'use client';

import React, { useEffect, useRef } from 'react';
import { createRoot, Root } from 'react-dom/client';

type QueueStatus = 'waiting' | 'process' | string;

interface H5QueueNotificationProps {
    position: number;
    estimatedMinutes: number;
    status: QueueStatus;
    onCancel?: () => void;
    onRefresh?: () => void;
    onClose?: () => void;
}

function QueueNotificationModal(props: H5QueueNotificationProps) {
    const { position, estimatedMinutes, status, onCancel, onClose } = props;
    const containerRef = useRef<HTMLDivElement | null>(null);

    // 禁用 ESC 关闭，保留空 effect 结构便于未来拓展
    useEffect(() => {
        return () => {};
    }, []);

    useEffect(() => {
        // Prevent background scroll on mobile while modal is open
        const originalOverflow = document.body.style.overflow;
        document.body.style.overflow = 'hidden';
        return () => {
            document.body.style.overflow = originalOverflow;
        };
    }, []);

    const message = status === 'process'
        ? 'Your work is being produced. Please wait until it is completed before creating a new work.'
        : `Your work is waiting for production at the ${position} position`;

    return (
        <div
            ref={containerRef}
            data-alt="queue-overlay"
            className="fixed inset-0 z-[1000] flex items-center justify-center bg-black/60"
        >
            <div
                data-alt="queue-modal"
                className="relative w-11/12 max-w-sm rounded-2xl bg-white/5 border border-white/10 backdrop-blur-xl shadow-2xl p-6 text-white"
            >
                {/* 去除右上角关闭按钮，避免除取消以外的关闭路径 */}

                <div data-alt="modal-header" className="flex flex-col items-center text-center gap-2">
                    <div data-alt="modal-icon" className="w-10 h-10 rounded-full bg-white/10 flex items-center justify-center text-lg">
                        🎬
                    </div>
                    <h3 data-alt="modal-title" className="text-base font-semibold">Queue Reminder</h3>
                </div>

                <div data-alt="modal-body" className="mt-4 space-y-4">
                    <p data-alt="queue-description" className="text-sm text-white/80">
                        {message}
                    </p>

                    {status !== 'process' && (
                        <div data-alt="stats-grid" className="grid grid-cols-2 gap-3">
                            <div data-alt="stat-position" className="rounded-lg bg-white/5 border border-white/10 p-3">
                                <div className="text-[11px] text-white/60">Position</div>
                                <div className="text-sm font-medium">#{position}</div>
                            </div>
                            <div data-alt="stat-eta" className="rounded-lg bg-white/5 border border-white/10 p-3">
                                <div className="text-[11px] text-white/60">ETA</div>
                                <div className="text-sm font-medium">~{estimatedMinutes} min</div>
                            </div>
                        </div>
                    )}
                </div>

                <div data-alt="modal-actions" className="mt-6 space-y-3">
                    <button
                        data-alt="refresh-button"
                        className="w-full px-4 py-2 rounded-lg bg-[#9144b0] text-white font-medium transition-colors"
                        onClick={() => {
                            // 刷新仅触发回调，不关闭弹窗
                            if (status !== 'process') {
                              props.onRefresh?.();
                            } else {
                              onCancel?.();
                              onClose?.();
                            }
                        }}
                    >
                        {status !== 'process' ? 'Refresh' : 'OK'}
                    </button>
                    {status !== 'process' && (
                      <button
                        data-alt="cancel-queue-button"
                        className="w-full text-sm text-[#ab50d0] underline underline-offset-2 decoration-[#9144b0]/60"
                        onClick={() => {
                            onCancel?.();
                            onClose?.();
                        }}
                      >
                          Cancel queue →
                      </button>
                    )}
                </div>
            </div>
        </div>
    );
}

/**
 * Opens a lightweight H5-styled dark modal queue notification.
 * @param {number} position - Current queue position.
 * @param {number} estimatedMinutes - Estimated waiting minutes.
 * @param {QueueStatus} status - Queue status: 'waiting' | 'process' | string.
 * @param {() => void} onCancel - Callback when user confirms cancel.
 * @returns {() => void} - Close function to dismiss the modal programmatically.
 */
export function showQueueNotification(
    position: number,
    estimatedMinutes: number,
    status: QueueStatus,
    onCancel?: () => void,
    onRefresh?: () => void
): () => void {
    if (typeof window === 'undefined' || typeof document === 'undefined') {
        return () => {};
    }

    const mount = document.createElement('div');
    mount.setAttribute('data-alt', 'queue-root');
    document.body.appendChild(mount);

    let root: Root | null = null;
    try {
        root = createRoot(mount);
    } catch {
        // Fallback cleanup if root creation fails
        document.body.removeChild(mount);
        return () => {};
    }

    const close = () => {
        try {
            root?.unmount();
        } finally {
            if (mount.parentNode) {
                mount.parentNode.removeChild(mount);
            }
        }
    };

    root.render(
        <QueueNotificationModal
            position={position}
            estimatedMinutes={estimatedMinutes}
            status={status}
            onCancel={onCancel}
            onRefresh={onRefresh}
            onClose={close}
        />
    );

    return close;
}