// services/messageService.ts
// Handle encrypted communication between landlords and tenants

import { and, asc, desc, eq, ilike, inArray, or, sql } from "drizzle-orm";
import { db } from "../db/db.ts";
import { Message } from "../db/interfaces.ts";
import { leases, messages, properties, users } from "../db/schema.ts";

export type MessageAttachment = { url: string; name: string; type: string };

// Extended interface for dashboard messages with UI properties
export interface DashboardMessage extends Message {
  sender_name?: string;
  recipient_name?: string;
  property_address?: string;
  created_at?: number | null; // UI-friendly timestamp (maps to created_on)
  time_ago?: string; // Human-readable time difference
  conversation_id?: string; // For grouping messages in conversations
}

export interface MessageQueryOptions {
  page?: number;
  pageSize?: number;
  sort?: "newest" | "oldest";
  status?: "all" | "read" | "unread";
  type?: "all" | "general" | "maintenance" | "payment" | "notice";
  direction?: "all" | "sent" | "received";
  search?: string;
}

export interface MessagePage {
  messages: DashboardMessage[];
  page: number;
  pageSize: number;
  total: number;
  totalMessages: number;
  totalPages: number;
  unread: number;
}

function formatPropertyAddress(
  property: {
    address_1?: string | null;
    address_2?: string | null;
    city?: string | null;
    state?: string | null;
    zip?: string | null;
  } | null,
) {
  if (!property) return "";
  const street = [property.address_1, property.address_2]
    .filter(Boolean)
    .join(" ")
    .trim();
  const cityState = [property.city, property.state]
    .filter(Boolean)
    .join(", ")
    .trim();
  const zip = property.zip?.trim() || "";
  const region = [cityState, zip].filter(Boolean).join(" ").trim();
  return [street, region].filter(Boolean).join(", ").trim();
}

function clampPageSize(value: number) {
  if (Number.isNaN(value) || value <= 0) return 10;
  return Math.min(50, Math.max(5, value));
}

function normalizeOptions(options: MessageQueryOptions) {
  const page = Math.max(1, options.page ?? 1);
  const pageSize = clampPageSize(options.pageSize ?? 10);
  const sort = options.sort === "oldest" ? "oldest" : "newest";
  const status = options.status ?? "all";
  const type = options.type ?? "all";
  const direction = options.direction ?? "all";
  const search = options.search?.trim() || "";
  return { page, pageSize, sort, status, type, direction, search };
}

// Create new message
export async function createMessage(
  lease_id: string | null,
  sender_id: string,
  recipient_id: string,
  message_type: string,
  subject: string,
  content: string,
  parent_message_id: string | null = null,
  attachments: MessageAttachment[] | null = null,
): Promise<Message[]> {
  const attachmentsJson = attachments && attachments.length > 0
    ? JSON.stringify(attachments)
    : null;
  const now = Date.now();
  return await db.insert(messages)
    .values({
      id: crypto.randomUUID(),
      lease_id: lease_id ?? null,
      sender_id,
      recipient_id,
      message_type,
      subject,
      parent_message_id,
      attachments_json: attachmentsJson,
      content,
      content_encrypted: content,
      is_read: false,
      created_on: now,
    })
    .returning() as unknown as Message[];
}

// Get messages for a lease
export async function getMessagesByLease(lease_id: string) {
  return await db.select()
    .from(messages)
    .where(eq(messages.lease_id, lease_id))
    .orderBy(messages.created_on);
}

// Get messages for a user (sent or received)
export async function getMessagesByUser(user_id: string) {
  return await db.select()
    .from(messages)
    .where(or(
      eq(messages.sender_id, user_id),
      eq(messages.recipient_id, user_id),
    ))
    .orderBy(messages.created_on);
}

export async function getMessagesForUser(
  user_id: string,
  options: MessageQueryOptions = {},
): Promise<MessagePage> {
  const { page, pageSize, sort, status, type, direction, search } =
    normalizeOptions(options);

  const directionClause = direction === "sent"
    ? eq(messages.sender_id, user_id)
    : direction === "received"
    ? eq(messages.recipient_id, user_id)
    : or(eq(messages.sender_id, user_id), eq(messages.recipient_id, user_id));

