"use client";
import React, { useState, useEffect, useCallback, useRef } from "react";
import FormPage from './FormPage';
import { CardData } from "../exportType/types";
import SwipeCards from "../components/Cards";
import { ChatSetting } from "../exportType/types";
import { FormData, PROFICIENCY_LEVELS } from './formTypes';

// --- Helper function to get default form data ---
const getDefaultFormData = (): FormData => ({
  Hackathon: '',
  mainTheme: '',
  tracksStack: [''],
  students: [{
    studentName: '',
    skills: [{ skillName: '', proficiency: PROFICIENCY_LEVELS[1] }]
  }],
});

// --- New Initializer Function ---
const getInitialState = () => {
  if (typeof window === 'undefined') {
    return {
      data: getDefaultFormData(),
      showForm: true,
      runEffect: false
    };
  }
  const storedFormData = localStorage.getItem('formData');
  if (storedFormData) {
    localStorage.removeItem('formData');
    return {
      data: JSON.parse(storedFormData) as FormData,
      showForm: false,
      runEffect: true,
    };
  }
  return {
    data: getDefaultFormData(),
    showForm: true,
    runEffect: false
  };
};

export default function Home() {

  const [ideaResponse, setIdeaResponse] = useState<string>("");
  const [generatedCards, setGeneratedCards] = useState<CardData[]>([]); // New state for parsed cards
  const [initialState] = useState(getInitialState);
  const [showForm, setShowForm] = useState(initialState.showForm);
  const initialIdeaGenerationAttempted = useRef(false);

  const [settings] = useState<ChatSetting>({
    temperature: 1,
    model: "gemini-2.5-flash-lite",
    systemInstruction: `You are an elite hackathon idea generator. Your task is to choose at lease two track and generate five different creative, feasible, and relevant project idea.
The output MUST be in Markdown format and strictly follow this structure:
### Project Idea Title
**Track** [print out the track you used]
**Concept:** [A concise, single paragraph description of the product and its primary function.]`,
  });

  const generateIdeas = useCallback(async (dataToProcess: FormData) => {
    const parseAiResponse = (markdownString: string): CardData[] => {
      console.log("Raw AI Response:", markdownString);
      const ideas: CardData[] = [];
      const ideaBlocks = markdownString.split("### ").filter(block => block.trim() !== "");

      ideaBlocks.forEach((block, index) => {
        const titleMatch = block.match(/^(.*?)(?=\n\*\*Track\*\*|$)/s);
        const trackMatch = block.match(/\*\*Track\*\*\s*:\s*(.*?)(?=\n\*\*Concept\*\*|$)/s);
        const conceptMatch = block.match(/\*\*Concept:\*\*\s*(.*)/s);

        const title = titleMatch ? titleMatch[1].trim() : `Idea ${index + 1}`;
        const summary = conceptMatch ? conceptMatch[1].trim() : "No concept provided.";
        const tracksRaw = trackMatch ? trackMatch[1].trim() : "";
        const tracks = tracksRaw.split(',').map(track => track.trim()).filter(track => track !== '');

        ideas.push({
          id: index + 1,
          title,
          tracks,
          summary,
        });
      });
      console.log("Parsed Cards:", ideas);
      return ideas;
    };

    const submissionData: FormData = {
      ...dataToProcess,
      tracksStack: dataToProcess.tracksStack.filter(tracks => tracks.trim() !== ''),
      students: dataToProcess.students
        .map(student => ({
          ...student,
          skills: student.skills.filter(skill => skill.skillName.trim() !== ''),
        }))
        .filter(student => student.studentName.trim() !== '' || student.skills.length > 0),
    };

    const prompt = `
    Hackathon: ${submissionData.Hackathon}
    Main Theme: ${submissionData.mainTheme}
    Required Tracks Stack: ${submissionData.tracksStack.join(', ')}
    Team Members and Skills: ${submissionData.students.map(s =>
      `${s.studentName || 'Unamed Member'} (Skills: ${s.skills.map(sk => `${sk.skillName} - ${sk.proficiency}`).join(', ')})`
    ).join('; ')}
    
    Using the SYSTEM INSTRUCTIONS, generate 5 project ideas based on the data above.`;

    try {
      setIdeaResponse("Generating ideas... Please wait.");
      setGeneratedCards([]);
      const response = await fetch("/api/generate-idea", {
        method: "POST",
        headers: {
          "Content-Type": "application/json",
        },
        body: JSON.stringify({
          prompt: prompt,
          settings: settings,
        }),
      });

      const data = await response.json();

      if (data.error || !response.ok) {
        console.error("AI Error:", data.error);
        setIdeaResponse(`Error: Failed to generate idea. ${data.error || response.statusText}`);
        return;
      }

      setIdeaResponse(data.response);
      const parsedCards = parseAiResponse(data.response);
      setGeneratedCards(parsedCards);

    } catch (error) {
      console.error("Request Failed:", error);
      let errorMessage = "An unknown error occurred.";
      if (error instanceof Error) {
        errorMessage = error.message;
      } else if (typeof error === 'string') {
        errorMessage = error;
      }
      setIdeaResponse(`A network error occurred. Please try again. Details: ${errorMessage}`);
    }
  }, [settings]);

  useEffect(() => {
    if (initialState.runEffect && !initialIdeaGenerationAttempted.current) {
      // eslint-disable-next-line react-hooks/set-state-in-effect
      generateIdeas(initialState.data);
      initialIdeaGenerationAttempted.current = true;
    }
  }, [initialState, generateIdeas]);

  const handleFormSubmitFromFormPage = (submittedData: FormData) => {
    setShowForm(false);
    generateIdeas(submittedData);
  };

  // --- JSX Rendering ---
  return (
    <main className="min-h-screen bg-gray-50 flex items-start justify-center p-4 sm:p-6 font-inter">
      <div className="w-full max-w-2xl bg-white p-8 shadow-2xl rounded-xl mt-8">
        {showForm ? (
          <FormPage onFormSubmit={handleFormSubmitFromFormPage} />
        ) : (
          <>
            {generatedCards.length > 0 ? (
              <SwipeCards initialCards={generatedCards} />
            ) : (
              <>
                <h1 className="text-3xl font-extrabold text-center text-gray-800 mb-8 tracking-tight">
                  Generated Project Idea 💡
                </h1>
                <div className="mt-8 p-4 bg-yellow-50 rounded-lg border border-yellow-200">
                  <h2 className="text-xl font-bold text-gray-700 mb-2">Generated Ideas:</h2>
                  <div
                    className="prose max-w-none"
                    dangerouslySetInnerHTML={{ __html: ideaResponse.replace(/\n/g, '<br/>') }}
                  />
                  {ideaResponse === "" && <p className="text-gray-500">Submit the form to generate project ideas.</p>}
                </div>
              </>
            )}
            <button
              onClick={() => setShowForm(true)}
              className="mt-6 w-full flex justify-center py-3 px-4 border border-transparent rounded-lg shadow-lg text-lg font-semibold text-white bg-blue-600 hover:bg-blue-700 transition duration-150"
            >
              Go Back to Form
            </button>
          </>
        )}
      </div>
    </main>
  );
}