"use client";

import React, { useState, useEffect } from 'react';
import { motion, AnimatePresence } from 'framer-motion';
import { Button } from '@/components/ui/button';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';
import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select';
import { Badge } from '@/components/ui/badge';
import { Dialog, DialogContent, DialogDescription, DialogHeader, DialogTitle } from '@/components/ui/dialog';
import { 
  Plus, 
  Trash2, 
  Bot, 
  AlertCircle, 
  Edit3, 
  Settings2, 
  Eye, 
  EyeOff,
  CheckCircle,
  Clock,
  AlertTriangle,
  RefreshCw,
  Loader2
} from 'lucide-react';
import { useLLMConfigs, CreateLLMConfig, UpdateLLMConfig, LLMConfig } from '@/hooks/use-llm-configs';
import { toast } from 'sonner';
import { Alert, AlertDescription } from '@/components/ui/alert';

const LLM_PROVIDERS = [
  { 
    value: 'OPENAI', 
    label: 'OpenAI', 
    example: 'gpt-4o, gpt-4, gpt-3.5-turbo',
    description: 'Most popular and versatile AI models'
  },
  { 
    value: 'ANTHROPIC', 
    label: 'Anthropic', 
    example: 'claude-3-5-sonnet-20241022, claude-3-opus-20240229',
    description: 'Constitutional AI with strong reasoning'
  },
  { 
    value: 'GROQ', 
    label: 'Groq', 
    example: 'llama3-70b-8192, mixtral-8x7b-32768',
    description: 'Ultra-fast inference speeds'
  },
  { 
    value: 'COHERE', 
    label: 'Cohere', 
    example: 'command-r-plus, command-r',
    description: 'Enterprise-focused language models'
  },
  { 
    value: 'HUGGINGFACE', 
    label: 'HuggingFace', 
    example: 'microsoft/DialoGPT-medium',
    description: 'Open source model hub'
  },
  { 
    value: 'AZURE_OPENAI', 
    label: 'Azure OpenAI', 
    example: 'gpt-4, gpt-35-turbo',
    description: 'Enterprise OpenAI through Azure'
  },
  { 
    value: 'GOOGLE', 
    label: 'Google', 
    example: 'gemini-pro, gemini-pro-vision',
    description: 'Google\'s Gemini AI models'
  },
  { 
    value: 'AWS_BEDROCK', 
    label: 'AWS Bedrock', 
    example: 'anthropic.claude-v2',
    description: 'AWS managed AI service'
  },
  { 
    value: 'OLLAMA', 
    label: 'Ollama', 
    example: 'llama2, codellama',
    description: 'Run models locally'
  },
  { 
    value: 'MISTRAL', 
    label: 'Mistral', 
    example: 'mistral-large-latest, mistral-medium',
    description: 'European AI excellence'
  },
  { 
    value: 'TOGETHER_AI', 
    label: 'Together AI', 
    example: 'togethercomputer/llama-2-70b-chat',
    description: 'Decentralized AI platform'
  },
  { 
    value: 'REPLICATE', 
    label: 'Replicate', 
    example: 'meta/llama-2-70b-chat',
    description: 'Run models via API'
  },
  { 
    value: 'CUSTOM', 
    label: 'Custom Provider', 
    example: 'your-custom-model',
    description: 'Your own model endpoint'
  },
];

export function ModelConfigManager() {
  const { llmConfigs, loading, error, createLLMConfig, updateLLMConfig, deleteLLMConfig, refreshConfigs } = useLLMConfigs();
  const [isAddingNew, setIsAddingNew] = useState(false);
  const [editingConfig, setEditingConfig] = useState<LLMConfig | null>(null);
  const [showApiKey, setShowApiKey] = useState<Record<number, boolean>>({});
  const [formData, setFormData] = useState<CreateLLMConfig>({
    name: '',
    provider: '',
    custom_provider: '',
    model_name: '',
    api_key: '',
    api_base: '',
    litellm_params: {}
  });
  const [isSubmitting, setIsSubmitting] = useState(false);

  // Populate form when editing
  useEffect(() => {
    if (editingConfig) {
      setFormData({
        name: editingConfig.name,
        provider: editingConfig.provider,
        custom_provider: editingConfig.custom_provider || '',
        model_name: editingConfig.model_name,
        api_key: editingConfig.api_key,
        api_base: editingConfig.api_base || '',
        litellm_params: editingConfig.litellm_params || {}
      });
    }
  }, [editingConfig]);

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

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    if (!formData.name || !formData.provider || !formData.model_name || !formData.api_key) {
      toast.error('Please fill in all required fields');
      return;
    }

    setIsSubmitting(true);
    
    let result;
    if (editingConfig) {
      // Update existing config
      result = await updateLLMConfig(editingConfig.id, formData);
    } else {
      // Create new config
      result = await createLLMConfig(formData);
    }
    
    setIsSubmitting(false);

    if (result) {
      setFormData({
        name: '',
        provider: '',
        custom_provider: '',
        model_name: '',
        api_key: '',
        api_base: '',
        litellm_params: {}
      });
      setIsAddingNew(false);
      setEditingConfig(null);
    }
  };

  const handleDelete = async (id: number) => {
    if (confirm('Are you sure you want to delete this configuration? This action cannot be undone.')) {
      await deleteLLMConfig(id);
    }
  };

  const toggleApiKeyVisibility = (configId: number) => {
    setShowApiKey(prev => ({
      ...prev,
      [configId]: !prev[configId]
    }));
  };

  const selectedProvider = LLM_PROVIDERS.find(p => p.value === formData.provider);

