'use client';

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

interface DownloadOptionsModalProps {
    onDownloadCurrent: () => void;
    onDownloadAll: () => void;
    onClose: () => void;
    currentVideoIndex: number;
    totalVideos: number;
    /** 当前视频是否生成失败 */
    isCurrentVideoFailed: boolean;
    /** 是否为最终视频阶段 */
    isFinalStage?: boolean;
}

/**
 * Download options modal component with glass morphism style.
 * @param {DownloadOptionsModalProps} props - modal properties.
 */
function DownloadOptionsModal(props: DownloadOptionsModalProps) {
    const { onDownloadCurrent, onDownloadAll, onClose, currentVideoIndex, totalVideos, isCurrentVideoFailed, isFinalStage = false } = props;
    const containerRef = useRef<HTMLDivElement | null>(null);

    useEffect(() => {
        const originalOverflow = document.body.style.overflow;
        document.body.style.overflow = 'hidden';
        return () => {
            document.body.style.overflow = originalOverflow;
        };
    }, []);

    return (
        <div
            ref={containerRef}
            data-alt="download-options-overlay"
            className="fixed inset-0 z-[1000] flex items-center justify-center bg-black/60"
        >
            <div
                data-alt="download-options-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"
                role="dialog"
                aria-modal="true"
                aria-labelledby="download-options-title"
                onClick={(e) => e.stopPropagation()}
            >
                <button
                    data-alt="close-button"
                    className="absolute top-4 right-4 w-6 h-6 rounded-full bg-white/10 hover:bg-white/20 border border-white/10 flex items-center justify-center text-white transition-all active:scale-95"
                    onClick={onClose}
                    aria-label="Close"
                >
                    <X size={14} />
                </button>
                <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 text-purple-400">
                        <Download />
                    </div>
                    <h3 id="download-options-title" data-alt="modal-title" className="text-base font-semibold">
                        Download Options
                    </h3>
                </div>

                <div data-alt="modal-body" className="mt-4">
                    <p data-alt="modal-description" className="text-sm text-white/80 text-center">
                        Choose your download preference
                    </p>

                    {!isCurrentVideoFailed && (
                        <div data-alt="stats-info" className="mt-3 rounded-lg bg-white/5 border border-white/10 p-3 text-center">
                            <div className="text-xs text-white/60">Current video</div>
                            <div className="text-sm font-medium">{currentVideoIndex + 1} / {totalVideos}</div>
                        </div>
                    )}
                </div>

                <div data-alt="modal-actions" className="mt-6 space-y-3">
                    {!isCurrentVideoFailed && (
                        <button
                            data-alt="download-current-button"
                            className="w-full px-4 py-2.5 rounded-lg bg-gradient-to-br from-purple-600/80 to-purple-700/80 hover:from-purple-500/80 hover:to-purple-600/80 text-white font-medium transition-all flex items-center justify-center gap-2"
                            onClick={() => {
                                onDownloadCurrent();
                                onClose();
                            }}
                        >
                            <Download size={16} />
                            {isFinalStage ? 'Download Final Video' : 'Download Current Video'}
                        </button>
                    )}
                    <button
                        data-alt="download-all-button"
                        className="w-full px-4 py-2.5 rounded-lg bg-gradient-to-br from-purple-500/60 to-purple-600/60 hover:from-purple-500/80 hover:to-purple-600/80 text-white font-medium transition-all flex items-center justify-center gap-2 border border-purple-400/30"
                        onClick={() => {
                            onDownloadAll();
                            onClose();
                        }}
                    >
                        <ArrowDownWideNarrow size={16} />
                        Download All Videos ({totalVideos})
                    </button>
                </div>
            </div>
        </div>
    );
}

/**
 * Opens a download options modal with glass morphism style.
 * @param {DownloadOptionsModalProps} options - download options and callbacks.
 */
export function showDownloadOptionsModal(options: Omit<DownloadOptionsModalProps, 'onClose'>): void {
    if (typeof window === 'undefined' || typeof document === 'undefined') {
        return;
    }

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

    let root: Root | null = null;
    try {
        root = createRoot(mount);
    } catch {
        if (mount.parentNode) {
            mount.parentNode.removeChild(mount);
        }
        return;
    }

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

    root.render(
        <DownloadOptionsModal {...options} onClose={close} />
    );
}