import { usePrisma } from "../utils/prisma";

// ─── Gruppen-Chat ─────────────────────────────────────────────────────────────

export async function getChatMessages(limit = 100) {
  const db = usePrisma();
  return db.chatMessage.findMany({
    where: { roomId: null },
    orderBy: { createdAt: "asc" },
    take: limit,
    select: { id: true, content: true, createdAt: true, userId: true },
  });
}

export async function createChatMessage(userId: string, content: string) {
  const db = usePrisma();
  return db.chatMessage.create({
    data: { userId, content, roomId: null },
    select: { id: true, content: true, createdAt: true, userId: true },
  });
}

// ─── Direktnachrichten ───────────────────────────────────────────────────────

export async function sendDirectMessage(
  senderId: string,
  receiverId: string,
  content: string,
  opts?: {
    replyToId?: string;
    attachmentUrl?: string;
    attachmentType?: string;
    attachmentName?: string;
  },
) {
  const db = usePrisma();
  return db.directMessage.create({
    data: {
      senderId,
      receiverId,
      content,
      replyToId: opts?.replyToId || null,
      attachmentUrl: opts?.attachmentUrl || null,
      attachmentType: opts?.attachmentType || null,
      attachmentName: opts?.attachmentName || null,
    },
    select: {
      id: true,
      content: true,
      createdAt: true,
      replyToId: true,
      attachmentUrl: true,
      attachmentType: true,
      attachmentName: true,
      likesCount: true,
      replyTo: {
        select: { id: true, senderId: true, content: true },
      },
    },
  });
}

export async function getDmHistory(
  userId: string,
  partnerId: string,
  page = 1,
  limit = 50,
) {
  const db = usePrisma();
  const offset = (page - 1) * limit;
  return db.directMessage.findMany({
    where: {
      OR: [
        { senderId: userId, receiverId: partnerId },
        { senderId: partnerId, receiverId: userId },
      ],
    },
    orderBy: { createdAt: "desc" },
    skip: offset,
    take: limit,
    select: {
      id: true,
      senderId: true,
      receiverId: true,
      content: true,
      createdAt: true,
      readAt: true,
      replyToId: true,
      attachmentUrl: true,
      attachmentType: true,
      attachmentName: true,
      likesCount: true,
      replyTo: {
        select: { id: true, senderId: true, content: true },
      },
    },
  });
}

export async function markDmsAsRead(senderId: string, receiverId: string) {
  const db = usePrisma();
  return db.directMessage.updateMany({
    where: { senderId, receiverId, readAt: null },
    data: { readAt: new Date() },
  });
}

export async function getDmConversations(userId: string) {
  const db = usePrisma();
  // Alle DMs als Sender oder Empfänger, neueste zuerst
  return db.directMessage.findMany({
    where: {
      OR: [{ senderId: userId }, { receiverId: userId }],
    },
    orderBy: { createdAt: "desc" },
    take: 500,
    select: {
      id: true,
      senderId: true,
      receiverId: true,
      content: true,
      createdAt: true,
      readAt: true,
    },
  });
}

export async function countUnreadDms(receiverId: string) {
  const db = usePrisma();
  const rows = await db.directMessage.findMany({
    where: { receiverId, readAt: null },
    select: { senderId: true },
  });
  const byPartner: Record<string, number> = {};
  for (const r of rows) {
    byPartner[r.senderId] = (byPartner[r.senderId] ?? 0) + 1;
  }
  return byPartner;
}