'use client';

import { useState, type DragEvent, type RefObject } from 'react';
import {
  Upload, File, CheckCircle, XCircle, Loader2,
  Copy, ExternalLink, Trash2, Globe, AlertTriangle,
} from 'lucide-react';
import { formatBytes } from '@/lib/helpers';
import { getSettings } from '@/lib/storage';

export interface FileEntry {
  id: string;
  file: File;
  preview?: string;
  status: 'pending' | 'uploading' | 'done' | 'error';
  result?: { cid: string; size: number };
  errorMsg?: string;
  date?: string;
}

interface QuickUploadProps {
  files: FileEntry[];
  dragOver: boolean;
  uploading: boolean;
  uploadIndex: number;
  uploadDone: boolean;
  copied: string | null;
  inputRef: RefObject<HTMLInputElement | null>;
  onAddFiles: (files: FileList | File[]) => void;
  onRemoveFile: (id: string) => void;
  onDragOver: (e: DragEvent) => void;
  onDragLeave: () => void;
  onDrop: (e: DragEvent) => void;
  onBrowse: () => void;
  onInputChange: (e: React.ChangeEvent<HTMLInputElement>) => void;
  onStartUpload: () => void;
  onCopyCid: (cid: string) => void;
  onCopyShareLink: (cid: string) => void;
  onClearAll: () => void;
  gatewayLink: (cid: string) => string;
}

export default function QuickUpload({
  files, dragOver, uploading, uploadIndex, uploadDone, copied,
  inputRef, onAddFiles, onRemoveFile, onDragOver, onDragLeave, onDrop,
  onBrowse, onInputChange, onStartUpload, onCopyCid, onCopyShareLink, onClearAll, gatewayLink,
}: QuickUploadProps) {

  const s = getSettings();
  const maxFiles = s.maxFiles;
  const maxFileSize = s.maxFileSize;

  const allowedExts = s.allowedFileTypes
    ? s.allowedFileTypes.split(',').map(e => e.trim().toLowerCase()).filter(Boolean)
    : null;

  const [fileTypeError, setFileTypeError] = useState<string | null>(null);

  const doneCount = files.filter(f => f.status === 'done').length;
  const errorCount = files.filter(f => f.status === 'error').length;
  const totalCount = files.length;
  const allDone = files.every(f => f.status === 'done' || f.status === 'error');

  function filterAllowedFiles(fileList: File[]): { accepted: File[]; rejected: string[] } {
    if (!allowedExts) return { accepted: fileList, rejected: [] };
    const accepted: File[] = [];
    const rejected: string[] = [];
    for (const f of fileList) {
      const ext = f.name.split('.').pop()?.toLowerCase();
      if (ext && allowedExts.includes(ext)) {
        accepted.push(f);
      } else {
        rejected.push(f.name);
      }
    }
    return { accepted, rejected };
  }

  function handleLocalDrop(e: DragEvent) {
    e.preventDefault();
    onDragLeave();
    if (e.dataTransfer.files.length > 0) {
      const fileArr = Array.from(e.dataTransfer.files);
      const { accepted, rejected } = filterAllowedFiles(fileArr);
      if (rejected.length > 0) {
        setFileTypeError(`${rejected.length} bestand(en) overgeslagen (type niet toegestaan): ${rejected.join(', ')}`);
        setTimeout(() => setFileTypeError(null), 5000);
      }
      if (accepted.length > 0) onAddFiles(accepted);
    }
  }

  function handleLocalInputChange(e: React.ChangeEvent<HTMLInputElement>) {
    if (e.target.files && e.target.files.length > 0) {
      const fileArr = Array.from(e.target.files);
      const { accepted, rejected } = filterAllowedFiles(fileArr);
      if (rejected.length > 0) {
        setFileTypeError(`${rejected.length} bestand(en) overgeslagen (type niet toegestaan): ${rejected.join(', ')}`);
        setTimeout(() => setFileTypeError(null), 5000);
      }
      if (accepted.length > 0) onAddFiles(accepted);
    }
    e.target.value = '';
  }

  return (
    <div>
      {/* File type error warning */}
      {fileTypeError && (
        <div className="mb-4 flex items-center gap-2 p-3 rounded-xl bg-accent-rose/10 border border-accent-rose/30 text-sm text-accent-rose">
          <AlertTriangle className="w-4 h-4 shrink-0" />
          <span>{fileTypeError}</span>
        </div>
      )}

