import React, { useState, useEffect } from 'react';
import { motion, AnimatePresence } from 'framer-motion';
import { Eye, Zap, Brain, Settings, ExternalLink, FileText } from 'lucide-react';
import DocumentViewer from './DocumentViewer';

const PreviewPanel = ({ 
  file, 
  processingMode, 
  onModeChange, 
  onProcess, 
  isProcessing, 
  apiKey 
}) => {
  const [previewUrl, setPreviewUrl] = useState(null);
  const [fileInfo, setFileInfo] = useState(null);
  const [showDocumentViewer, setShowDocumentViewer] = useState(false);
  // OCR borders for future use
  // const [showOcrBorders, setShowOcrBorders] = useState(false);

  useEffect(() => {
    if (file) {
      const url = URL.createObjectURL(file);
      setPreviewUrl(url);
      
      setFileInfo({
        name: file.name,
        size: (file.size / 1024 / 1024).toFixed(2),
        type: file.type,
        lastModified: new Date(file.lastModified).toLocaleString()
      });

      return () => URL.revokeObjectURL(url);
    }
  }, [file]);

  const processingModes = [
    {
      id: 'standard',
      name: 'Standard Mode',
      model: 'Gemini 2.5 Flash',
      icon: <Zap size={20} />,
      description: 'Fast processing',
      features: ['Same features as Pro', 'Faster speed', 'Slightly less accuracy'],
      gradient: 'linear-gradient(135deg, #667eea 0%, #764ba2 100%)'
    },
    {
      id: 'structured',
      name: 'Structured Mode',
      model: 'Gemini 2.5 Pro',
      icon: <Brain size={20} />,
      description: 'Maximum accuracy',
      features: ['Best accuracy', 'Advanced formatting', 'Slower processing'],
      gradient: 'linear-gradient(135deg, #f093fb 0%, #f5576c 100%)'
    }
  ];

  return (
    <>
      {showDocumentViewer && (
        <DocumentViewer 
          file={file} 
          onBack={() => setShowDocumentViewer(false)} 
        />
      )}
      
      <div className="preview-panel">
        <div className="preview-grid">
        {/* File Preview */}
        <motion.div
          className="preview-section glass-panel"
          initial={{ opacity: 0, x: -20 }}
          animate={{ opacity: 1, x: 0 }}
          transition={{ duration: 0.5 }}
        >
          <div className="section-header">
            <Eye size={20} />
            <h3>File Preview</h3>
          </div>
          
          <div className="preview-container">
            {previewUrl && (
              <motion.div
                className="preview-image-container"
                initial={{ scale: 0.9, opacity: 0 }}
                animate={{ scale: 1, opacity: 1 }}
                transition={{ duration: 0.3 }}
              >
                {file.type === 'application/pdf' ? (
                  <div className="pdf-preview glass-preview">
                    <div className="preview-content">
                      <div className="document-icon">
                        <FileText size={48} />
                      </div>
                      <p className="preview-title">PDF Document</p>
                      <span className="pdf-note">Ready for processing</span>
                      <motion.button
                        className="preview-button"
                        onClick={() => setShowDocumentViewer(true)}
                        whileHover={{ scale: 1.05 }}
                        whileTap={{ scale: 0.95 }}
                      >
                        <ExternalLink size={16} />
                        Open Viewer
                      </motion.button>
                    </div>
                  </div>
                ) : file.type === 'text/html' || file.name.toLowerCase().endsWith('.html') ? (
                  <div className="html-preview glass-preview">
                    <div className="preview-content">
                      <div className="document-icon">
                        <FileText size={48} />
                      </div>
                      <p className="preview-title">HTML Document</p>
                      <span className="html-note">Ready for processing</span>
                      <motion.button
                        className="preview-button"
                        onClick={() => setShowDocumentViewer(true)}
                        whileHover={{ scale: 1.05 }}
                        whileTap={{ scale: 0.95 }}
                      >
                        <ExternalLink size={16} />
                        Open Viewer
                      </motion.button>
                    </div>
                  </div>
                ) : (
                  <img 
                    src={previewUrl} 
                    alt="Preview" 
                    className="preview-image"
                  />
                )}
              </motion.div>
            )}
            
            {fileInfo && (
              <div className="file-info nested-panel">
                <div className="info-grid">
                  <div className="info-item">
                    <span className="info-label">Name:</span>
                    <span className="info-value">{fileInfo.name}</span>
                  </div>
                  <div className="info-item">
                    <span className="info-label">Size:</span>
                    <span className="info-value">{fileInfo.size} MB</span>
                  </div>
                  <div className="info-item">
                    <span className="info-label">Type:</span>
                    <span className="info-value">{fileInfo.type}</span>
                  </div>
                  <div className="info-item">
                    <span className="info-label">Modified:</span>
                    <span className="info-value">{fileInfo.lastModified}</span>
                  </div>
                </div>
              </div>
            )}
          </div>
        </motion.div>

