import React, { useState, useCallback } from 'react';
import { AnalysisType, FlyerItem, Store } from '../types';
import { getQuickInsights, getDeepDiveAnalysis, searchWeb, planTripWithMaps, generateImageFromText } from '../services/geminiService';
import { LoadingSpinner } from './LoadingSpinner';
import { LightbulbIcon } from './icons/LightbulbIcon';
import { BrainIcon } from './icons/BrainIcon';
import { SearchIcon } from './icons/SearchIcon';
import { MapPinIcon } from './icons/MapPinIcon';
import { PhotoIcon } from './icons/PhotoIcon';

interface AnalysisPanelProps {
  flyerItems: FlyerItem[];
  store?: Store;
}

interface TabButtonProps {
    label: string;
    icon: React.ReactNode;
    isActive: boolean;
    onClick: () => void;
}

const TabButton: React.FC<TabButtonProps> = ({ label, icon, isActive, onClick }) => {
    const activeClasses = 'bg-brand-primary text-white';
    const inactiveClasses = 'bg-gray-200 dark:bg-gray-700 text-gray-600 dark:text-gray-300 hover:bg-gray-300 dark:hover:bg-gray-600';
    return (
        <button
            onClick={onClick}
            className={`flex-1 flex items-center justify-center space-x-2 px-4 py-2.5 text-sm font-medium rounded-md transition-colors duration-200 ${isActive ? activeClasses : inactiveClasses}`}
        >
            {icon}
            <span>{label}</span>
        </button>
    );
};

export const AnalysisPanel: React.FC<AnalysisPanelProps> = ({ flyerItems, store }) => {
  const [activeTab, setActiveTab] = useState<AnalysisType>(AnalysisType.QUICK_INSIGHTS);
  const [results, setResults] = useState<{ [key in AnalysisType]?: string }>({});
  const [sources, setSources] = useState<any[]>([]);
  const [loadingStates, setLoadingStates] = useState<{ [key in AnalysisType]?: boolean }>({});
  const [error, setError] = useState<string | null>(null);

  // State for new feature stubs
  const [generatedImageUrl, setGeneratedImageUrl] = useState<string | null>(null);
  const [isGeneratingImage, setIsGeneratingImage] = useState(false);

  const handleAnalysis = useCallback(async (type: AnalysisType) => {
    setLoadingStates(prev => ({ ...prev, [type]: true }));
    setError(null);
    try {
      let responseText = '';
      if (type === AnalysisType.QUICK_INSIGHTS) {
        responseText = await getQuickInsights(flyerItems);
      } else if (type === AnalysisType.DEEP_DIVE) {
        responseText = await getDeepDiveAnalysis(flyerItems);
      } else if (type === AnalysisType.WEB_SEARCH) {
        const { text, sources } = await searchWeb(flyerItems);
        responseText = text;
        setSources(sources);
      } else if (type === AnalysisType.PLAN_TRIP) {
          const userLocation = await new Promise<GeolocationCoordinates>((resolve, reject) => {
            navigator.geolocation.getCurrentPosition(
              (position) => resolve(position.coords),
              (error) => reject(error)
            );
          });
          const { text, sources } = await planTripWithMaps(flyerItems, store, userLocation);
          responseText = text;
          setSources(sources);
      }
      setResults(prev => ({ ...prev, [type]: responseText }));
    } catch (e: any) {
      console.error(`Analysis failed for type ${type}:`, e);
      const userFriendlyMessage = e.code === 1 ? "Please allow location access to use this feature." : `Failed to get ${type.replace('_', ' ')}. Please try again.`;
      setError(userFriendlyMessage);
    } finally {
      setLoadingStates(prev => ({ ...prev, [type]: false }));
    }
  }, [flyerItems, store]);

  const handleGenerateImage = useCallback(async () => {
    const mealPlanText = results[AnalysisType.DEEP_DIVE];
    if (!mealPlanText) return;

