import React, { useState, useEffect } from 'react';
import './App.css';

function App() {
  const [modelInfo, setModelInfo] = useState(null);
  const [trainingMetrics, setTrainingMetrics] = useState(null);
  const [prediction, setPrediction] = useState(null);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState(null);
  
  // Form data for prediction
  const [formData, setFormData] = useState({
    plant: '',
    scientificName: '',
    age: '',
    sex: '',
    year: ''
  });

  const API_URL = 'http://localhost:5000/api';

  useEffect(() => {
    checkModelStatus();
  }, []);

  const checkModelStatus = async () => {
    try {
      const response = await fetch(`${API_URL}/model/info`);
      const data = await response.json();
      if (data.success) {
        setModelInfo(data.info);
      }
    } catch (err) {
      console.log('Model not yet trained');
    }
  };

  const handleFileUpload = async (event) => {
    const file = event.target.files[0];
    if (!file) return;

    setLoading(true);
    setError(null);

    const formData = new FormData();
    formData.append('file', file);

    try {
      const response = await fetch(`${API_URL}/train`, {
        method: 'POST',
        body: formData
      });

      const data = await response.json();
      
      if (data.success) {
        setTrainingMetrics(data.metrics);
        checkModelStatus();
        alert('Model trained successfully!');
      } else {
        setError(data.error || 'Training failed');
      }
    } catch (err) {
      setError('Error training model: ' + err.message);
    } finally {
      setLoading(false);
    }
  };

  const handleInputChange = (e) => {
    setFormData({
      ...formData,
      [e.target.name]: e.target.value
    });
  };

  const handlePredict = async (e) => {
    e.preventDefault();
    setLoading(true);
    setError(null);
    setPrediction(null);

    // Convert form data to model input format
    const inputData = createInputData(formData);

    try {
      const response = await fetch(`${API_URL}/predict`, {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json'
        },
        body: JSON.stringify(inputData)
      });

      const data = await response.json();
      
      if (data.success) {
        setPrediction(data.predictions);
      } else {
        setError(data.error || 'Prediction failed');
      }
    } catch (err) {
      setError('Error making prediction: ' + err.message);
    } finally {
      setLoading(false);
    }
  };

  const createInputData = (form) => {
    // Initialize all features to 0
    const input = {};
    
    // Set plant name
    const plantKey = `Plant_Name_${form.plant}`;
    input[plantKey] = 1;
    
    // Set scientific name
    const sciKey = `Scientific_Name_${form.scientificName}`;
    input[sciKey] = 1;
    
    // Set sex counts (simplified)
    input['Sex_Male_Count'] = form.sex === 'Male' ? 1 : 0;
    input['Sex_Female_Count'] = form.sex === 'Female' ? 1 : 0;
    
    // Set age range
    if (form.age >= 18 && form.age <= 44) input['18-44_Years'] = 1;
    else if (form.age >= 45 && form.age <= 64) input['45-64_Years'] = 1;
    else if (form.age >= 65 && form.age <= 74) input['65-74_Years'] = 1;
    else if (form.age >= 75) input['>=75_years'] = 1;
    
    // Set year
    if (form.year) input[form.year] = 1;
    
    // Set geography
    input['Geo_Asia'] = 1;
    
    return input;
  };

  return (
    <div className="App">
      <header className="App-header">
        <h1>🌿 Adverse Drug Reaction Prediction System</h1>
        <p>Linear Regression Model for Herbal Medicine ADR Prediction</p>
      </header>

      <div className="container">
        {/* Model Training Section */}
        <section className="card">
          <h2>📊 Model Training</h2>
          <div className="upload-section">
            <label htmlFor="file-upload" className="file-label">
              {loading ? 'Training...' : 'Upload Training Dataset (CSV)'}
            </label>
            <input
              id="file-upload"
              type="file"
              accept=".csv"
              onChange={handleFileUpload}
              disabled={loading}
            />
          </div>

          {trainingMetrics && (
            <div className="metrics">
              <h3>Training Metrics</h3>
              <div className="metrics-grid">
                <div className="metric">
                  <span className="metric-label">R² Score:</span>
                  <span className="metric-value">{trainingMetrics.r2_score.toFixed(4)}</span>
                </div>
                <div className="metric">
                  <span className="metric-label">RMSE:</span>
                  <span className="metric-value">{trainingMetrics.rmse.toFixed(4)}</span>
                </div>
                <div className="metric">
                  <span className="metric-label">MAE:</span>
                  <span className="metric-value">{trainingMetrics.mae.toFixed(4)}</span>
                </div>
                <div className="metric">
                  <span className="metric-label">Training Samples:</span>
                  <span className="metric-value">{trainingMetrics.training_samples}</span>
                </div>
              </div>
            </div>
          )}

