"use client";

import Image from "next/image";
import { FaBriefcase, FaUserGraduate, FaTools, FaFileUpload } from "react-icons/fa";
import { useState } from "react";
import CvSummaryPanel from "@/components/CvSummaryPanel";

interface SectionData {
  score: number;
  suggestions: string[];
  summary: string;
  keywords: { [key: string]: number };
}

interface OpenAiStats {
  input_tokens: number;
  output_tokens: number;
  total_tokens: number;
  cost: number;
}

interface SummaryData {
  sections: {
    Summary?: SectionData;
    "Work Experience"?: SectionData;
    Education?: SectionData;
    Skills?: SectionData;
    Certifications?: SectionData;
    Projects?: SectionData;
  };
  openai_stats?: OpenAiStats;
  error?: string;
}

export default function Home() {
  const [file, setFile] = useState<File | null>(null);
  const [summaryData, setSummaryData] = useState<SummaryData | null>(null);
  const [loading, setLoading] = useState<boolean>(false);
  const [isSummaryVisible, setIsSummaryVisible] = useState<boolean>(false);
  const [showDebug, setShowDebug] = useState<boolean>(false);

  const handleFileChange = (event: React.ChangeEvent<HTMLInputElement>) => {
    if (event.target.files) {
      setFile(event.target.files[0]);
      setSummaryData(null);
      setIsSummaryVisible(false);
    }
  };

  const handleSubmit = async (event: React.FormEvent) => {
    event.preventDefault();
    if (!file) return;

    setLoading(true);
    setSummaryData(null);
    setIsSummaryVisible(false);

    const formData = new FormData();
    formData.append("cv", file);

    try {
      const response = await fetch("/api/upload-cv", {
        method: "POST",
        body: formData,
      });

      if (response.ok) {
        const parsed: SummaryData = await response.json();
        setSummaryData(parsed);
        setIsSummaryVisible(true);
      } else {
        alert("CV summary failed.");
      }
    } catch (error) {
      console.error("Error summarizing CV:", error);
      alert("An error occurred while summarizing the CV.");
    } finally {
      setLoading(false);
    }
  };

  const toggleDebug = () => {
    setShowDebug(!showDebug);
  };

  return (
    <div className="min-h-screen p-8 pb-20 gap-16 sm:p-20 font-[family-name:var(--font-geist-sans)] bg-gray-50">
      <main className="flex flex-col sm:flex-row gap-8 row-start-2 items-start">
        <div className="flex flex-col gap-8 w-full sm:w-1/2 sm:items-start">
          <h1 className="text-3xl font-bold text-gray-900">Welcome to Your CV Upgrade</h1>
          <p className="text-lg text-center sm:text-left text-gray-700">
            This platform is designed to help you enhance your CV and showcase your skills effectively.
          </p>
          <div className="flex flex-col gap-4 mt-6">
            <div className="flex items-center">
              <FaBriefcase className="text-2xl mr-2 text-gray-600" />
              <p className="text-gray-700">Highlight your professional experience and achievements.</p>
            </div>
            <div className="flex items-center">
              <FaUserGraduate className="text-2xl mr-2 text-gray-600" />
              <p className="text-gray-700">Showcase your educational background and certifications.</p>
            </div>
            <div className="flex items-center">
              <FaTools className="text-2xl mr-2 text-gray-600" />
              <p className="text-gray-700">Utilize our tools to create a standout CV that gets noticed.</p>
            </div>
          </div>

