import React, { useState, useEffect } from 'react';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';
import { Textarea } from '@/components/ui/textarea';
import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select';
import { Switch } from '@/components/ui/switch';
import { Slider } from '@/components/ui/slider';
import { ArrowLeft, Upload, Save } from 'lucide-react';
import '../App.css';

const CreateProject = ({ onBack, onProjectCreated }) => {
  const [formData, setFormData] = useState({
    name: '',
    description: '',
    base_model: '',
    rank: 4,
    alpha: 32,
    dropout: 0.1,
    learning_rate: 0.0001,
    batch_size: 1,
    num_epochs: 10,
    use_8bit_optimizer: true,
    use_gradient_checkpointing: true,
    mixed_precision: 'fp16'
  });

  const [availableModels, setAvailableModels] = useState([]);
  const [loading, setLoading] = useState(false);
  const [datasetFile, setDatasetFile] = useState(null);

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

  const fetchAvailableModels = async () => {
    try {
      const response = await fetch('/api/models');
      const data = await response.json();
      setAvailableModels(data);
    } catch (error) {
      console.error('Erro ao buscar modelos:', error);
    }
  };

  const handleInputChange = (field, value) => {
    setFormData(prev => ({
      ...prev,
      [field]: value
    }));
  };

  const handleFileChange = (event) => {
    const file = event.target.files[0];
    setDatasetFile(file);
  };

  const handleSubmit = async (event) => {
    event.preventDefault();
    setLoading(true);

    try {
      // Create project
      const response = await fetch('/api/projects', {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify(formData),
      });

      if (!response.ok) {
        throw new Error('Erro ao criar projeto');
      }

      const project = await response.json();

      // Upload dataset if provided
      if (datasetFile) {
        const formDataUpload = new FormData();
        formDataUpload.append('dataset', datasetFile);

        const uploadResponse = await fetch(`/api/projects/${project.id}/upload-dataset`, {
          method: 'POST',
          body: formDataUpload,
        });

        if (!uploadResponse.ok) {
          throw new Error('Erro ao fazer upload do dataset');
        }
      }

      onProjectCreated(project);
    } catch (error) {
      console.error('Erro ao criar projeto:', error);
      alert('Erro ao criar projeto: ' + error.message);
    } finally {
      setLoading(false);
    }
  };

  return (
    <div className="space-y-6">
      {/* Header */}
      <div className="flex items-center gap-4">
        <Button variant="outline" onClick={onBack} className="flex items-center gap-2">
          <ArrowLeft className="w-4 h-4" />
          Voltar
        </Button>
        <div>
          <h1 className="text-3xl font-bold">Criar Novo Projeto LoRA</h1>
          <p className="text-gray-600 mt-2">
            Configure os parâmetros para seu novo projeto de treinamento
          </p>
        </div>
      </div>

      <form onSubmit={handleSubmit} className="space-y-6">
        <div className="grid grid-cols-1 lg:grid-cols-2 gap-6">
          {/* Basic Information */}
          <Card>
            <CardHeader>
              <CardTitle>Informações Básicas</CardTitle>
              <CardDescription>
                Configure as informações básicas do seu projeto
              </CardDescription>
            </CardHeader>
            <CardContent className="space-y-4">
              <div>
                <Label htmlFor="name">Nome do Projeto *</Label>
                <Input
                  id="name"
                  value={formData.name}
                  onChange={(e) => handleInputChange('name', e.target.value)}
                  placeholder="Ex: Meu Primeiro LoRA"
                  required
                />
              </div>

              <div>
                <Label htmlFor="description">Descrição</Label>
                <Textarea
                  id="description"
                  value={formData.description}
                  onChange={(e) => handleInputChange('description', e.target.value)}
                  placeholder="Descreva o objetivo do seu projeto..."
                  rows={3}
                />
              </div>

              <div>
                <Label htmlFor="base_model">Modelo Base *</Label>
                <Select
                  value={formData.base_model}
                  onValueChange={(value) => handleInputChange('base_model', value)}
                  required
                >
                  <SelectTrigger>
                    <SelectValue placeholder="Selecione um modelo base" />
                  </SelectTrigger>
                  <SelectContent>
                    {availableModels.map((model) => (
                      <SelectItem key={model.id} value={model.id}>
                        {model.name} ({model.size})
                      </SelectItem>
                    ))}
                  </SelectContent>
                </Select>
              </div>

              <div>
                <Label htmlFor="dataset">Dataset</Label>
                <Input
                  id="dataset"
                  type="file"
                  onChange={handleFileChange}
                  accept=".zip,.tar,.tar.gz"
                  className="cursor-pointer"
                />
                <p className="text-sm text-gray-500 mt-1">
                  Formatos aceitos: ZIP, TAR, TAR.GZ
                </p>
              </div>
            </CardContent>
          </Card>

          {/* LoRA Parameters */}
          <Card>
            <CardHeader>
              <CardTitle>Parâmetros LoRA</CardTitle>
              <CardDescription>
                Configure os parâmetros específicos do LoRA
              </CardDescription>
            </CardHeader>
            <CardContent className="space-y-4">
              <div>
                <Label htmlFor="rank">Rank: {formData.rank}</Label>
                <Slider
                  id="rank"
                  min={1}
                  max={128}
                  step={1}
                  value={[formData.rank]}
                  onValueChange={(value) => handleInputChange('rank', value[0])}
                  className="mt-2"
                />
                <p className="text-sm text-gray-500 mt-1">
                  Menor rank = menos parâmetros, mais eficiente
                </p>
              </div>

