import React, { useState } from 'react';
import { Hash, Upload, Download } from 'lucide-react';
import ToolLayout from '../components/ToolLayout';
import CopyButton from '../components/CopyButton';

const Base64Tool = () => {
  const [input, setInput] = useState('');
  const [output, setOutput] = useState('');
  const [mode, setMode] = useState('encode'); // 'encode' or 'decode'

  const encodeBase64 = () => {
    try {
      const encoded = btoa(unescape(encodeURIComponent(input)));
      setOutput(encoded);
    } catch (err) {
      setOutput(`Error: ${err.message}`);
    }
  };

  const decodeBase64 = () => {
    try {
      const decoded = decodeURIComponent(escape(atob(input)));
      setOutput(decoded);
    } catch (err) {
      setOutput(`Error: Invalid Base64 string`);
    }
  };

  const handleProcess = () => {
    if (mode === 'encode') {
      encodeBase64();
    } else {
      decodeBase64();
    }
  };

  const handleFileUpload = (event) => {
    const file = event.target.files[0];
    if (file) {
      const reader = new FileReader();
      reader.onload = (e) => {
        if (mode === 'encode') {
          setInput(e.target.result);
        } else {
          // For decode mode, read as text
          const textReader = new FileReader();
          textReader.onload = (textEvent) => {
            setInput(textEvent.target.result);
          };
          textReader.readAsText(file);
        }
      };
      
      if (mode === 'encode') {
        reader.readAsText(file);
      } else {
        reader.readAsText(file);
      }
    }
  };

  const clearAll = () => {
    setInput('');
    setOutput('');
  };

  const loadSample = () => {
    if (mode === 'encode') {
      setInput('Hello, World! This is a sample text for Base64 encoding.');
    } else {
      setInput('SGVsbG8sIFdvcmxkISBUaGlzIGlzIGEgc2FtcGxlIHRleHQgZm9yIEJhc2U2NCBlbmNvZGluZy4=');
    }
  };

  return (
    <ToolLayout
      title="Base64 Encoder/Decoder"
      description="Convert text to Base64 and back with support for files"
      icon={Hash}
    >
      {/* Mode Toggle */}
      <div className="flex bg-gray-100 dark:bg-gray-800 rounded-lg p-1 mb-6 w-fit">
        <button
          onClick={() => setMode('encode')}
          className={`px-4 py-2 rounded-md font-medium transition-colors ${
            mode === 'encode'
              ? 'bg-white dark:bg-gray-700 text-primary-600 shadow-sm'
              : 'text-gray-600 dark:text-gray-400'
          }`}
        >
          Encode
        </button>
        <button
          onClick={() => setMode('decode')}
          className={`px-4 py-2 rounded-md font-medium transition-colors ${
            mode === 'decode'
              ? 'bg-white dark:bg-gray-700 text-primary-600 shadow-sm'
              : 'text-gray-600 dark:text-gray-400'
          }`}
        >
          Decode
        </button>
      </div>

      {/* Controls */}
      <div className="flex flex-wrap gap-3 mb-6">
        <button onClick={handleProcess} className="tool-button">
          {mode === 'encode' ? 'Encode to Base64' : 'Decode from Base64'}
        </button>
        <label className="tool-button-secondary cursor-pointer flex items-center space-x-2">
          <Upload className="h-4 w-4" />
          <span>Upload File</span>
          <input
            type="file"
            onChange={handleFileUpload}
            className="hidden"
            accept=".txt,.json,.xml,.csv"
          />
        </label>
        <button onClick={loadSample} className="tool-button-secondary">
          Load Sample
        </button>
        <button onClick={clearAll} className="tool-button-secondary">
          Clear All
        </button>
      </div>

      {/* Input/Output Grid */}
      <div className="grid grid-cols-1 lg:grid-cols-2 gap-6">
        {/* Input */}
        <div className="space-y-2">
          <label className="block text-sm font-medium text-gray-700 dark:text-gray-300">
            {mode === 'encode' ? 'Text to Encode' : 'Base64 to Decode'}
          </label>
          <div className="relative">
            <textarea
              value={input}
              onChange={(e) => setInput(e.target.value)}
              placeholder={
                mode === 'encode' 
                  ? 'Enter text to encode to Base64...' 
                  : 'Enter Base64 string to decode...'
              }
              className="tool-input h-96"
            />
          </div>
        </div>

        {/* Output */}
        <div className="space-y-2">
          <label className="block text-sm font-medium text-gray-700 dark:text-gray-300">
            {mode === 'encode' ? 'Base64 Output' : 'Decoded Text'}
          </label>
          <div className="relative">
            <textarea
              value={output}
              readOnly
              placeholder={
                mode === 'encode' 
                  ? 'Base64 encoded text will appear here...' 
                  : 'Decoded text will appear here...'
              }
              className="tool-input h-96 bg-gray-50 dark:bg-gray-800"
            />
            {output && <CopyButton text={output} />}
          </div>
        </div>
      </div>

      {/* Usage Tips */}
      <div className="bg-blue-50 dark:bg-blue-900/20 border border-blue-200 dark:border-blue-800 rounded-md p-4 mt-6">
        <h4 className="text-blue-800 dark:text-blue-200 font-medium mb-2">Usage Tips</h4>
        <ul className="text-blue-700 dark:text-blue-300 text-sm space-y-1">
          <li>• Base64 encoding is commonly used for data transmission and storage</li>
          <li>• Upload text files to encode/decode their contents</li>
          <li>• Encoded Base64 strings are safe for URLs and email transmission</li>
          <li>• Use the toggle to switch between encode and decode modes</li>
        </ul>
      </div>
    </ToolLayout>
  );
};

export default Base64Tool;