          {modelInfo && (
            <div className="model-info">
              <p>✅ Model Status: <strong>Trained</strong></p>
              <p>Features: {modelInfo.n_features} | Targets: {modelInfo.n_targets}</p>
            </div>
          )}
        </section>

        {/* Prediction Section */}
        <section className="card">
          <h2>🔮 Make Prediction</h2>
          <form onSubmit={handlePredict} className="prediction-form">
            <div className="form-group">
              <label>Plant Name:</label>
              <select name="plant" value={formData.plant} onChange={handleInputChange} required>
                <option value="">Select Plant</option>
                <option value="Akapulko">Akapulko</option>
                <option value="Ampalaya">Ampalaya</option>
                <option value="Bawang">Bawang</option>
                <option value="Bayabas">Bayabas</option>
                <option value="Lagundi">Lagundi</option>
                <option value="Sambong">Sambong</option>
              </select>
            </div>

            <div className="form-group">
              <label>Scientific Name:</label>
              <select name="scientificName" value={formData.scientificName} onChange={handleInputChange} required>
                <option value="">Select Scientific Name</option>
                <option value="Allium sativum">Allium sativum</option>
                <option value="Blumea balsamifera">Blumea balsamifera</option>
                <option value="Momordica charantia">Momordica charantia</option>
                <option value="Psidium guajava">Psidium guajava</option>
                <option value="Senna alata">Senna alata</option>
                <option value="Vitex negundo">Vitex negundo</option>
              </select>
            </div>

            <div className="form-row">
              <div className="form-group">
                <label>Age:</label>
                <input
                  type="number"
                  name="age"
                  value={formData.age}
                  onChange={handleInputChange}
                  min="1"
                  max="120"
                  required
                />
              </div>

              <div className="form-group">
                <label>Sex:</label>
                <select name="sex" value={formData.sex} onChange={handleInputChange} required>
                  <option value="">Select</option>
                  <option value="Male">Male</option>
                  <option value="Female">Female</option>
                </select>
              </div>

              <div className="form-group">
                <label>Year:</label>
                <input
                  type="number"
                  name="year"
                  value={formData.year}
                  onChange={handleInputChange}
                  min="1980"
                  max="2025"
                  required
                />
              </div>
            </div>

            <button type="submit" className="predict-btn" disabled={loading || !modelInfo}>
              {loading ? 'Predicting...' : 'Predict ADR Risk'}
            </button>
          </form>

          {error && (
            <div className="error-message">
              ⚠️ {error}
            </div>
          )}

          {prediction && (
            <div className="results">
              <h3>🎯 Prediction Results</h3>
              
              <div className="result-section">
                <h4>Top ADR Categories</h4>
                <div className="predictions-list">
                  {prediction.top_adr_categories.map((item, idx) => (
                    <div key={idx} className="prediction-item">
                      <span className="prediction-rank">#{idx + 1}</span>
                      <span className="prediction-name">{item.name}</span>
                      <div className="prediction-bar">
                        <div 
                          className="prediction-fill"
                          style={{ width: `${Math.max(0, Math.min(100, item.score * 100))}%` }}
                        ></div>
                      </div>
                      <span className="prediction-score">{(item.score * 100).toFixed(2)}%</span>
                    </div>
                  ))}
                </div>
              </div>

              <div className="result-section">
                <h4>Top ADR Subcategories</h4>
                <div className="predictions-list">
                  {prediction.top_adr_subcategories.map((item, idx) => (
                    <div key={idx} className="prediction-item">
                      <span className="prediction-rank">#{idx + 1}</span>
                      <span className="prediction-name">{item.name}</span>
                      <div className="prediction-bar">
                        <div 
                          className="prediction-fill"
                          style={{ width: `${Math.max(0, Math.min(100, item.score * 100))}%` }}
                        ></div>
                      </div>
                      <span className="prediction-score">{(item.score * 100).toFixed(2)}%</span>
                    </div>
                  ))}
                </div>
              </div>
            </div>
          )}
        </section>
      </div>
    </div>
  );
}

export default App;