import React, { useState, useEffect, useRef } from 'react'
import {
  generateQRCode,
  generateSVGQRCode,
  addImageToQRCode,
  addImageToSVG,
  generateCompleteSVGQRCode,
  downloadSVG,
  fileToDataURL,
  validateImageFile
} from '../utils/qrCodeUtils'

const TextAreaComponent = () => {
  const [text, setText] = useState('')
  const [qrCodeUrl, setQrCodeUrl] = useState('')
  const [customImage, setCustomImage] = useState(null)
  const [customImageUrl, setCustomImageUrl] = useState('')
  const [imageSize, setImageSize] = useState(25) // Size as percentage of QR code
  const [foregroundColor, setForegroundColor] = useState('#0000ff') // QR code foreground color
  const [backgroundColor, setBackgroundColor] = useState('#FFFFFF') // QR code background color
  const canvasRef = useRef(null)

  // Generate QR code when text, custom image, image size, or colors change
  useEffect(() => {
    if (text.trim()) {
      generateQRCodeLocal(text)
    } else {
      setQrCodeUrl('')
    }
  }, [text, customImage, imageSize, foregroundColor, backgroundColor])

  const generateQRCodeLocal = async (inputText) => {
    try {
      // Generate QR code as data URL using utility function
      const url = await generateQRCode(inputText, foregroundColor, backgroundColor)
      
      if (customImage) {
        // Create QR code with custom image overlay
        const qrWithImage = await addImageToQRCode(url, customImageUrl, imageSize)
        setQrCodeUrl(qrWithImage)
      } else {
        setQrCodeUrl(url)
      }
    } catch (error) {
      console.error('Error generating QR code:', error)
      setQrCodeUrl('')
    }
  }

  const generateSVGQRCodeLocal = async (inputText) => {
    try {
      console.log('Base SVG generated, length:', inputText.length)
      
      if (customImage) {
        console.log('Custom image detected, adding to SVG...')
        // Add custom image to SVG using utility function
        const svgWithImage = await addImageToSVG(inputText, customImageUrl, imageSize)
        console.log('SVG with image generated, length:', svgWithImage.length)
        return svgWithImage
      } else {
        console.log('No custom image, returning base SVG')
        return inputText
      }
    } catch (error) {
      console.error('Error generating SVG QR code:', error)
      return null
    }
  }



  const exportAsSVG = async () => {
    if (!text.trim()) {
      alert('Please enter some text to generate a QR code')
      return
    }
    
    // Generate base SVG QR code using utility function
    const baseSvg = await generateSVGQRCode(text, foregroundColor, backgroundColor)
    if (!baseSvg) {
      alert('Error generating QR code')
      return
    }
    
    // Add custom image if present
    const svgContent = await generateSVGQRCodeLocal(baseSvg)
    if (svgContent) {
      // Debug: Log the SVG content to see what's being generated
      console.log('Generated SVG content:', svgContent)
      
      // Use utility function to download SVG
      downloadSVG(svgContent, 'qrcode.svg')
    }
  }



  const handleImageUpload = async (event) => {
    const file = event.target.files[0]
    if (file) {
      // Validate file using utility function
      const validation = validateImageFile(file)
      if (!validation.success) {
        alert(validation.error)
        return
      }
      
      try {
        // Convert file to data URL using utility function
        const dataUrl = await fileToDataURL(file)
        setCustomImage(file)
        setCustomImageUrl(dataUrl)
      } catch (error) {
        console.error('Error processing image file:', error)
        alert('Error processing image file')
      }
    }
  }

  const removeCustomImage = () => {
    setCustomImage(null)
    setCustomImageUrl('')
  }

  const handleTextChange = (e) => {
    setText(e.target.value)
  }

  const handleClear = () => {
    setText('')
  }

  return (
    <div className="textarea-container">
      <label htmlFor="text-input" className="textarea-label">
        Enter text to generate QR code:
      </label>
      <textarea
        id="text-input"
        value={text}
        onChange={handleTextChange}
        placeholder="Enter your text here..."
        className="textarea-input"
        rows={6}
        cols={50}
      />
      
      <div className="color-controls">
        <div className="color-input-group">
          <label htmlFor="foreground-color" className="color-label">
            QR Code Color:
          </label>
          <input
            id="foreground-color"
            type="color"
            value={foregroundColor}
            onChange={(e) => setForegroundColor(e.target.value)}
            className="color-input"
          />
          <span className="color-value">{foregroundColor}</span>
        </div>
        
        <div className="color-input-group">
          <label htmlFor="background-color" className="color-label">
            Background Color:
          </label>
          <input
            id="background-color"
            type="color"
            value={backgroundColor}
            onChange={(e) => setBackgroundColor(e.target.value)}
            className="color-input"
          />
          <span className="color-value">{backgroundColor}</span>
        </div>
      </div>
      
      <div className="image-upload-section">
        <label htmlFor="image-upload" className="image-upload-label">
          Add custom image or SVG to QR code center:
        </label>
        <div className="image-upload-controls">
          <input
            id="image-upload"
            type="file"
            accept="image/*,.svg"
            onChange={handleImageUpload}
            className="image-upload-input"
          />
          {customImage && (
            <button 
              onClick={removeCustomImage}
              className="remove-image-button"
            >
              Remove Image
            </button>
          )}
        </div>
        {customImage && (
          <div className="image-preview">
            <img 
              src={customImageUrl} 
              alt="Custom image preview" 
              className="preview-image"
            />
            <span className="image-name">{customImage.name}</span>
          </div>
        )}
        
        {customImage && (
          <div className="image-size-control">
            <label htmlFor="image-size" className="size-label">
              Image Size: {imageSize}%
            </label>
            <input
              id="image-size"
              type="range"
              min="10"
              max="40"
              value={imageSize}
              onChange={(e) => setImageSize(parseInt(e.target.value))}
              className="size-slider"
            />
            <div className="size-labels">
              <span>Small</span>
              <span>Large</span>
            </div>
          </div>
        )}
      </div>
      
      <div className="textarea-actions">
        <button 
          onClick={handleClear}
          className="clear-button"
          disabled={!text}
        >
          Clear
        </button>
        <span className="character-count">
          Characters: {text.length}
        </span>
      </div>
      
      {qrCodeUrl && (
        <div className="qr-code-container">
          <h3>QR Code {customImage && '(with custom image)'}</h3>
          <img
            src={qrCodeUrl}
            alt="QR Code"
            className="qr-code-image"
          />
          <div className="qr-code-actions">
            <button 
              onClick={exportAsSVG}
              className="export-svg-button"
            >
              Export as SVG
            </button>
          </div>
          <p className="qr-code-info">
            Scan this QR code with any QR code reader app
          </p>
        </div>
      )}
    </div>
  )
}

export default TextAreaComponent