  const clauses = [directionClause];

  if (status === "read") {
    clauses.push(and(
      eq(messages.recipient_id, user_id),
      eq(messages.is_read, true),
    ));
  } else if (status === "unread") {
    clauses.push(and(
      eq(messages.recipient_id, user_id),
      eq(messages.is_read, false),
    ));
  }

  if (type !== "all") {
    clauses.push(eq(messages.message_type, type));
  }

  if (search) {
    const pattern = `%${search}%`;
    clauses.push(or(
      ilike(messages.subject, pattern),
      ilike(messages.content, pattern),
    ));
  }

  const whereClause = clauses.length > 1 ? and(...clauses) : clauses[0];

  const countResult = await db.select({
    count: sql<number>`count(*)`,
  })
    .from(messages)
    .where(whereClause);
  const total = countResult[0]?.count ?? 0;
  const totalPages = Math.max(1, Math.ceil(total / pageSize));
  const unreadResult = await db.select({
    count: sql<number>`count(*)`,
  })
    .from(messages)
    .where(and(
      eq(messages.recipient_id, user_id),
      eq(messages.is_read, false),
    ));
  const unread = unreadResult[0]?.count ?? 0;
  const offset = (page - 1) * pageSize;

  const rawMessages = await db.select()
    .from(messages)
    .where(whereClause)
    .orderBy(
      sort === "oldest" ? asc(messages.created_on) : desc(messages.created_on),
    )
    .limit(pageSize)
    .offset(offset) as unknown as Message[];

  const userIds = Array.from(
    new Set(
      rawMessages.flatMap((message) => [
        message.sender_id,
        message.recipient_id,
      ]).filter(Boolean) as string[],
    ),
  );

  const userMap = new Map<string, { name: string | null }>();
  if (userIds.length > 0) {
    const userRows = await db.select({
      id: users.id,
      name: users.name,
    })
      .from(users)
      .where(inArray(users.id, userIds));
    userRows.forEach((row) => userMap.set(row.id, { name: row.name }));
  }

  const leaseIds = Array.from(
    new Set(
      rawMessages.map((message) => message.lease_id).filter(
        Boolean,
      ) as string[],
    ),
  );

  const leaseMap = new Map<
    string,
    { property_id: string | null; property_address: string | null }
  >();
  if (leaseIds.length > 0) {
    const leaseRows = await db.select({
      id: leases.id,
      property_id: leases.property_id,
      property_address: leases.property_address,
    })
      .from(leases)
      .where(inArray(leases.id, leaseIds));
    leaseRows.forEach((row) =>
      leaseMap.set(row.id, {
        property_id: row.property_id,
        property_address: row.property_address,
      })
    );
  }

  const propertyIds = Array.from(
    new Set(
      Array.from(leaseMap.values())
        .map((lease) => lease.property_id)
        .filter(Boolean) as string[],
    ),
  );
  const propertyMap = new Map<string, string>();
  if (propertyIds.length > 0) {
    const propertyRows = await db.select({
      id: properties.id,
      address_1: properties.address_1,
      address_2: properties.address_2,
      city: properties.city,
      state: properties.state,
      zip: properties.zip,
    })
      .from(properties)
      .where(inArray(properties.id, propertyIds));
    propertyRows.forEach((property) =>
      propertyMap.set(property.id, formatPropertyAddress(property))
    );
  }

  const messagesList: DashboardMessage[] = rawMessages.map((message) => {
    const sender = message.sender_id ? userMap.get(message.sender_id) : null;
    const recipient = message.recipient_id
      ? userMap.get(message.recipient_id)
      : null;
    const lease = message.lease_id ? leaseMap.get(message.lease_id) : null;
    const propertyAddress = lease?.property_address ||
      (lease?.property_id ? propertyMap.get(lease.property_id) : "") ||
      "";

    return {
      ...message,
      sender_name: sender?.name || "Tenant",
      recipient_name: recipient?.name || "Recipient",
      property_address: propertyAddress,
      created_at: message.created_on ?? null,
    };
  });

  return {
    messages: messagesList,
    page,
    pageSize,
    total,
    totalMessages: total,
    totalPages,
    unread,
  };
}

