 60 * 1000);

    // Query all claws with coordinates, grouped by location
    const locationRows = await db
      .select({
        city: claws.city,
        country: claws.country,
        latitude: claws.latitude,
        longitude: claws.longitude,
        count: sql<number>`count(*)`,
        onlineCount: sql<number>`sum(case when ${claws.lastHeartbeat} >= ${fiveMinutesAgo} then 1 else 0 end)`,
      })
      .from(claws)
      .where(
        and(
          isNotNull(claws.latitude),
          isNotNull(claws.longitude)
        )
      )
      .groupBy(
        claws.city,
        claws.country,
        claws.latitude,
        claws.longitude
      );

    // Fetch individual claw details for all claws with coordinates
    const clawDetails = await db
      .select({
        id: claws.id,
        name: claws.name,
        city: claws.city,
        country: claws.country,
        latitude: claws.latitude,
        longitude: claws.longitude,
        lastHeartbeat: claws.lastHeartbeat,
      })
      .from(claws)
      .where(
        and(
          isNotNull(claws.latitude),
          isNotNull(claws.longitude)
        )
      );

    // Group claw details by location key
    const clawsByLocation = new Map<string, Array<{ id: string; name: string; isOnline: boolean }>>();
    for (const claw of clawDetails) {
      const key = `${claw.latitude}:${claw.longitude}`;
      const isOnline = claw.lastHeartbeat ? claw.lastHeartbeat >= fiveMinutesAgo : false;
      const list = clawsByLocation.get(key) ?? [];
      list.push({ id: claw.id, name: claw.name, isOnline });
      clawsByLocation.set(key, list);
    }

    const points = locationRows.map((row) => {
      const key = `${row.latitude}:${row.longitude}`;
      const clawList = (clawsByLocation.get(key) ?? []).slice(0, 20);
      return {
        lat: Number(row.latitude),
        lng: Number(row.longitude),
        weight: row.count,
        clawCount: row.count,
        onlineCount: Number(row.onlineCount ?? 0),
        city: row.city,
        country: row.country,
        claws: clawList,
      };
    });

    const lastUpdated = new Date().toISOString();
    const responseData = { points, lastUpdated };

    await setCacheHeatmap(JSON.stringify(responseData));

    return NextResponse.json(responseData);
  } catch (error) {
    console.error("Heatmap error:", error);
    return NextResponse.json(
      { error: "Internal server error" },
      { status: 500 }
    );
  }
}