    setIsGeneratingImage(true);
    try {
        const base64Image = await generateImageFromText(mealPlanText);
        setGeneratedImageUrl(`data:image/png;base64,${base64Image}`);
    } catch (e: any) {
        setError(`Failed to generate image: ${e.message}`);
    } finally {
        setIsGeneratingImage(false);
    }
  }, [results]);

  const renderContent = () => {
    if (loadingStates[activeTab]) {
      return <div className="flex justify-center items-center h-48"><LoadingSpinner /></div>;
    }
    
    const resultText = results[activeTab];
    if (resultText) {
        const isSearchType = activeTab === AnalysisType.WEB_SEARCH || activeTab === AnalysisType.PLAN_TRIP;
        return (
            <div className="prose prose-sm dark:prose-invert max-w-none whitespace-pre-wrap font-sans">
                {resultText}
                {isSearchType && sources.length > 0 && (
                    <div className="mt-4">
                        <h4 className="font-semibold">Sources:</h4>
                        <ul className="list-disc pl-5">
                            {sources.map((source, index) => {
                                const uri = source.web?.uri || source.maps?.uri;
                                const title = source.web?.title || source.maps?.title || 'Map Link';
                                if (!uri) return null;
                                return (
                                    <li key={index}>
                                        <a href={uri} target="_blank" rel="noopener noreferrer" className="text-brand-primary hover:underline">
                                            {title}
                                        </a>
                                    </li>
                                )
                            })}
                        </ul>
                    </div>
                )}
                {activeTab === AnalysisType.DEEP_DIVE && (
                    <div className="mt-6 text-center">
                        {generatedImageUrl ? (
                            <img src={generatedImageUrl} alt="AI generated meal plan" className="rounded-lg shadow-md mx-auto" />
                        ) : (
                            <button
                                onClick={handleGenerateImage}
                                disabled={isGeneratingImage}
                                className="inline-flex items-center justify-center bg-indigo-500 hover:bg-indigo-600 disabled:bg-indigo-300 text-white font-bold py-2 px-4 rounded-lg"
                            >
                                {isGeneratingImage ? <><LoadingSpinner /> <span className="ml-2">Generating...</span></> : <><PhotoIcon className="w-4 h-4 mr-2"/> Generate an image for this meal plan</>}
                            </button>
                        )}
                    </div>
                )}
            </div>
        );
    }
    
    return (
        <div className="text-center py-10">
            <p className="text-gray-500 mb-4">Click below to generate AI-powered insights.</p>
            <button
              onClick={() => handleAnalysis(activeTab)}
              className="bg-brand-secondary hover:bg-brand-dark text-white font-bold py-2 px-4 rounded-lg transition-colors duration-300"
            >
              Generate {activeTab.replace('_', ' ')}
            </button>
        </div>
    );
  };

  return (
    <div className="bg-white dark:bg-gray-900 rounded-lg border border-gray-200 dark:border-gray-700 p-4">
      <div className="flex space-x-2 mb-4">
        <TabButton label="Quick Insights" icon={<LightbulbIcon className="w-4 h-4" />} isActive={activeTab === AnalysisType.QUICK_INSIGHTS} onClick={() => setActiveTab(AnalysisType.QUICK_INSIGHTS)} />
        <TabButton label="Deep Dive" icon={<BrainIcon className="w-4 h-4" />} isActive={activeTab === AnalysisType.DEEP_DIVE} onClick={() => setActiveTab(AnalysisType.DEEP_DIVE)} />
        <TabButton label="Web Search" icon={<SearchIcon className="w-4 h-4" />} isActive={activeTab === AnalysisType.WEB_SEARCH} onClick={() => setActiveTab(AnalysisType.WEB_SEARCH)} />
        <TabButton label="Plan Trip" icon={<MapPinIcon className="w-4 h-4" />} isActive={activeTab === AnalysisType.PLAN_TRIP} onClick={() => setActiveTab(AnalysisType.PLAN_TRIP)} />
      </div>
      <div className="bg-gray-50 dark:bg-gray-800 rounded-md p-4 min-h-[200px] overflow-y-auto">
        {error && <p className="text-red-500 text-center">{error}</p>}
        {renderContent()}
      </div>
    </div>
  );
};