/**
 * GET  /api/geoportal/monitor — tile infrastructure status
 * POST /api/geoportal/monitor — trigger actions (rebuild, warm-cache)
 */
import { NextRequest, NextResponse } from "next/server";

export const runtime = "nodejs";
export const dynamic = "force-dynamic";

const TILE_CACHE_INTERNAL = "http://tile-cache:80";
const MARTIN_INTERNAL = "http://martin:3000";
const PMTILES_URL = process.env.NEXT_PUBLIC_PMTILES_URL || "";
const N8N_WEBHOOK_URL = process.env.N8N_WEBHOOK_URL || "";

type NginxStatus = {
  activeConnections: number;
  accepts: number;
  handled: number;
  requests: number;
  reading: number;
  writing: number;
  waiting: number;
};

function parseNginxStatus(text: string): NginxStatus {
  const lines = text.trim().split("\n");
  const active = parseInt(lines[0]?.match(/\d+/)?.[0] ?? "0", 10);
  const counts = lines[2]?.trim().split(/\s+/).map(Number) ?? [0, 0, 0];
  const rw = lines[3]?.match(/\d+/g)?.map(Number) ?? [0, 0, 0];
  return {
    activeConnections: active,
    accepts: counts[0] ?? 0,
    handled: counts[1] ?? 0,
    requests: counts[2] ?? 0,
    reading: rw[0] ?? 0,
    writing: rw[1] ?? 0,
    waiting: rw[2] ?? 0,
  };
}

async function fetchWithTimeout(url: string, timeoutMs = 5000): Promise<Response> {
  const controller = new AbortController();
  const timer = setTimeout(() => controller.abort(), timeoutMs);
  try {
    return await fetch(url, { signal: controller.signal, cache: "no-store" });
  } finally {
    clearTimeout(timer);
  }
}

// Sample tile coordinates for cache testing (Romania, z8)
const SAMPLE_TILES = [
  { z: 8, x: 143, y: 91, source: "gis_uats_z8" },
  { z: 14, x: 9205, y: 5965, source: "gis_terenuri" },
];

export async function GET() {
  const result: Record<string, unknown> = {
    timestamp: new Date().toISOString(),
  };

  // 1. Nginx status
  try {
    const res = await fetchWithTimeout(`${TILE_CACHE_INTERNAL}/status`);
    if (res.ok) {
      result.nginx = parseNginxStatus(await res.text());
    } else {
      result.nginx = { error: `HTTP ${res.status}` };
    }
  } catch {
    result.nginx = { error: "tile-cache unreachable" };
  }

  // 2. Martin catalog
  try {
    const res = await fetchWithTimeout(`${MARTIN_INTERNAL}/catalog`);
    if (res.ok) {
      const catalog = await res.json() as { tiles?: Record<string, unknown> };
      const sources = Object.keys(catalog.tiles ?? {});
      result.martin = { status: "ok", sources, sourceCount: sources.length };
    } else {
      result.martin = { error: `HTTP ${res.status}` };
    }
  } catch {
    result.martin = { error: "martin unreachable" };
  }

  // 3. PMTiles info
  if (PMTILES_URL) {
    try {
      const res = await fetchWithTimeout(PMTILES_URL, 3000);
      result.pmtiles = {
        url: PMTILES_URL,
        status: res.ok ? "ok" : `HTTP ${res.status}`,
        size: res.headers.get("content-length")
          ? `${(parseInt(res.headers.get("content-length") ?? "0", 10) / 1024 / 1024).toFixed(1)} MB`
          : "unknown",
        lastModified: res.headers.get("last-modified") ?? "unknown",
      };
    } catch {
      result.pmtiles = { url: PMTILES_URL, error: "unreachable" };
    }
  } else {
    result.pmtiles = { status: "not configured" };
  }

  // 4. Cache test — request sample tiles and check X-Cache-Status
  const cacheTests: Record<string, string>[] = [];
  for (const tile of SAMPLE_TILES) {
    try {
      const url = `${TILE_CACHE_INTERNAL}/${tile.source}/${tile.z}/${tile.x}/${tile.y}`;
      const res = await fetchWithTimeout(url, 10000);
      cacheTests.push({
        tile: `${tile.source}/${tile.z}/${tile.x}/${tile.y}`,
        status: `${res.status}`,
        cache: res.headers.get("x-cache-status") ?? "unknown",
      });
    } catch {
      cacheTests.push({
        tile: `${tile.source}/${tile.z}/${tile.x}/${tile.y}`,
        status: "error",
        cache: "unreachable",
      });
    }
  }
  result.cacheTests = cacheTests;

  // 5. Config summary
  result.config = {
    martinUrl: process.env.NEXT_PUBLIC_MARTIN_URL ?? "(not set)",
    pmtilesUrl: PMTILES_URL || "(not set)",
    n8nWebhook: N8N_WEBHOOK_URL ? "configured" : "not set",
  };

  return NextResponse.json(result);
}

export async function POST(request: NextRequest) {
  const body = await request.json() as { action?: string };
  const action = body.action;

  if (action === "rebuild") {
    if (!N8N_WEBHOOK_URL) {
      return NextResponse.json({ error: "N8N_WEBHOOK_URL not configured" }, { status: 400 });
    }
    try {
      await fetch(N8N_WEBHOOK_URL, {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({
          event: "manual-rebuild",
          timestamp: new Date().toISOString(),
        }),
      });
      return NextResponse.json({ ok: true, message: "Rebuild triggered via N8N" });
    } catch (err) {
      const msg = err instanceof Error ? err.message : String(err);
      return NextResponse.json({ error: `Webhook failed: ${msg}` }, { status: 500 });
    }
  }

  if (action === "warm-cache") {
    // Warm cache from within the container (tile-cache is on same Docker network)
    const sources = ["gis_terenuri", "gis_cladiri"];
    let warmed = 0;
    const promises: Promise<void>[] = [];
    for (const source of sources) {
      // Bucharest area z14
      for (let x = 9200; x <= 9210; x++) {
        for (let y = 5960; y <= 5970; y++) {
          promises.push(
            fetchWithTimeout(`${TILE_CACHE_INTERNAL}/${source}/14/${x}/${y}`, 30000)
              .then(() => { warmed++; })
              .catch(() => { /* noop */ }),
          );
        }
      }
    }
    await Promise.all(promises);
    return NextResponse.json({ ok: true, message: `Cache warmed: ${warmed} tiles` });
  }

  return NextResponse.json({ error: "Unknown action" }, { status: 400 });
}