'use server';

import { sessionUser } from '@/auth';
import prisma from './prisma';
import { ChatWithMessages, MessageRaw } from './types';
import { revalidatePath } from 'next/cache';

/**
 * Finds or creates a user in the database based on the provided email and name.
 * If the user already exists, it returns the existing user.
 * If the user doesn't exist, it creates a new user and returns it.
 *
 * @param email - The email of the user.
 * @param name - The name of the user.
 * @returns A promise that resolves to the user object.
 */
export async function dbFindOrCreateUser(email: string, name: string) {
  // Try to find the user by email
  const user = await prisma.user.findUnique({
    where: { email: email },
  });

  // If the user doesn't exist, create it
  if (user) {
    return user;
  } else {
    return prisma.user.create({
      data: {
        email: email,
        name: name,
      },
    });
  }
}

/**
 * Retrieves all chats with their associated messages for the current user.
 * @returns A promise that resolves to an array of `ChatWithMessages` objects.
 */
export async function dbGetAllChat(): Promise<ChatWithMessages[]> {
  const { id: userId } = await sessionUser();

  if (!userId) return [];

  return prisma.chat.findMany({
    where: { userId },
    include: {
      messages: true,
    },
  });
}

/**
 * Retrieves a chat with messages from the database based on the provided ID.
 * @param id - The ID of the chat to retrieve.
 * @returns A Promise that resolves to a ChatWithMessages object if found, or null if not found.
 */
export async function dbGetChat(id: string): Promise<ChatWithMessages | null> {
  return prisma.chat.findUnique({
    where: { id },
    include: {
      messages: true,
    },
  });
}

/**
 * Creates a new chat in the database.
 *
 * @param {string} options.id - The ID of the chat (optional).
 * @param {string} options.mediaUrl - The media URL for the chat.
 * @param {MessageRaw[]} options.initMessages - The initial messages for the chat (optional).
 * @returns {Promise<Chat>} The created chat object.
 */
export async function dbPostCreateChat({
  id,
  mediaUrl,
  initMessages = [],
}: {
  id?: string;
  mediaUrl: string;
  initMessages?: MessageRaw[];
}) {
  const { id: userId } = await sessionUser();
  const userConnect = userId
    ? {
        user: {
          connect: { id: userId }, // Connect the chat to an existing user
        },
      }
    : {};
  try {
    const response = await prisma.chat.create({
      data: {
        id,
        mediaUrl: mediaUrl,
        ...userConnect,
        messages: {
          create: initMessages.map(message => ({
            ...message,
            ...userConnect,
          })),
        },
      },
      include: {
        messages: true,
      },
    });

    revalidatePath('/chat', 'layout');
    return response;
  } catch (error) {
    console.error(error);
  }
}

/**
 * Creates a new message in the database.
 * @param chatId - The ID of the chat where the message belongs.
 * @param message - The message object to be created.
 * @returns A promise that resolves to the created message.
 */
export async function dbPostCreateMessage(chatId: string, message: MessageRaw) {
  const { id: userId } = await sessionUser();
  const userConnect = userId
    ? {
        user: {
          connect: { id: userId }, // Connect the chat to an existing user
        },
      }
    : {};

  return prisma.message.create({
    data: {
      content: message.content,
      role: message.role,
      chat: {
        connect: { id: chatId },
      },
      ...userConnect,
    },
  });
}

export async function dbDeleteChat(chatId: string) {
  await prisma.chat.delete({
    where: { id: chatId },
  });

  revalidatePath('/chat', 'layout');

  return;
}