"use client";
import { Dispatch, SetStateAction, useCallback, useState, useRef } from "react";
import { FileRejection, useDropzone } from "react-dropzone";
import axios from "axios";
import { Message } from "@/lib/types";
import Button from "../components/ui/Button";
import { MdClose } from "react-icons/md";
import { AnimatePresence, motion } from "framer-motion";
import Link from "next/link";
import Card from "../components/ui/Card";
import PageHeading from "../components/ui/PageHeading";

export default function UploadPage() {
  const [message, setMessage] = useState<Message | null>(null);
  const [isPending, setIsPending] = useState(false);
  const [files, setFiles] = useState<File[]>([]);
  const [pendingFileIndex, setPendingFileIndex] = useState<number>(0);
  const urlInputRef = useRef<HTMLInputElement | null>(null);

  const crawlWebsite = useCallback(async () => {
    // Validate URL
    const url = urlInputRef.current ? urlInputRef.current.value : null;
    if (!url || !isValidUrl(url)) {
      // Assuming you have a function to validate URLs
      setMessage({
        type: "error",
        text: "Invalid URL",
      });
      return;
    }

    // Configure parameters
    const config = {
      url: url,
      js: false,
      depth: 1,
      max_pages: 100,
      max_time: 60,
    };

    try {
      const response = await axios.post(
        `${process.env.NEXT_PUBLIC_BACKEND_URL}/crawl`,
        config
      );

      setMessage({
        type: response.data.type,
        text: response.data.message,
      });
    } catch (error: any) {
      setMessage({
        type: "error",
        text: "Failed to crawl website: " + error.toString(),
      });
    }
  }, []);

  const upload = useCallback(async (file: File) => {
    const formData = new FormData();
    formData.append("file", file);
    try {
      const response = await axios.post(
        `${process.env.NEXT_PUBLIC_BACKEND_URL}/upload`,
        formData
      );

      setMessage({
        type: response.data.type,
        text:
          (response.data.type === "success"
            ? "File uploaded successfully: "
            : "") + JSON.stringify(response.data.message),
      });
    } catch (error: any) {
      setMessage({
        type: "error",
        text: "Failed to upload file: " + error.toString(),
      });
    }
  }, []);

  const onDrop = (acceptedFiles: File[], fileRejections: FileRejection[]) => {
    if (fileRejections.length > 0) {
      setMessage({ type: "error", text: "File too big." });
      return;
    }
    setMessage(null);
    for (let i = 0; i < acceptedFiles.length; i++) {
      const file = acceptedFiles[i];
      const isAlreadyInFiles =
        files.filter((f) => f.name === file.name && f.size === file.size)
          .length > 0;
      if (isAlreadyInFiles) {
        setMessage({ type: "warning", text: `${file.name} was already added` });
        acceptedFiles.splice(i, 1);
      }
    }
    setFiles((files) => [...files, ...acceptedFiles]);
  };

  const uploadAllFiles = async () => {
    setIsPending(true);
    setMessage(null);
    // files.forEach((file) => upload(file));
    for (const file of files) {
      await upload(file);
      setPendingFileIndex((i) => i + 1);
    }
    setPendingFileIndex(0);
    setIsPending(false);
  };

  const { getRootProps, getInputProps, isDragActive, open } = useDropzone({
    onDrop,
    noClick: true,
    maxSize: 100000000, // 1 MB
  });

  return (
    <main>
      <section
        {...getRootProps()}
        // className="w-full h-full min-h-screen text-center flex flex-col items-center gap-5 pt-32 outline-none"
        className="w-full outline-none pt-20 flex flex-col gap-5 items-center justify-center p-6"
      >
        <PageHeading
          title="Add Knowledge"
          subtitle="Upload files to your second brain"
        />
        {/* Wrap the cards in a flex container */}
        <div className="flex justify-center gap-5">
          {/* Assign a width of 50% to each card */}
          <Card className="w-1/2">
            <input {...getInputProps()} />
            <div className="text-center mt-2 p-6 max-w-sm w-full flex flex-col gap-5 items-center">
              {files.length > 0 ? (
                <AnimatePresence>
                  {files.map((file, i) => (
                    <FileComponent
                      key={file.name + file.size}
                      file={file}
                      setFiles={setFiles}
                    />
                  ))}
                </AnimatePresence>
              ) : null}

              {isDragActive ? (
                <p className="text-blue-600">Drop the files here...</p>
              ) : (
                <button
                  onClick={open}
                  className="opacity-50 cursor-pointer hover:opacity-100 hover:underline transition-opacity"
                >
                  Drag and drop some files here, or click to browse files
                </button>
              )}
            </div>
          </Card>
          {/* Assign a width of 50% to each card */}
          <Card className="w-1/2">
            <div className="text-center mt-2 p-6 max-w-sm w-full flex flex-col gap-5 items-center">
              <input
                ref={urlInputRef}
                type="text"
                placeholder="Enter a website URL"
                className="dark:bg-black"
              />
              <button
                onClick={crawlWebsite}
                className="opacity-50 cursor-pointer hover:opacity-100 hover:underline transition-opacity"
              >
                Crawl Website
              </button>
            </div>
          </Card>
        </div>
        <div className="flex flex-col items-center justify-center gap-5">
          <Button isLoading={isPending} onClick={uploadAllFiles} className="">
            {isPending ? `Adding - ${files[pendingFileIndex].name}` : "Add"}
          </Button>
          <Link href={"/chat"}>
            <Button variant={"secondary"} className="py-3">
              Start Chatting with your brain
            </Button>
          </Link>
        </div>
      </section>
      {message && (
        <div
          className={`fixed bottom-0 inset-x-0 m-4 p-4 max-w-sm mx-auto rounded ${
            message.type === "success"
              ? "bg-green-500"
              : message.type === "warning"
              ? "bg-yellow-600"
              : "bg-red-500"
          }`}
        >
          <p className="text-white">{message.text}</p>
        </div>
      )}
    </main>
  );
}

const FileComponent = ({
  file,
  setFiles,
}: {
  file: File;
  setFiles: Dispatch<SetStateAction<File[]>>;
}) => {
  return (
    <motion.div
      initial={{ x: "-10%", opacity: 0 }}
      animate={{ x: "0%", opacity: 1 }}
      exit={{ x: "10%", opacity: 0 }}
      className="flex py-2 dark:bg-black border-b border-black/10 dark:border-white/25 w-full text-left leading-none"
    >
      <div className="flex flex-col gap-1 flex-1">
        <span className="flex-1 mr-10">{file.name}</span>
        <span className="text-xs opacity-50">
          {(file.size / 1000).toFixed(3)} kb
        </span>
      </div>
      <button
        role="remove file"
        className="ml-5 text-xl text-red-500 px-5"
        onClick={() =>
          setFiles((files) =>
            files.filter((f) => f.name !== file.name || f.size !== file.size)
          )
        }
      >
        <MdClose />
      </button>
    </motion.div>
  );
};

function isValidUrl(string: string) {
  try {
    new URL(string);
    return true;
  } catch (_) {
    return false;
  }
}