// app/api/devices/route.ts
import { NextResponse } from 'next/server';
import { prisma } from '@/lib/prisma';
import type { Prisma } from '@/generated/prisma/client';
import { getCurrentUserId } from '@/lib/auth';
import type { Server as IOServer } from 'socket.io';

export async function GET() {
  try {
    const devices = await prisma.device.findMany({
      include: {
        group: true,
        location: true,
        tags: true,
        parentDevice: true,
        accessories: true,
      },
      orderBy: { inventoryNumber: 'asc' },
    });

    return NextResponse.json(
      devices.map((d) => ({
        inventoryNumber: d.inventoryNumber,
        name: d.name,
        manufacturer: d.manufacturer,
        model: d.model,
        serialNumber: d.serialNumber,
        productNumber: d.productNumber,
        comment: d.comment,
        ipv4Address: d.ipv4Address,
        ipv6Address: d.ipv6Address,
        macAddress: d.macAddress,
        username: d.username,
        passwordHash: d.passwordHash,
        group: d.group?.name ?? null,
        location: d.location?.name ?? null,
        tags: d.tags.map((t) => t.name),
        loanedTo: d.loanedTo,
        loanedFrom: d.loanedFrom
          ? d.loanedFrom.toISOString()
          : null,
        loanedUntil: d.loanedUntil
          ? d.loanedUntil.toISOString()
          : null,
        loanComment: d.loanComment,
        createdAt: d.createdAt.toISOString(),
        updatedAt: d.updatedAt.toISOString(),

        // 🔹 wichtig für dein Dropdown:
        parentInventoryNumber: d.parentDeviceId,          // Hauptgerät-Nummer oder null
        parentName: d.parentDevice?.name ?? null,
        accessories: d.accessories.map((a) => ({
          inventoryNumber: a.inventoryNumber,
          name: a.name,
        })),
      })),
    );
  } catch (err) {
    console.error('[GET /api/devices]', err);
    return NextResponse.json(
      { error: 'INTERNAL_ERROR' },
      { status: 500 },
    );
  }
}

export async function POST(req: Request) {
  try {
    const body = await req.json();

    const {
      inventoryNumber,
      name,
      manufacturer,
      model,
      serialNumber,
      productNumber,
      comment,
      group,
      location,
      ipv4Address,
      ipv6Address,
      macAddress,
      username,
      passwordHash,
      tags,
      loanedTo,
      loanedFrom,
      loanedUntil,
      loanComment,
      parentInventoryNumber,
    } = body;

    if (!inventoryNumber || !name) {
      return NextResponse.json(
        { error: 'inventoryNumber und name sind Pflichtfelder.' },
        { status: 400 },
      );
    }

    const existing = await prisma.device.findUnique({
      where: { inventoryNumber },
    });
    if (existing) {
      return NextResponse.json(
        { error: 'Gerät mit dieser Inventar-Nr. existiert bereits.' },
        { status: 409 },
      );
    }

    const userId = await getCurrentUserId();
    let canConnectUser = false;

    if (userId) {
      const user = await prisma.user.findUnique({
        where: { nwkennung: userId },
        select: { nwkennung: true },
      });
      if (user) {
        canConnectUser = true;
      } else {
        console.warn(
          `[POST /api/devices] User mit id=${userId} nicht gefunden – createdBy/changedBy werden nicht gesetzt.`,
        );
      }
    }

    // Gruppe
    let groupId: string | null = null;
    if (group && typeof group === 'string' && group.trim() !== '') {
      const grp = await prisma.deviceGroup.upsert({
        where: { name: group.trim() },
        update: {},
        create: { name: group.trim() },
      });
      groupId = grp.id;
    }

    // Standort
    let locationId: string | null = null;
    if (location && typeof location === 'string' && location.trim() !== '') {
      const loc = await prisma.location.upsert({
        where: { name: location.trim() },
        update: {},
        create: { name: location.trim() },
      });
      locationId = loc.id;
    }

    const tagNames: string[] = Array.isArray(tags)
      ? tags.map((t: unknown) => String(t).trim()).filter(Boolean)
      : [];

    // 🔹 NEU: Hauptgerät-Relation (optional)
    let parentDeviceRelation:
      Prisma.DeviceCreateInput['parentDevice'] | undefined;

    if (
      parentInventoryNumber &&
      typeof parentInventoryNumber === 'string' &&
      parentInventoryNumber.trim() !== ''
    ) {
      const trimmed = parentInventoryNumber.trim();

      // sich selbst als Hauptgerät → Fehler
      if (trimmed === inventoryNumber) {
        return NextResponse.json(
          {
            error:
              'Ein Gerät kann nicht gleichzeitig sein eigenes Hauptgerät sein.',
          },
          { status: 400 },
        );
      }

      const parent = await prisma.device.findUnique({
        where: { inventoryNumber: trimmed },
        select: { inventoryNumber: true },
      });

      if (!parent) {
        return NextResponse.json(
          {
            error: `Hauptgerät mit Inventar-Nr. ${trimmed} wurde nicht gefunden.`,
          },
          { status: 400 },
        );
      }

      parentDeviceRelation = {
        connect: { inventoryNumber: trimmed },
      };
    }

    const created = await prisma.device.create({
      data: {
        inventoryNumber,
        name,
        manufacturer,
        model,
        serialNumber: serialNumber ?? null,
        productNumber: productNumber ?? null,
        comment: comment ?? null,
        ipv4Address: ipv4Address ?? null,
        ipv6Address: ipv6Address ?? null,
        macAddress: macAddress ?? null,
        username: username ?? null,
        passwordHash: passwordHash ?? null,

