"use client";

import { useCallback, useEffect, useState } from "react";
import { Link, useLocation, useNavigate } from "@/lib/router";
import { api } from "@/lib/api";
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card";
import { Badge } from "@/components/ui/badge";
import { Input } from "@/components/ui/input";
import { Button } from "@/components/ui/button";
import ProgressiveImage from "@/components/ProgressiveImage";
import type * as Types from "@/lib/types";
import { formatJalali, formatNumberPersian, formatToman, getEventCardImageUrl } from "@/lib/utils";
import type { EventsContentPage } from "@/lib/content-cms";

type EventsProps = {
  content: EventsContentPage;
  initialEvents?: Types.EventListItemSchema[];
  initialSearch?: string;
};

function labelPrice(event: Types.EventListItemSchema) {
  const price = Number(event?.price ?? 0);
  return price <= 0 ? "رایگان" : formatToman(price);
}

function modeFa(eventType: Types.EventListItemSchema["event_type"]) {
  return eventType === "online" ? "آنلاین" : "حضوری";
}

function spotsLeft(event: Types.EventListItemSchema) {
  const cap = Number(event.capacity);
  const used = Number(event.registration_count);
  return cap - used;
}

function isAvailable(event: Types.EventListItemSchema) {
  const now = new Date();
  const end = new Date(event.registration_end_date ?? event.start_time);
  const timeOk = end.getTime() > now.getTime();
  return timeOk && spotsLeft(event) > 0;
}

function notAvailableReasonFa(event: Types.EventListItemSchema) {
  const now = new Date();
  const end = new Date(event.registration_end_date ?? event.start_time);
  if (end.getTime() <= now.getTime()) return "ثبت‌نام پایان‌یافته";
  if (spotsLeft(event) <= 0) return "ظرفیت تکمیل";
  return "غیرقابل ثبت‌نام";
}

export default function Events({
  content,
  initialEvents = [],
  initialSearch = "",
}: EventsProps) {
  const navigate = useNavigate();
  const location = useLocation();
  const [events, setEvents] = useState<Types.EventListItemSchema[]>(initialEvents);
  const [search, setSearch] = useState(initialSearch);
  const [loading, setLoading] = useState(!initialEvents.length && !initialSearch);

  useEffect(() => {
    setEvents(initialEvents);
  }, [initialEvents]);

  useEffect(() => {
    setSearch(initialSearch);
  }, [initialSearch]);

  const loadEvents = useCallback(async () => {
    try {
      setLoading(true);
      const data = await api.getEvents({
        search: search || undefined,
        statuses: ["published", "completed"],
        limit: 30,
      });
      setEvents(data);
    } catch (error) {
      console.error("Error loading events:", error);
    } finally {
      setLoading(false);
    }
  }, [search]);

  useEffect(() => {
    loadEvents();
  }, [loadEvents]);

  useEffect(() => {
    const params = new URLSearchParams();
    if (search.trim()) {
      params.set("search", search.trim());
    }
    const basePath = location.pathname || "/events";
    const nextPath = params.size
      ? `${basePath}?${params.toString()}`
      : basePath;
    navigate(nextPath, { replace: true });
  }, [location.pathname, navigate, search]);

  return (
      <main className="min-h-screen bg-background" dir="rtl">
        <div className="container mx-auto px-4 py-8">
          <h1 className="mb-3 text-4xl font-bold">{content.title}</h1>
          {content.intro ? <p className="mb-8 max-w-3xl leading-8 text-muted-foreground">{content.intro}</p> : null}

          <div className="mb-8">
            <Input
              type="text"
              placeholder="جستجو در رویدادها..."
              aria-label="جستجو در رویدادها"
              value={search}
              onChange={(e) => setSearch(e.target.value)}
              className="max-w-md"
            />
          </div>

          {loading ? (
            <p className="text-center text-muted-foreground">در حال بارگذاری...</p>
          ) : events.length === 0 ? (
            <p className="text-center text-muted-foreground">رویدادی یافت نشد</p>
          ) : (
            <div className="grid md:grid-cols-2 lg:grid-cols-3 gap-6">
              {events.map((event) => (
                <Link key={event.id} to={`/events/${event.slug}`} className="block h-full">
                  <Card className="h-full flex flex-col hover:shadow-lg transition-shadow">
                    <div className="w-full aspect-video overflow-hidden rounded-lg">
                      <ProgressiveImage
                        src={getEventCardImageUrl(event)}
                        alt={event.title}
                        wrapperClassName="h-full w-full"
                        className="h-full w-full object-cover"
                      />
                    </div>

                    <div className="flex-1 flex flex-col justify-between">
                      <CardHeader>
                        <div className="flex items-start justify-between gap-2">
                          <CardTitle className="line-clamp-2">{event.title}</CardTitle>
                          <Badge variant="default">{modeFa(event.event_type)}</Badge>
                        </div>
                        <CardDescription>{formatJalali(event.start_time, false)}</CardDescription>
                      </CardHeader>

                      <CardContent>
                        <div className="grid gap-1 text-sm" dir="rtl">
                          <div className="flex items-center justify-between">
                            <span className="text-muted-foreground">ظرفیت رویداد</span>
                            <span className="font-medium">
                              {formatNumberPersian(Number(event?.capacity ?? 0) - Number(event?.registration_count ?? 0))}
                              /
                              {formatNumberPersian(Number(event?.capacity ?? 0))} نفر
                            </span>
                          </div>
                          <div className="flex items-center justify-between">
                            <span className="text-muted-foreground">هزینه‌ی ثبت‌نام</span>
                            <span className="font-medium">{labelPrice(event)}</span>
                          </div>
                          {isAvailable(event) ? (
                            <Button>جزئیات رویداد</Button>
                          ) : (
                            <Button variant="secondary">{notAvailableReasonFa(event)}</Button>
                          )}
                        </div>
                      </CardContent>
                    </div>
                  </Card>
                </Link>
              ))}
            </div>
          )}
        </div>
      </main>
  );
}