// app/api/devices/[id]/history/route.ts
import { NextResponse } from 'next/server';
import { prisma } from '@/lib/prisma';

type RouteParams = { id: string };
type RouteContext = { params: Promise<RouteParams> };

export async function GET(_req: Request, ctx: RouteContext) {
  const { id } = await ctx.params;

  if (!id) {
    return NextResponse.json({ error: 'MISSING_ID' }, { status: 400 });
  }

  try {
    const history = await prisma.deviceHistory.findMany({
      where: { deviceId: id },
      orderBy: { changedAt: 'desc' },
      include: {
        changedBy: true, // 👈 User-Relation laden
      },
    });

    const result = history.map((entry) => {
      const user = entry.changedBy;

      // 👇 Anzeigename nach deiner neuen Logik:
      // arbeitsname > "Vorname Nachname" > nwkennung > email
      const changedByName =
        user?.arbeitsname ??
        (user?.firstName && user?.lastName
          ? `${user.firstName} ${user.lastName}`
          : user?.nwkennung ?? user?.email ?? null);

      // snapshot.changes aus dem JSON holen (bei CREATED evtl. leer)
      let changes: {
        field: string;
        from: string | null;
        to: string | null;
      }[] = [];

      const snapshot = entry.snapshot as any;
      if (snapshot && Array.isArray(snapshot.changes)) {
        changes = snapshot.changes.map((c: any) => ({
          field: String(c.field),
          from: c.before ?? null,
          to: c.after ?? null,
        }));
      }

      return {
        id: entry.id,
        changeType: entry.changeType,
        changedAt: entry.changedAt.toISOString(),
        changedBy: changedByName, // 👈 jetzt schön formatiert
        changes,
      };
    });

    return NextResponse.json(result);
  } catch (err) {
    console.error('[GET /api/devices/[id]/history]', err);
    return NextResponse.json(
      { error: 'INTERNAL_ERROR' },
      { status: 500 },
    );
  }
}