        // Verleih-Felder
        loanedTo: loanedTo ?? null,
        loanedFrom: loanedFrom ? new Date(loanedFrom) : null,
        loanedUntil: loanedUntil ? new Date(loanedUntil) : null,
        loanComment: loanComment ?? null,

        // 🔹 optionales Hauptgerät
        ...(parentDeviceRelation
          ? { parentDevice: parentDeviceRelation }
          : {}),

        ...(groupId
          ? {
              group: {
                connect: { id: groupId },
              },
            }
          : {}),

        ...(locationId
          ? {
              location: {
                connect: { id: locationId },
              },
            }
          : {}),

        // 🔹 FIX: User via nwkennung verbinden
        ...(canConnectUser && userId
          ? {
              createdBy: {
                connect: { nwkennung: userId },
              },
            }
          : {}),

        ...(tagNames.length
          ? {
              tags: {
                connectOrCreate: tagNames.map((name) => ({
                  where: { name },
                  create: { name },
                })),
              },
            }
          : {}),
      },
      include: {
        group: true,
        location: true,
        tags: true,
        // 🔹 NEU: parentDevice für Antwort/Event
        parentDevice: {
          select: { inventoryNumber: true, name: true },
        },
      },
    });

    const snapshot: Prisma.JsonObject = {
      before: null,
      after: {
        inventoryNumber: created.inventoryNumber,
        name: created.name,
        manufacturer: created.manufacturer,
        model: created.model,
        serialNumber: created.serialNumber,
        productNumber: created.productNumber,
        comment: created.comment,
        ipv4Address: created.ipv4Address,
        ipv6Address: created.ipv6Address,
        macAddress: created.macAddress,
        username: created.username,
        passwordHash: created.passwordHash,
        group: created.group?.name ?? null,
        location: created.location?.name ?? null,
        tags: created.tags.map((t) => t.name),
        loanedTo: created.loanedTo,
        loanedFrom: created.loanedFrom
          ? created.loanedFrom.toISOString()
          : null,
        loanedUntil: created.loanedUntil
          ? created.loanedUntil.toISOString()
          : null,
        loanComment: created.loanComment,
        // 🔹 NEU
        parentInventoryNumber: created.parentDeviceId,
        parentName: created.parentDevice?.name ?? null,
        createdAt: created.createdAt.toISOString(),
        updatedAt: created.updatedAt.toISOString(),
      },
      changes: [],
    };

    await prisma.deviceHistory.create({
      data: {
        deviceId: created.inventoryNumber,
        changeType: 'CREATED',
        snapshot,
        changedById: canConnectUser && userId ? userId : null,
      },
    });

    const io = (global as any).devicesIo as IOServer | undefined;
    if (io) {
      io.emit('device:created', {
        inventoryNumber: created.inventoryNumber,
        name: created.name,
        manufacturer: created.manufacturer,
        model: created.model,
        serialNumber: created.serialNumber,
        productNumber: created.productNumber,
        comment: created.comment,
        ipv4Address: created.ipv4Address,
        ipv6Address: created.ipv6Address,
        macAddress: created.macAddress,
        username: created.username,
        group: created.group?.name ?? null,
        location: created.location?.name ?? null,
        tags: created.tags.map((t) => t.name),
        loanedTo: created.loanedTo,
        loanedFrom: created.loanedFrom
          ? created.loanedFrom.toISOString()
          : null,
        loanedUntil: created.loanedUntil
          ? created.loanedUntil.toISOString()
          : null,
        loanComment: created.loanComment,
        updatedAt: created.updatedAt.toISOString(),
      });
    }

    return NextResponse.json(
    {
      inventoryNumber: created.inventoryNumber,
      name: created.name,
      manufacturer: created.manufacturer,
      model: created.model,
      serialNumber: created.serialNumber,
      productNumber: created.productNumber,
      comment: created.comment,
      ipv4Address: created.ipv4Address,
      ipv6Address: created.ipv6Address,
      macAddress: created.macAddress,
      username: created.username,
      passwordHash: created.passwordHash,
      group: created.group?.name ?? null,
      location: created.location?.name ?? null,
      tags: created.tags.map((t) => t.name),
      loanedTo: created.loanedTo,
      loanedFrom: created.loanedFrom
        ? created.loanedFrom.toISOString()
        : null,
      loanedUntil: created.loanedUntil
        ? created.loanedUntil.toISOString()
        : null,
      loanComment: created.loanComment,
      // 🔹 NEU
      parentInventoryNumber: created.parentDeviceId,
      parentName: created.parentDevice?.name ?? null,
      updatedAt: created.updatedAt.toISOString(),
    },
    { status: 201 },
  );
  } catch (err) {
    console.error('[POST /api/devices]', err);
    return NextResponse.json(
      { error: 'Interner Serverfehler beim Anlegen des Geräts.' },
      { status: 500 },
    );
  }
}