      {/* Drop zone */}
      {!uploading && !uploadDone && (
        <div
          onDragOver={onDragOver}
          onDragLeave={onDragLeave}
          onDrop={files.length < maxFiles ? handleLocalDrop : undefined}
          onClick={files.length < maxFiles ? onBrowse : undefined}
          className={`relative border-2 border-dashed rounded-xl p-10 text-center transition-all duration-200 cursor-pointer ${
            dragOver
              ? 'border-brand-400 bg-brand-500/10'
              : 'border-surface-700 hover:border-surface-500 bg-surface-900/50'
          }`}
        >
          <input
            ref={inputRef}
            type="file"
            multiple
            className="hidden"
            onChange={files.length < maxFiles ? handleLocalInputChange : undefined}
            disabled={uploading || files.length >= maxFiles}
          />
          <div className="flex flex-col items-center gap-3">
            <Upload className="w-10 h-10 text-surface-500" />
            <div>
              <p className="text-sm text-surface-300">
                <span className="text-brand-400 font-medium">Click to browse</span> or drag &amp; drop files
              </p>
              <p className="text-xs text-surface-500 mt-1">
                Up to {maxFiles} files, max {formatBytes(maxFileSize)} each
              </p>
            </div>
          </div>
        </div>
      )}

      {/* File list */}
      {files.length > 0 && (
        <div className="mt-6 space-y-2">
          <div className="flex items-center justify-between">
            <span className="text-sm text-surface-400">
              {totalCount} file{totalCount !== 1 ? 's' : ''} selected
              {uploading && <> &middot; Uploading {uploadIndex}/{totalCount}</>}
            </span>
            {!uploading && !allDone && (
              <button
                onClick={onClearAll}
                className="text-xs text-surface-500 hover:text-accent-rose transition-colors"
              >
                Clear all
              </button>
            )}
          </div>

              {uploading && (
            <div className="w-full h-1.5 rounded-full bg-surface-800 overflow-hidden">
              <div
                className="h-full rounded-full bg-gradient-to-r from-brand-500 to-accent-cyan transition-all duration-300"
                style={{ width: `${(uploadIndex / totalCount) * 100}%` }}
              />
            </div>
          )}

              <div className="space-y-2">
            {files.map((entry, idx) => (
              <div
                key={entry.id}
                className={`glass rounded-xl p-3 flex items-center gap-3 transition-all duration-200 animate-fade-in ${
                  entry.status === 'done' ? 'border-l-2 border-l-accent-green' :
                  entry.status === 'error' ? 'border-l-2 border-l-accent-rose' : ''
                }`}
                style={{ animationDelay: `${idx * 30}ms` }}
              >
                  <div className="w-10 h-10 rounded-lg bg-surface-800 flex items-center justify-center shrink-0 overflow-hidden">
                  {entry.preview ? (
                    <img src={entry.preview} alt="" className="w-full h-full object-cover" />
                  ) : (
                    <File className="w-5 h-5 text-surface-500" />
                  )}
                </div>

                  <div className="flex-1 min-w-0">
                  <div className="flex items-center gap-2">
                    <span className="text-sm text-surface-200 truncate">{entry.file.name}</span>
                    {entry.status === 'done' && entry.result && (
                      <CheckCircle className="w-3.5 h-3.5 text-accent-green shrink-0" />
                    )}
                    {entry.status === 'error' && (
                      <XCircle className="w-3.5 h-3.5 text-accent-rose shrink-0" />
                    )}
                  </div>
                  <div className="flex items-center gap-3 mt-0.5">
                    <span className="text-xs text-surface-500">{formatBytes(entry.file.size)}</span>
                    {entry.status === 'uploading' && (
                      <span className="text-xs text-brand-400 flex items-center gap-1">
                        <Loader2 className="w-3 h-3 animate-spin" />
                        Uploading…
                      </span>
                    )}
                    {entry.status === 'done' && entry.result?.cid && (
                      <span className="text-xs font-mono text-surface-400 truncate max-w-[160px]">
                        {entry.result.cid.slice(0, 16)}…
                      </span>
                    )}
                    {entry.status === 'error' && (
                      <span className="text-xs text-accent-rose truncate max-w-[200px]">
                        {entry.errorMsg}
                      </span>
                    )}
                  </div>
                </div>

