'use client';

import * as React from 'react';
import { TextInput } from './TextInput';
import { FontPreview } from './FontPreview';
import { FontSelector } from './FontSelector';
import { TextTemplates } from './TextTemplates';
import { HistoryPanel } from './HistoryPanel';
import { ComparisonMode } from './ComparisonMode';
import { Button } from '@/components/ui/Button';
import { Card } from '@/components/ui/Card';
import { GitCompare } from 'lucide-react';
import { textToAscii } from '@/lib/figlet/figletService';
import { getFontList } from '@/lib/figlet/fontLoader';
import { debounce } from '@/lib/utils/debounce';
import { addRecentFont } from '@/lib/storage/favorites';
import { addToHistory, type HistoryItem } from '@/lib/storage/history';
import { decodeFromUrl, updateUrl, getShareableUrl } from '@/lib/utils/urlSharing';
import { useToast } from '@/components/ui/Toast';
import { cn } from '@/lib/utils/cn';
import type { FigletFont } from '@/types/figlet';

export function FigletConverter() {
  const [text, setText] = React.useState('Figlet UI');
  const [selectedFont, setSelectedFont] = React.useState('Standard');
  const [asciiArt, setAsciiArt] = React.useState('');
  const [fonts, setFonts] = React.useState<FigletFont[]>([]);
  const [isLoading, setIsLoading] = React.useState(false);
  const [isComparisonMode, setIsComparisonMode] = React.useState(false);
  const [comparisonFonts, setComparisonFonts] = React.useState<string[]>([]);
  const [comparisonResults, setComparisonResults] = React.useState<Record<string, string>>({});
  const { addToast } = useToast();

  // Load fonts and check URL params on mount
  React.useEffect(() => {
    getFontList().then(setFonts);

    // Check for URL parameters
    const urlState = decodeFromUrl();
    if (urlState) {
      if (urlState.text) setText(urlState.text);
      if (urlState.font) setSelectedFont(urlState.font);
    }
  }, []);

  // Generate ASCII art
  const generateAsciiArt = React.useCallback(
    debounce(async (inputText: string, fontName: string) => {
      if (!inputText) {
        setAsciiArt('');
        setIsLoading(false);
        return;
      }

      setIsLoading(true);
      try {
        const result = await textToAscii(inputText, fontName);
        setAsciiArt(result);
      } catch (error) {
        console.error('Error generating ASCII art:', error);
        setAsciiArt('Error generating ASCII art. Please try a different font.');
      } finally {
        setIsLoading(false);
      }
    }, 300),
    []
  );

  // Trigger generation when text or font changes
  React.useEffect(() => {
    generateAsciiArt(text, selectedFont);
    // Track recent fonts
    if (selectedFont) {
      addRecentFont(selectedFont);
    }
    // Update URL
    updateUrl(text, selectedFont);
  }, [text, selectedFont, generateAsciiArt]);

  // Copy to clipboard
  const handleCopy = async () => {
    if (!asciiArt) return;

    try {
      await navigator.clipboard.writeText(asciiArt);
      addToHistory(text, selectedFont, asciiArt);
      addToast('Copied to clipboard!', 'success');
    } catch (error) {
      console.error('Failed to copy:', error);
      addToast('Failed to copy', 'error');
    }
  };

  // Download as text file
  const handleDownload = () => {
    if (!asciiArt) return;

    const blob = new Blob([asciiArt], { type: 'text/plain' });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = `figlet-${selectedFont}-${Date.now()}.txt`;
    document.body.appendChild(a);
    a.click();
    document.body.removeChild(a);
    URL.revokeObjectURL(url);
  };

  // Share (copy URL to clipboard)
  const handleShare = async () => {
    const shareUrl = getShareableUrl(text, selectedFont);

    try {
      await navigator.clipboard.writeText(shareUrl);
      addToast('Shareable URL copied!', 'success');
    } catch (error) {
      console.error('Failed to copy URL:', error);
      addToast('Failed to copy URL', 'error');
    }
  };

  // Random font
  const handleRandomFont = () => {
    if (fonts.length === 0) return;
    const randomIndex = Math.floor(Math.random() * fonts.length);
    setSelectedFont(fonts[randomIndex].name);
    addToast(`Random font: ${fonts[randomIndex].name}`, 'info');
  };

  const handleSelectTemplate = (templateText: string) => {
    setText(templateText);
    addToast(`Template applied: ${templateText}`, 'info');
  };

  const handleSelectHistory = (item: HistoryItem) => {
    setText(item.text);
    setSelectedFont(item.font);
    addToast(`Restored from history`, 'info');
  };