          <div className="flex flex-col items-start mt-8">
            <h2 className="mb-2 text-2xl font-bold text-gray-900">Are you ready to pimp your CV?</h2>
            <input
              type="file"
              accept=".pdf"
              onChange={handleFileChange}
              className="hidden"
              id="cv-upload"
            />
            <div className="flex space-x-2">
              <label htmlFor="cv-upload" className="inline-flex items-center justify-center px-4 py-2 border border-gray-500 rounded-md shadow-sm text-sm font-medium text-gray-700 bg-white hover:bg-gray-50 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-gray-500 cursor-pointer disabled:opacity-50">
                Upload CV
              </label>
              <button
                onClick={handleSubmit}
                className="inline-flex items-center justify-center px-4 py-2 border border-gray-500 rounded-md shadow-sm text-sm font-medium text-gray-700 bg-white hover:bg-gray-50 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-gray-500 cursor-pointer disabled:opacity-50"
                disabled={loading || !file}
              >
                {loading ? "Summarizing..." : "Summarize CV"}
              </button>
            </div>
            {file && <p className="mt-2 text-sm text-gray-700 font-normal flex items-center"><FaFileUpload className="mr-2 text-gray-600 text-2xl" /> Selected file: {file.name}</p>}
          </div>
        </div>
        {/* Right Column - CV Summary Panel */}
        <div className="w-full sm:w-1/2 sm:border-l sm:border-gray-200 sm:pl-8">
          <button onClick={toggleDebug} className="mb-4 px-4 py-2 border border-gray-500 rounded-md shadow-sm text-sm font-medium text-gray-700 bg-white hover:bg-gray-50 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-gray-500 cursor-pointer">
            {showDebug ? "Hide Debug Info" : "Show Debug Info"}
          </button>
          <div className={`${isSummaryVisible ? 'block' : 'hidden'} p-6 rounded-md`}>
            {loading ? (
              <div className="animate-pulse bg-gray-100 p-6 transition-opacity duration-500" style={{ animation: 'pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite' }}>
                <div className="h-4 bg-gray-300 rounded-md mb-2" />
                <div className="h-4 bg-gray-300 rounded-md mb-2" />
                <div className="h-4 bg-gray-300 rounded-md" />
              </div>
            ) : summaryData ? (
              <>
                {summaryData.error ? (
                  <p className="text-red-500">{summaryData.error}</p>
                ) : (
                  <CvSummaryPanel analysisData={summaryData} summary={summaryData.sections.Summary?.summary || null} />
                )}
                {summaryData.openai_stats && showDebug && (
                  <div className="mt-4 border p-4 rounded-md bg-gray-100">
                    <h4 className="text-lg font-semibold text-gray-900 mb-2">OpenAI Stats</h4>
                    <p className="text-gray-700">Input Tokens: {summaryData.openai_stats.input_tokens}</p>
                    <p className="text-gray-700">Output Tokens: {summaryData.openai_stats.output_tokens}</p>
                    <p className="text-gray-700">Total Tokens: {summaryData.openai_stats.total_tokens}</p>
                    <p className="text-gray-700">Cost: ${summaryData.openai_stats.cost}</p>
                  </div>
                )}
              </>
            ) : null}
          </div>
        </div>
      </main>
      <footer className="flex flex-col items-center justify-center mt-16 p-4 border-t border-gray-200 absolute bottom-0 left-0 right-0 w-full">
        <p className="text-center text-gray-500 text-sm mb-4">
          Powered by Vercel & OpenAI
        </p>
        <div className="flex gap-6 flex-wrap items-center justify-center">
          <a
            className="flex items-center gap-2 hover:underline hover:underline-offset-4 text-sm text-gray-600"
            href="https://nextjs.org/learn?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
            target="_blank"
            rel="noopener noreferrer"
          >
            <Image
              aria-hidden
              src="/file.svg"
              alt="File icon"
              width={16}
              height={16}
            />
            Learn
          </a>
          <a
            className="flex items-center gap-2 hover:underline hover:underline-offset-4 text-sm text-gray-600"
            href="https://vercel.com/templates?framework=next.js&utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
            target="_blank"
            rel="noopener noreferrer"
          >
            <Image
              aria-hidden
              src="/window.svg"
              alt="Window icon"
              width={16}
              height={16}
            />
            Examples
          </a>
          <a
            className="flex items-center gap-2 hover:underline hover:underline-offset-4 text-sm text-gray-600"
            href="https://nextjs.org?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
            target="_blank"
            rel="noopener noreferrer"
          >
            <Image
              aria-hidden
              src="/globe.svg"
              alt="Globe icon"
              width={16}
              height={16}
            />
            nextjs.org
          </a>
        </div>
      </footer>
    </div>
  );
}