              <div>
                <Label htmlFor="alpha">Alpha: {formData.alpha}</Label>
                <Slider
                  id="alpha"
                  min={1}
                  max={128}
                  step={1}
                  value={[formData.alpha]}
                  onValueChange={(value) => handleInputChange('alpha', value[0])}
                  className="mt-2"
                />
                <p className="text-sm text-gray-500 mt-1">
                  Controla a força da adaptação LoRA
                </p>
              </div>

              <div>
                <Label htmlFor="dropout">Dropout: {formData.dropout}</Label>
                <Slider
                  id="dropout"
                  min={0}
                  max={0.5}
                  step={0.01}
                  value={[formData.dropout]}
                  onValueChange={(value) => handleInputChange('dropout', value[0])}
                  className="mt-2"
                />
                <p className="text-sm text-gray-500 mt-1">
                  Previne overfitting durante o treinamento
                </p>
              </div>
            </CardContent>
          </Card>

          {/* Training Parameters */}
          <Card>
            <CardHeader>
              <CardTitle>Parâmetros de Treinamento</CardTitle>
              <CardDescription>
                Configure como o treinamento será executado
              </CardDescription>
            </CardHeader>
            <CardContent className="space-y-4">
              <div>
                <Label htmlFor="learning_rate">Taxa de Aprendizado</Label>
                <Input
                  id="learning_rate"
                  type="number"
                  step="0.00001"
                  value={formData.learning_rate}
                  onChange={(e) => handleInputChange('learning_rate', parseFloat(e.target.value))}
                />
              </div>

              <div>
                <Label htmlFor="batch_size">Tamanho do Batch</Label>
                <Select
                  value={formData.batch_size.toString()}
                  onValueChange={(value) => handleInputChange('batch_size', parseInt(value))}
                >
                  <SelectTrigger>
                    <SelectValue />
                  </SelectTrigger>
                  <SelectContent>
                    <SelectItem value="1">1 (Mais eficiente em memória)</SelectItem>
                    <SelectItem value="2">2</SelectItem>
                    <SelectItem value="4">4</SelectItem>
                    <SelectItem value="8">8</SelectItem>
                  </SelectContent>
                </Select>
              </div>

              <div>
                <Label htmlFor="num_epochs">Número de Épocas: {formData.num_epochs}</Label>
                <Slider
                  id="num_epochs"
                  min={1}
                  max={50}
                  step={1}
                  value={[formData.num_epochs]}
                  onValueChange={(value) => handleInputChange('num_epochs', value[0])}
                  className="mt-2"
                />
              </div>
            </CardContent>
          </Card>

          {/* Optimization Settings */}
          <Card>
            <CardHeader>
              <CardTitle>Otimizações de GPU</CardTitle>
              <CardDescription>
                Configure otimizações para reduzir o uso de GPU
              </CardDescription>
            </CardHeader>
            <CardContent className="space-y-4">
              <div className="flex items-center justify-between">
                <div>
                  <Label htmlFor="use_8bit_optimizer">Otimizador 8-bit</Label>
                  <p className="text-sm text-gray-500">
                    Reduz uso de memória em ~50%
                  </p>
                </div>
                <Switch
                  id="use_8bit_optimizer"
                  checked={formData.use_8bit_optimizer}
                  onCheckedChange={(checked) => handleInputChange('use_8bit_optimizer', checked)}
                />
              </div>

              <div className="flex items-center justify-between">
                <div>
                  <Label htmlFor="use_gradient_checkpointing">Gradient Checkpointing</Label>
                  <p className="text-sm text-gray-500">
                    Troca velocidade por menos memória
                  </p>
                </div>
                <Switch
                  id="use_gradient_checkpointing"
                  checked={formData.use_gradient_checkpointing}
                  onCheckedChange={(checked) => handleInputChange('use_gradient_checkpointing', checked)}
                />
              </div>

              <div>
                <Label htmlFor="mixed_precision">Precisão Mista</Label>
                <Select
                  value={formData.mixed_precision}
                  onValueChange={(value) => handleInputChange('mixed_precision', value)}
                >
                  <SelectTrigger>
                    <SelectValue />
                  </SelectTrigger>
                  <SelectContent>
                    <SelectItem value="fp16">FP16 (Recomendado)</SelectItem>
                    <SelectItem value="bf16">BF16 (Para GPUs mais novas)</SelectItem>
                    <SelectItem value="fp32">FP32 (Sem otimização)</SelectItem>
                  </SelectContent>
                </Select>
              </div>
            </CardContent>
          </Card>
        </div>

        {/* Submit Button */}
        <div className="flex justify-end">
          <Button type="submit" disabled={loading} className="flex items-center gap-2">
            <Save className="w-4 h-4" />
            {loading ? 'Criando...' : 'Criar Projeto'}
          </Button>
        </div>
      </form>
    </div>
  );
};

export default CreateProject;