  // Comparison mode handlers
  const handleToggleComparisonMode = () => {
    const newMode = !isComparisonMode;
    setIsComparisonMode(newMode);
    if (newMode && comparisonFonts.length === 0) {
      // Initialize with current font
      setComparisonFonts([selectedFont]);
    }
    addToast(newMode ? 'Comparison mode enabled' : 'Comparison mode disabled', 'info');
  };

  const handleAddToComparison = (fontName: string) => {
    if (comparisonFonts.includes(fontName)) {
      addToast('Font already in comparison', 'info');
      return;
    }
    if (comparisonFonts.length >= 6) {
      addToast('Maximum 6 fonts for comparison', 'info');
      return;
    }
    setComparisonFonts([...comparisonFonts, fontName]);
    addToast(`Added ${fontName} to comparison`, 'success');
  };

  const handleRemoveFromComparison = (fontName: string) => {
    setComparisonFonts(comparisonFonts.filter((f) => f !== fontName));
    addToast(`Removed ${fontName} from comparison`, 'info');
  };

  const handleCopyComparisonFont = async (fontName: string, result: string) => {
    try {
      await navigator.clipboard.writeText(result);
      addToHistory(text, fontName, result);
      addToast(`Copied ${fontName} to clipboard!`, 'success');
    } catch (error) {
      console.error('Failed to copy:', error);
      addToast('Failed to copy', 'error');
    }
  };

  const handleDownloadComparisonFont = (fontName: string, result: string) => {
    const blob = new Blob([result], { type: 'text/plain' });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = `figlet-${fontName}-${Date.now()}.txt`;
    document.body.appendChild(a);
    a.click();
    document.body.removeChild(a);
    URL.revokeObjectURL(url);
  };

  // Generate comparison results
  React.useEffect(() => {
    if (!isComparisonMode || comparisonFonts.length === 0 || !text) return;

    const generateComparisons = async () => {
      const results: Record<string, string> = {};
      for (const fontName of comparisonFonts) {
        try {
          results[fontName] = await textToAscii(text, fontName);
        } catch (error) {
          console.error(`Error generating ASCII art for ${fontName}:`, error);
          results[fontName] = 'Error generating ASCII art';
        }
      }
      setComparisonResults(results);
    };

    generateComparisons();
  }, [isComparisonMode, comparisonFonts, text]);

  return (
    <div className="grid grid-cols-1 lg:grid-cols-3 gap-6">
      {/* Left Column - Input and Preview */}
      <div className="lg:col-span-2 space-y-6">
        {/* Comparison Mode Toggle */}
        <Card className="scale-in">
          <div className="p-4 flex items-center justify-between">
            <div className="flex items-center gap-2">
              <GitCompare className={cn(
                "h-4 w-4",
                isComparisonMode ? "text-primary" : "text-muted-foreground"
              )} />
              <span className="text-sm font-medium">Comparison Mode</span>
              {isComparisonMode && comparisonFonts.length > 0 && (
                <span className="text-xs px-2 py-0.5 bg-primary/10 text-primary rounded-full font-medium slide-down">
                  {comparisonFonts.length} {comparisonFonts.length === 1 ? 'font' : 'fonts'}
                </span>
              )}
            </div>
            <Button
              variant={isComparisonMode ? 'default' : 'outline'}
              size="sm"
              onClick={handleToggleComparisonMode}
              className={cn(isComparisonMode && "shadow-lg")}
            >
              {isComparisonMode ? 'Disable' : 'Enable'}
            </Button>
          </div>
        </Card>

        <TextTemplates onSelectTemplate={handleSelectTemplate} />

        <HistoryPanel onSelectHistory={handleSelectHistory} />

        <TextInput
          value={text}
          onChange={setText}
          placeholder="Type your text here..."
        />

        {isComparisonMode ? (
          <ComparisonMode
            text={text}
            selectedFonts={comparisonFonts}
            fontResults={comparisonResults}
            onRemoveFont={handleRemoveFromComparison}
            onCopyFont={handleCopyComparisonFont}
            onDownloadFont={handleDownloadComparisonFont}
          />
        ) : (
          <FontPreview
            text={asciiArt}
            font={selectedFont}
            isLoading={isLoading}
            onCopy={handleCopy}
            onDownload={handleDownload}
            onShare={handleShare}
          />
        )}
      </div>

      {/* Right Column - Font Selector */}
      <div className="lg:col-span-1">
        <FontSelector
          fonts={fonts}
          selectedFont={selectedFont}
          onSelectFont={setSelectedFont}
          onRandomFont={handleRandomFont}
          isComparisonMode={isComparisonMode}
          comparisonFonts={comparisonFonts}
          onAddToComparison={handleAddToComparison}
        />
      </div>
    </div>
  );
}