                  <div className="flex items-center gap-1 shrink-0">
                  {entry.status === 'done' && entry.result && (
                    <>
                      <button
                        onClick={() => onCopyCid(entry.result!.cid)}
                        className="p-1.5 rounded-lg hover:bg-surface-700 transition-colors group"
                        title="Copy CID"
                      >
                        {copied === entry.result!.cid ? (
                          <CheckCircle className="w-3.5 h-3.5 text-accent-green" />
                        ) : (
                          <Copy className="w-3.5 h-3.5 text-surface-500 group-hover:text-surface-300" />
                        )}
                      </button>
                      <a
                        href={gatewayLink(entry.result!.cid)}
                        target="_blank"
                        rel="noopener noreferrer"
                        className="p-1.5 rounded-lg hover:bg-surface-700 transition-colors group"
                        title="Open in gateway"
                      >
                        <ExternalLink className="w-3.5 h-3.5 text-surface-500 group-hover:text-surface-300" />
                      </a>
                    </>
                  )}
                  {entry.status === 'pending' && !uploading && (
                    <button
                      onClick={() => onRemoveFile(entry.id)}
                      className="p-1.5 rounded-lg hover:bg-surface-700 transition-colors group"
                      title="Remove"
                    >
                      <Trash2 className="w-3.5 h-3.5 text-surface-500 group-hover:text-accent-rose" />
                    </button>
                  )}
                </div>
              </div>
            ))}
          </div>
        </div>
      )}

      {/* Action buttons */}
      {files.length > 0 && !allDone && (
        <div className="mt-4">
          <button
            onClick={onStartUpload}
            disabled={uploading || files.filter(f => f.status === 'pending').length === 0}
            className="flex items-center gap-2 px-6 py-2.5 rounded-xl bg-brand-600 hover:bg-brand-500 disabled:opacity-40 disabled:cursor-not-allowed text-white text-sm font-medium transition-colors"
          >
            {uploading ? (
              <><Loader2 className="w-4 h-4 animate-spin" /> Uploading…</>
            ) : (
              <><Upload className="w-4 h-4" /> Upload All ({files.filter(f => f.status === 'pending').length})</>
            )}
          </button>
        </div>
      )}

      {/* Results summary */}
      {uploadDone && (
        <div className="mt-6 glass rounded-xl p-5 animate-fade-in">
          <div className="flex items-center justify-between mb-4">
            <div className="flex items-center gap-2">
              {errorCount === 0 ? (
                <CheckCircle className="w-5 h-5 text-accent-green" />
              ) : (
                <XCircle className="w-5 h-5 text-accent-rose" />
              )}
              <span className="text-sm font-medium text-white">
                {doneCount}/{totalCount} files uploaded
              </span>
            </div>
            <button
              onClick={onClearAll}
              className="flex items-center gap-1 text-xs text-brand-400 hover:text-brand-300 transition-colors"
            >
              <Upload className="w-3 h-3" />
              Upload more
            </button>
          </div>

          {/* Per-file result details */}
          {files.filter(f => f.status === 'done').map(entry => entry.result?.cid && (
            <div key={entry.id} className="flex items-center justify-between py-2 px-3 rounded-lg bg-surface-800/50 mb-1.5">
              <div className="flex items-center gap-3 min-w-0 flex-1">
                <span className="text-sm text-surface-300 truncate max-w-[150px]">{entry.file.name}</span>
                <span className="text-xs font-mono text-surface-500 truncate max-w-[120px]">{entry.result.cid.slice(0, 16)}…</span>
                <span className="text-xs text-surface-500">{formatBytes(entry.result.size ?? 0)}</span>
              </div>
              <div className="flex items-center gap-1 shrink-0">
                <button
                  onClick={() => onCopyCid(entry.result!.cid)}
                  className="p-1.5 rounded-lg hover:bg-surface-700 transition-colors"
                  title="Copy CID"
                >
                  {copied === entry.result!.cid ? (
                    <CheckCircle className="w-3.5 h-3.5 text-accent-green" />
                  ) : (
                    <Copy className="w-3.5 h-3.5 text-surface-500" />
                  )}
                </button>
                <button
                  onClick={() => onCopyShareLink(entry.result!.cid)}
                  className="p-1.5 rounded-lg hover:bg-surface-700 transition-colors"
                  title="Copy share link"
                >
                  {copied === `gw-${entry.result!.cid}` ? (
                    <CheckCircle className="w-3.5 h-3.5 text-accent-green" />
                  ) : (
                    <Globe className="w-3.5 h-3.5 text-surface-500" />
                  )}
                </button>
                <a
                  href={gatewayLink(entry.result!.cid)}
                  target="_blank"
                  rel="noopener noreferrer"
                  className="p-1.5 rounded-lg hover:bg-surface-700 transition-colors"
                  title="Open in gateway"
                >
                  <ExternalLink className="w-3.5 h-3.5 text-surface-500" />
                </a>
              </div>
            </div>
          ))}
        </div>
      )}

      {/* Empty state */}
      {files.length === 0 && !uploading && (
        <div className="mt-6 glass rounded-xl p-8 text-center">
          <Upload className="w-8 h-8 text-surface-600 mx-auto mb-3" />
          <p className="text-sm text-surface-500">
            Drag files above or click to browse. No crypto payment needed for quick uploads.
          </p>
        </div>
      )}
    </div>
  );
}