import { useState, useEffect, useCallback, useRef } from "react";
import { ANIMATION_DURATIONS } from "~/utils/constants";
import { loadMessages, hasValidSession } from "~/utils/session-storage";

export const useScreenState = (isOpen: boolean) => {
  const [showWelcomeScreen, setShowWelcomeScreen] = useState(true);
  const [isFadingOut, setIsFadingOut] = useState(false);
  const [showSuggestionScreen, setShowSuggestionScreen] = useState(false);
  const hasShownWelcome = useRef(false);
  const hasUserSentFirstMessage = useRef(false);
  const hasCheckedExistingMessages = useRef(false);

  useEffect(() => {
    if (!hasCheckedExistingMessages.current) {
      const existingMessages = loadMessages();
      const hasValidSessionData = hasValidSession();

      if (hasValidSessionData && existingMessages.length > 0) {
        hasShownWelcome.current = true;
        hasUserSentFirstMessage.current = true;
        setShowWelcomeScreen(false);
        setShowSuggestionScreen(false);
      }

      hasCheckedExistingMessages.current = true;
    }
  }, []);
  useEffect(() => {
    if (isOpen && !hasShownWelcome.current) {
      setShowWelcomeScreen(true);
      setIsFadingOut(false);
      setShowSuggestionScreen(false);
      hasShownWelcome.current = true;
    } else if (
      isOpen &&
      hasShownWelcome.current &&
      !hasUserSentFirstMessage.current
    ) {
      setShowWelcomeScreen(false);
      setShowSuggestionScreen(true);
    } else if (
      isOpen &&
      hasShownWelcome.current &&
      hasUserSentFirstMessage.current
    ) {
      setShowWelcomeScreen(false);
      setShowSuggestionScreen(false);
    }
  }, [isOpen]);
  useEffect(() => {
    if (isOpen && showWelcomeScreen && !hasUserSentFirstMessage.current) {
      const timer = setTimeout(() => {
        setIsFadingOut(true);
        setTimeout(() => {
          setShowWelcomeScreen(false);
          setShowSuggestionScreen(true);
        }, ANIMATION_DURATIONS.FAST);
      }, ANIMATION_DURATIONS.VERY_SLOW);

      return () => clearTimeout(timer);
    }
  }, [isOpen, showWelcomeScreen]);

  const goToChat = useCallback(() => {
    hasShownWelcome.current = true;
    hasUserSentFirstMessage.current = true;
    setShowWelcomeScreen(false);
    setShowSuggestionScreen(false);
  }, []);

  const resetToWelcomeScreen = useCallback(() => {
    hasShownWelcome.current = false;
    hasUserSentFirstMessage.current = false;
    setShowWelcomeScreen(true);
    setIsFadingOut(false);
    setShowSuggestionScreen(false);
  }, []);

  return {
    showWelcomeScreen,
    isFadingOut,
    showSuggestionScreen,
    goToChat,
    resetToWelcomeScreen
  };
};