// Get unread messages for a user
export async function getUnreadMessages(user_id: string) {
  return await db.select()
    .from(messages)
    .where(and(
      eq(messages.recipient_id, user_id),
      eq(messages.is_read, false),
    ))
    .orderBy(messages.created_on);
}

// Get messages between two users for a specific lease
export async function getConversation(
  lease_id: string,
  user1_id: string,
  user2_id: string,
) {
  return await db.select()
    .from(messages)
    .where(and(
      eq(messages.lease_id, lease_id),
      or(
        and(
          eq(messages.sender_id, user1_id),
          eq(messages.recipient_id, user2_id),
        ),
        and(
          eq(messages.sender_id, user2_id),
          eq(messages.recipient_id, user1_id),
        ),
      ),
    ))
    .orderBy(messages.created_on);
}

// Mark message as read
export async function markMessageAsRead(id: string) {
  return await db.update(messages)
    .set({ is_read: true })
    .where(eq(messages.id, id))
    .returning();
}

export async function markMessageAsReadForUser(
  id: string,
  user_id: string,
) {
  return await db.update(messages)
    .set({ is_read: true })
    .where(and(eq(messages.id, id), eq(messages.recipient_id, user_id)))
    .returning();
}

// Mark all messages as read for a user
export async function markAllMessagesAsRead(user_id: string) {
  return await db.update(messages)
    .set({ is_read: true })
    .where(and(
      eq(messages.recipient_id, user_id),
      eq(messages.is_read, false),
    ))
    .returning();
}

// Get message by ID
export async function getMessageById(id: string): Promise<Message | null> {
  const result = await db.select()
    .from(messages)
    .where(eq(messages.id, id));
  return (result[0] as unknown as Message | undefined) ?? null;
}

// Get a message thread (root message and all replies)
export async function getMessageThread(
  id: string,
): Promise<Message[] | null> {
  const initialMessage = await getMessageById(id);
  if (!initialMessage) return null;

  // Determine the root message ID. If the message has a parent, we use the parent's ID
  // as the root for the thread query. Otherwise, the message itself is the root.
  const rootId = initialMessage.parent_message_id || id;

  const threadMessages = await db.select()
    .from(messages)
    .where(or(
      eq(messages.id, rootId),
      eq(messages.parent_message_id, rootId),
    ))
    .orderBy(asc(messages.created_on)) as unknown as Message[];

  return threadMessages;
}

// Delete message
export async function deleteMessage(id: string): Promise<Message[]> {
  return await db.delete(messages)
    .where(eq(messages.id, id))
    .returning() as unknown as Message[];
}

export async function deleteMessagesForUser(user_id: string, ids: string[]) {
  const normalizedIds = Array.from(new Set(ids)).filter(Boolean);
  if (normalizedIds.length === 0) return [];

  return await db.delete(messages)
    .where(and(
      inArray(messages.id, normalizedIds),
      or(eq(messages.sender_id, user_id), eq(messages.recipient_id, user_id)),
    ))
    .returning();
}

// Mark multiple messages as read
export async function markMessagesAsRead(user_id: string, ids: string[]) {
  const normalizedIds = Array.from(new Set(ids)).filter(Boolean);
  if (normalizedIds.length === 0) return [];
  return await db.update(messages)
    .set({ is_read: true })
    .where(and(
      eq(messages.recipient_id, user_id),
      inArray(messages.id, normalizedIds),
    ))
    .returning();
}

// Get message count by type for a lease
export async function getMessageStatsByLease(lease_id: string) {
  const allMessages = await getMessagesByLease(lease_id);

  return {
    total: allMessages.length,
    general: allMessages.filter((m) => m.message_type === "general").length,
    maintenance:
      allMessages.filter((m) => m.message_type === "maintenance").length,
    payment: allMessages.filter((m) => m.message_type === "payment").length,
    notice: allMessages.filter((m) => m.message_type === "notice").length,
    unread: allMessages.filter((m) => !m.is_read).length,
  };
}

// Get unread count for a user
export async function getUnreadCount(user_id: string) {
  const unreadMessages = await getUnreadMessages(user_id);
  return unreadMessages.length;
}