import { NextRequest, NextResponse } from 'next/server';
import { db } from '@/lib/db';
import { getCookieToken, getSessionUser } from '@/lib/auth';
import { invoiceIdSchema } from '@/lib/validation';
import { logActivity } from '@/lib/activity';

type FilterValue = 'all' | 'done' | 'review' | 'duplicates';

// ─── GET: List Invoices ───────────────────────────────────────────────────────

export async function GET(request: NextRequest) {
  try {
    const token = getCookieToken(request);
    if (!token) {
      return NextResponse.json({ error: 'Not authenticated' }, { status: 401 });
    }
    const user = await getSessionUser(token);
    if (!user) {
      return NextResponse.json({ error: 'Not authenticated' }, { status: 401 });
    }

    const { searchParams } = new URL(request.url);
    const filter = (searchParams.get('filter') || 'all') as FilterValue;

    // Build the where clause
    const where: Record<string, unknown> = { userId: user.id };

    switch (filter) {
      case 'done':
        where.status = 'done';
        where.isDuplicate = false;
        break;
      case 'review':
        where.status = 'review';
        break;
      case 'duplicates':
        where.isDuplicate = true;
        break;
      // 'all' uses the base where (userId only)
    }

    const invoices = await db.invoice.findMany({
      where,
      orderBy: { createdAt: 'desc' },
    });

    return NextResponse.json({ invoices });
  } catch (error) {
    console.error('[INVOICES_GET_ERROR]', error);
    return NextResponse.json(
      { error: 'Internal server error' },
      { status: 500 }
    );
  }
}

// ─── DELETE: Remove Invoice ────────────────────────────────────────────────────

export async function DELETE(request: NextRequest) {
  try {
    const token = getCookieToken(request);
    if (!token) {
      return NextResponse.json({ error: 'Not authenticated' }, { status: 401 });
    }
    const user = await getSessionUser(token);
    if (!user) {
      return NextResponse.json({ error: 'Not authenticated' }, { status: 401 });
    }

    const body = await request.json();
    const parsed = invoiceIdSchema.safeParse(body);
    if (!parsed.success) {
      return NextResponse.json(
        { error: parsed.error.issues[0].message },
        { status: 400 }
      );
    }

    // Verify ownership
    const invoice = await db.invoice.findUnique({
      where: { id: parsed.data.id },
    });

    if (!invoice || invoice.userId !== user.id) {
      return NextResponse.json(
        { error: 'Invoice not found' },
        { status: 404 }
      );
    }

    await db.invoice.delete({ where: { id: parsed.data.id } });

    logActivity(user.id, 'delete', 'Invoice deleted', `Removed invoice ${parsed.data.id}`);

    return NextResponse.json({ success: true });
  } catch (error) {
    console.error('[INVOICES_DELETE_ERROR]', error);
    return NextResponse.json(
      { error: 'Internal server error' },
      { status: 500 }
    );
  }
}