'use client';

import React, { useCallback, useState } from 'react';
import useImageUpload from '../../lib/hooks/useImageUpload';
import { cn, fetcher } from '@/lib/utils';
import { SignedPayload, MessageBase, ChatEntity } from '@/lib/types';
import { useRouter } from 'next/navigation';
import Loading from '../ui/Loading';
import toast from 'react-hot-toast';
import {
  generateVideoThumbnails,
  getVideoCover,
} from '@rajesh896/video-thumbnails-generator';

export interface ImageSelectorProps {}

type Example = {
  url: string;
  initMessages: MessageBase[];
};

const ImageSelector: React.FC<ImageSelectorProps> = () => {
  const router = useRouter();
  const [isUploading, setUploading] = useState(false);

  const upload = useCallback(async (file: File, chatId?: string) => {
    const { id, signedUrl, publicUrl, fields } = await fetcher<SignedPayload>(
      '/api/sign',
      {
        method: 'POST',
        body: JSON.stringify({
          id: chatId,
          fileType: file.type,
          fileName: file.name,
        }),
      },
    );
    const formData = new FormData();
    Object.entries(fields).forEach(([key, value]) => {
      formData.append(key, value as string);
    });
    formData.append('file', file);

    const uploadResponse = await fetch(signedUrl, {
      method: 'POST',
      body: formData,
    });
    if (!uploadResponse.ok) {
      toast.error(uploadResponse.statusText);
      return;
    }
    return {
      id,
      publicUrl,
    };
  }, []);

  const { getRootProps, getInputProps, isDragActive } = useImageUpload(
    undefined,
    async files => {
      const formData = new FormData();
      if (files.length !== 1) {
        throw new Error('Only one image can be uploaded at a time');
      }
      setUploading(true);
      const reader = new FileReader();
      reader.readAsDataURL(files[0]);
      reader.onload = async () => {
        const file = files[0];
        const resp = await upload(file);
        if (!resp) {
          return;
        }
        if (file.type === 'video/mp4') {
          const thumbnails = await generateVideoThumbnails(file, 1, 'file');
          fetch(thumbnails[0])
            .then(res => res.blob())
            .then(blob => {
              const thumbnailFile = new File(
                [blob],
                file.name.replace('.mp4', '.png').replace('.MP4', '.png'),
                {
                  type: 'image/png',
                },
              );
              return upload(thumbnailFile, resp.id);
            });
        }
        await fetcher<ChatEntity>('/api/upload', {
          method: 'POST',
          headers: {
            'Content-Type': 'application/json',
          },
          body: JSON.stringify({
            id: resp.id,
            url: resp.publicUrl,
          }),
        });
        setUploading(false);
        router.push(`/chat/${resp.id}`);
      };
    },
  );
  return (
    <div
      {...getRootProps()}
      className={cn(
        'dropzone border-2 border-dashed border-gray-400 w-full h-64 flex items-center justify-center rounded-lg mt-4 cursor-pointer',
        isDragActive && 'bg-gray-500/50 border-solid',
      )}
    >
      <input {...getInputProps()} />
      <div className="text-gray-400 text-md">
        {isUploading ? (
          <Loading />
        ) : (
          'Start using Vision Agent by selecting an image'
        )}
      </div>
    </div>
  );
};

export default ImageSelector;