        {/* Processing Options */}
        <motion.div
          className="options-section glass-panel"
          initial={{ opacity: 0, x: 20 }}
          animate={{ opacity: 1, x: 0 }}
          transition={{ duration: 0.5, delay: 0.1 }}
        >
          <div className="section-header">
            <Settings size={20} />
            <h3>Processing Options</h3>
          </div>
          
          <div className="processing-modes">
            {processingModes.map((mode, index) => (
              <motion.div
                key={mode.id}
                className={`mode-card nested-panel ${processingMode === mode.id ? 'active' : ''}`}
                onClick={() => onModeChange(mode.id)}
                whileHover={{ scale: 1.02, y: -2 }}
                whileTap={{ scale: 0.98 }}
                initial={{ opacity: 0, y: 20 }}
                animate={{ opacity: 1, y: 0 }}
                transition={{ delay: index * 0.1 }}
              >
                <div className="mode-header">
                  <div className="mode-icon" style={{ background: mode.gradient }}>
                    {mode.icon}
                  </div>
                  <div className="mode-info">
                    <h4>{mode.name}</h4>
                    <span className="mode-model">{mode.model}</span>
                  </div>
                </div>
                
                <p className="mode-description">{mode.description}</p>
                
                <div className="mode-features">
                  {mode.features.map((feature, idx) => (
                    <span key={idx} className="feature-tag">
                      {feature}
                    </span>
                  ))}
                </div>
                
                {processingMode === mode.id && (
                  <motion.div
                    className="mode-indicator"
                    layoutId="modeIndicator"
                    style={{
                      position: 'absolute',
                      top: 0,
                      left: 0,
                      right: 0,
                      bottom: 0,
                      background: 'rgba(99, 102, 241, 0.1)',
                      borderRadius: '12px',
                      zIndex: -1,
                      border: '1px solid rgba(99, 102, 241, 0.3)'
                    }}
                    transition={{
                      type: "spring",
                      stiffness: 500,
                      damping: 30
                    }}
                  />
                )}
              </motion.div>
            ))}
          </div>
          
          <motion.button
            className="process-button flowing-button"
            onClick={onProcess}
            disabled={!apiKey || isProcessing}
            whileHover={{ scale: 1.05 }}
            whileTap={{ scale: 0.95 }}
            style={{
              width: '100%',
              marginTop: '24px',
              background: isProcessing 
                ? 'linear-gradient(135deg, #6b7280 0%, #4b5563 100%)'
                : 'linear-gradient(135deg, #667eea 0%, #764ba2 100%)'
            }}
          >
            <AnimatePresence mode="wait">
              {isProcessing ? (
                <motion.div
                  key="processing"
                  initial={{ opacity: 0 }}
                  animate={{ opacity: 1 }}
                  exit={{ opacity: 0 }}
                  className="button-content"
                >
                  <motion.div
                    className="processing-spinner"
                    animate={{ rotate: 360 }}
                    transition={{ duration: 1, repeat: Infinity, ease: "linear" }}
                  >
                    ⚡
                  </motion.div>
                  Processing...
                </motion.div>
              ) : (
                <motion.div
                  key="ready"
                  initial={{ opacity: 0 }}
                  animate={{ opacity: 1 }}
                  exit={{ opacity: 0 }}
                  className="button-content"
                >
                  🚀 Extract Text
                </motion.div>
              )}
            </AnimatePresence>
          </motion.button>
          
          {!apiKey && (
            <motion.p
              className="api-warning"
              initial={{ opacity: 0 }}
              animate={{ opacity: 1 }}
              style={{
                color: 'rgba(251, 86, 7, 0.8)',
                fontSize: '0.75rem',
                textAlign: 'center',
                marginTop: '8px'
              }}
            >
              Please enter your Google API Key to continue
            </motion.p>
          )}
        </motion.div>
      </div>

      <style jsx>{`
        .preview-panel {
          width: 100%;
          min-height: auto;
          padding-bottom: 40px;
        }

        .preview-grid {
          display: grid;
          grid-template-columns: 1fr 1fr;
          gap: 24px;
          height: 100%;
        }

        .section-header {
          display: flex;
          align-items: center;
          gap: 12px;
          margin-bottom: 24px;
          color: var(--text-primary);
        }

        .section-header h3 {
          font-size: 1.25rem;
          font-weight: 600;
        }

