import { ListObjectsV2Command, PutObjectCommand, S3Client } from "@aws-sdk/client-s3";
import type { SupabaseClient } from "@supabase/supabase-js";
import type { Context, Next } from "hono";
import type { EventAndTablo } from "./types.ts";

export const generateICSFromEvents = (
  events: EventAndTablo[],
  calendarName: string = "Planning"
) => {
  const formatDate = (date: string, time: string) => {
    // Combine date (YYYY-MM-DD) and time (HH:MM:SS) into ISO format then convert to UTC
    const dateTime = new Date(`${date}T${time}`);
    return `${dateTime.toISOString().replace(/[-:]/g, "").split(".")[0]}Z`;
  };

  const escapeICSText = (text: string) => {
    return text
      .replace(/\\/g, "\\\\")
      .replace(/;/g, "\\;")
      .replace(/,/g, "\\,")
      .replace(/\n/g, "\\n")
      .replace(/\r/g, "");
  };

  const generateUID = (eventId: string) => {
    return `${eventId}@xtablo.com`;
  };

  let icsContent = [
    "BEGIN:VCALENDAR",
    "VERSION:2.0",
    "PRODID:-//XTablo//Planning Export//EN",
    `X-WR-CALNAME:${escapeICSText(calendarName)}`,
    "X-WR-TIMEZONE:Europe/Paris",
    "CALSCALE:GREGORIAN",
    "METHOD:PUBLISH",
  ].join("\r\n");

  events.forEach((event) => {
    if (!event.start_date || !event.start_time || !event.title) return;

    const startDateTime = formatDate(event.start_date, event.start_time);
    const endDateTime = event.end_time
      ? formatDate(event.start_date, event.end_time)
      : formatDate(event.start_date, event.start_time); // Default to start time if no end time

    const eventLines = [
      "",
      "BEGIN:VEVENT",
      `UID:${generateUID(event.event_id)}`,
      `DTSTART:${startDateTime}`,
      `DTEND:${endDateTime}`,
      `SUMMARY:${escapeICSText(event.title)}`,
      `DESCRIPTION:${escapeICSText(`Tablo: ${event.tablo_name}\n${event.description || ""}`)}`,
      event.tablo_name ? `CATEGORIES:${escapeICSText(event.tablo_name)}` : "",
      `CREATED:${new Date().toISOString().replace(/[-:]/g, "").split(".")[0]}Z`,
      `LAST-MODIFIED:${new Date().toISOString().replace(/[-:]/g, "").split(".")[0]}Z`,
      "STATUS:CONFIRMED",
      "TRANSP:OPAQUE",
      "END:VEVENT",
    ].filter((line) => line !== ""); // Remove empty lines

    icsContent += `\r\n${eventLines.join("\r\n")}`;
  });

  icsContent += "\r\nEND:VCALENDAR";

  return icsContent;
};

export const writeCalendarFileToR2 = async (
  s3_client: S3Client,
  supabase: SupabaseClient,
  inputs: {
    token: string;
    tabloName: string;
    tablo_id: string;
  }
) => {
  const { token, tabloName, tablo_id } = inputs;

  const bucketName = "calendars";

  const key = `${token}/${tabloName}.ics`;

  const { data: events, error: eventsError } = await supabase
    .from("events_and_tablos")
    .select("*")
    .eq("tablo_id", tablo_id);

  if (eventsError || !events) {
    throw new Error("Failed to generate events");
  }

  const eventsData = events as EventAndTablo[];

  const icsContent = generateICSFromEvents(eventsData, tabloName);

  await s3_client.send(
    new PutObjectCommand({
      Bucket: bucketName,
      Key: key,
      Body: icsContent,
    })
  );
};

export const getTabloFileNames = async (s3_client: S3Client, tabloId: string) => {
  const bucketName = "tablo-data";

  const { Contents } = await s3_client.send(
    new ListObjectsV2Command({
      Bucket: bucketName,
      Prefix: tabloId,
    })
  );

  return Contents?.map((content) => content.Key?.split("/")[1]).filter(
    (content) => content?.length && content.length > 0
  );
};

const isTabloMember = async (supabase: SupabaseClient, tabloId: string, userId: string) => {
  const { data: tabloAccess, error: isMemberError } = await supabase
    .from("tablo_access")
    .select("*")
    .eq("tablo_id", tabloId)
    .eq("user_id", userId)
    .eq("is_active", true);

  if (isMemberError) {
    return false;
  }

  return tabloAccess?.length > 0;
};

const isTabloAdmin = async (supabase: SupabaseClient, tabloId: string, userId: string) => {
  const { data: tabloAccess, error: isAdminError } = await supabase
    .from("tablo_access")
    .select("*")
    .eq("tablo_id", tabloId)
    .eq("user_id", userId)
    .eq("is_active", true)
    .eq("is_admin", true);

  if (isAdminError) {
    return false;
  }

  return tabloAccess?.length > 0;
};

export const checkTabloMember = async (c: Context, next: Next) => {
  const supabase = c.get("supabase");
  const user = c.get("user");
  const tabloId = c.req.param("tabloId");
  const isMember = await isTabloMember(supabase, tabloId, user.id);
  if (!isMember) {
    return c.json({ error: "You are not a member of this tablo" }, 403);
  }
  await next();
};

export const checkTabloAdmin = async (c: Context, next: Next) => {
  const supabase = c.get("supabase");
  const user = c.get("user");
  const tabloId = c.req.param("tabloId") || c.req.query("tablo_id");
  const isAdmin = await isTabloAdmin(supabase, tabloId, user.id);
  if (!isAdmin) {
    return c.json({ error: "You are not an admin of this tablo" }, 403);
  }
  await next();
};