        .preview-container {
          display: flex;
          flex-direction: column;
          gap: 16px;
        }

        .preview-image-container {
          border-radius: 12px;
          overflow: hidden;
          background: rgba(100, 100, 100, 0.1);
          backdrop-filter: blur(25px);
          -webkit-backdrop-filter: blur(25px);
        }

        .preview-image {
          width: 100%;
          height: 300px;
          object-fit: contain;
          background: rgba(100, 100, 100, 0.1);
        }

        .pdf-preview {
          height: 300px;
          display: flex;
          flex-direction: column;
          align-items: center;
          justify-content: center;
          gap: 12px;
          background: rgba(100, 100, 100, 0.1);
        }

        .pdf-icon {
          font-size: 4rem;
          filter: drop-shadow(0 0 20px rgba(99, 102, 241, 0.3));
        }

        .pdf-note {
          font-size: 0.75rem;
          color: var(--text-muted);
        }

        .file-info {
          padding: 16px;
        }

        .info-grid {
          display: grid;
          grid-template-columns: 1fr 1fr;
          gap: 12px;
        }

        .info-item {
          display: flex;
          flex-direction: column;
          gap: 4px;
        }

        .info-label {
          font-size: 0.75rem;
          color: var(--text-muted);
          font-weight: 500;
        }

        .info-value {
          font-size: 0.875rem;
          color: var(--text-secondary);
          word-break: break-all;
        }

        .processing-modes {
          display: flex;
          flex-direction: column;
          gap: 16px;
          margin-bottom: 24px;
        }

        .mode-card {
          cursor: pointer;
          transition: all 0.3s ease;
          position: relative;
          overflow: hidden;
        }

        .mode-card.active {
          border-color: rgba(99, 102, 241, 0.3);
        }

        .mode-header {
          display: flex;
          align-items: center;
          gap: 12px;
          margin-bottom: 12px;
        }

        .mode-icon {
          width: 40px;
          height: 40px;
          border-radius: 10px;
          display: flex;
          align-items: center;
          justify-content: center;
          color: white;
        }

        .mode-info h4 {
          font-size: 1rem;
          font-weight: 600;
          color: var(--text-primary);
          margin-bottom: 2px;
        }

        .mode-model {
          font-size: 0.75rem;
          color: var(--text-muted);
        }

        .mode-description {
          font-size: 0.875rem;
          color: var(--text-secondary);
          margin-bottom: 12px;
        }

        .mode-features {
          display: flex;
          flex-wrap: wrap;
          gap: 6px;
        }

        .feature-tag {
          background: rgba(100, 100, 100, 0.1);
          color: rgba(255, 255, 255, 0.8);
          padding: 4px 8px;
          border-radius: 6px;
          font-size: 0.75rem;
          font-weight: 500;
          backdrop-filter: blur(10px);
        }

        .button-content {
          display: flex;
          align-items: center;
          justify-content: center;
          gap: 8px;
        }

        .processing-spinner {
          font-size: 1.2rem;
        }

        @media (max-width: 768px) {
          .preview-grid {
            grid-template-columns: 1fr;
          }
          
          .info-grid {
            grid-template-columns: 1fr;
          }
        }

        .glass-preview {
          background: rgba(0, 0, 0, 0.2);
          backdrop-filter: blur(25px);
          -webkit-backdrop-filter: blur(25px);
          border: 1px solid rgba(255, 255, 255, 0.1);
          border-radius: 16px;
          overflow: hidden;
        }

        .preview-content {
          display: flex;
          flex-direction: column;
          align-items: center;
          justify-content: center;
          gap: 12px;
          padding: 32px;
        }

        .document-icon {
          color: rgba(79, 172, 254, 0.8);
          filter: drop-shadow(0 0 20px rgba(79, 172, 254, 0.4));
        }

        .preview-title {
          font-size: 1.25rem;
          font-weight: 600;
          color: var(--text-primary);
          margin: 0;
        }

        .pdf-note, .html-note {
          font-size: 0.875rem;
          color: var(--text-muted);
          margin: 0;
        }

        .preview-button {
          display: flex;
          align-items: center;
          gap: 8px;
          padding: 12px 20px;
          background: linear-gradient(135deg, #4facfe, #8b5cf6);
          border: none;
          border-radius: 8px;
          color: white;
          font-size: 0.875rem;
          font-weight: 500;
          cursor: pointer;
          transition: all 0.3s ease;
          margin-top: 8px;
        }

        .preview-button:hover {
          box-shadow: 0 4px 15px rgba(79, 172, 254, 0.3);
          transform: translateY(-1px);
        }
      `}</style>
      </div>
    </>
  );
};

export default PreviewPanel;