  const getProviderInfo = (providerValue: string) => {
    return LLM_PROVIDERS.find(p => p.value === providerValue);
  };

  const maskApiKey = (apiKey: string) => {
    if (apiKey.length <= 8) return '*'.repeat(apiKey.length);
    return apiKey.substring(0, 4) + '*'.repeat(apiKey.length - 8) + apiKey.substring(apiKey.length - 4);
  };

  return (
    <div className="space-y-6">
      {/* Header */}
      <div className="flex flex-col space-y-4 sm:flex-row sm:items-center sm:justify-between sm:space-y-0">
        <div className="space-y-1">
          <div className="flex items-center space-x-3">
            <div className="flex h-10 w-10 items-center justify-center rounded-lg bg-blue-500/10">
              <Settings2 className="h-5 w-5 text-blue-600" />
            </div>
            <div>
              <h2 className="text-2xl font-bold tracking-tight">Model Configurations</h2>
              <p className="text-muted-foreground">
                Manage your LLM provider configurations and API settings.
              </p>
            </div>
          </div>
        </div>
        <div className="flex items-center space-x-2">
          <Button
            variant="outline"
            size="sm"
            onClick={refreshConfigs}
            disabled={loading}
            className="flex items-center gap-2"
          >
            <RefreshCw className={`h-4 w-4 ${loading ? 'animate-spin' : ''}`} />
            Refresh
          </Button>
        </div>
      </div>

      {/* Error Alert */}
      {error && (
        <Alert variant="destructive">
          <AlertCircle className="h-4 w-4" />
          <AlertDescription>
            {error}
          </AlertDescription>
        </Alert>
      )}

      {/* Loading State */}
      {loading && (
        <Card>
          <CardContent className="flex items-center justify-center py-12">
            <div className="flex items-center gap-2 text-muted-foreground">
              <Loader2 className="w-5 h-5 animate-spin" />
              <span>Loading configurations...</span>
            </div>
          </CardContent>
        </Card>
      )}

      {/* Stats Overview */}
      {!loading && !error && (
        <div className="grid gap-4 md:grid-cols-3">
          <Card className="border-l-4 border-l-blue-500">
            <CardContent className="p-6">
              <div className="flex items-center justify-between space-x-4">
                <div className="space-y-1">
                  <p className="text-3xl font-bold tracking-tight">{llmConfigs.length}</p>
                  <p className="text-sm font-medium text-muted-foreground">Total Configurations</p>
                </div>
                <div className="flex h-12 w-12 items-center justify-center rounded-lg bg-blue-500/10">
                  <Bot className="h-6 w-6 text-blue-600" />
                </div>
              </div>
            </CardContent>
          </Card>
          
          <Card className="border-l-4 border-l-green-500">
            <CardContent className="p-6">
              <div className="flex items-center justify-between space-x-4">
                <div className="space-y-1">
                  <p className="text-3xl font-bold tracking-tight">
                    {new Set(llmConfigs.map(c => c.provider)).size}
                  </p>
                  <p className="text-sm font-medium text-muted-foreground">Unique Providers</p>
                </div>
                <div className="flex h-12 w-12 items-center justify-center rounded-lg bg-green-500/10">
                  <CheckCircle className="h-6 w-6 text-green-600" />
                </div>
              </div>
            </CardContent>
          </Card>

          <Card className="border-l-4 border-l-emerald-500">
            <CardContent className="p-6">
              <div className="flex items-center justify-between space-x-4">
                <div className="space-y-1">
                  <p className="text-3xl font-bold tracking-tight text-emerald-600">Active</p>
                  <p className="text-sm font-medium text-muted-foreground">System Status</p>
                </div>
                <div className="flex h-12 w-12 items-center justify-center rounded-lg bg-emerald-500/10">
                  <CheckCircle className="h-6 w-6 text-emerald-600" />
                </div>
              </div>
            </CardContent>
          </Card>
        </div>
      )}

            {/* Configuration Management */}
      {!loading && !error && (
        <div className="space-y-6">
          <div className="flex flex-col space-y-4 sm:flex-row sm:items-center sm:justify-between sm:space-y-0">
            <div>
              <h3 className="text-xl font-semibold tracking-tight">Your Configurations</h3>
              <p className="text-sm text-muted-foreground">
                Manage and configure your LLM providers
              </p>
            </div>
            <Button onClick={() => setIsAddingNew(true)} className="flex items-center gap-2">
              <Plus className="h-4 w-4" />
              Add Configuration
            </Button>
          </div>

        {llmConfigs.length === 0 ? (
          <Card className="border-dashed border-2 border-muted-foreground/25">
            <CardContent className="flex flex-col items-center justify-center py-16 text-center">
              <div className="rounded-full bg-muted p-4 mb-6">
                <Bot className="h-10 w-10 text-muted-foreground" />
              </div>
              <div className="space-y-2 mb-6">
                <h3 className="text-xl font-semibold">No Configurations Yet</h3>
                <p className="text-muted-foreground max-w-sm">
                  Get started by adding your first LLM provider configuration to begin using the system.
                </p>
              </div>
              <Button onClick={() => setIsAddingNew(true)} size="lg">
                <Plus className="h-4 w-4 mr-2" />
                Add First Configuration
              </Button>
            </CardContent>
          </Card>
        ) : (
          <div className="grid gap-4">
            <AnimatePresence>
              {llmConfigs.map((config) => {
                const providerInfo = getProviderInfo(config.provider);
                return (
                  <motion.div
                    key={config.id}
                    initial={{ opacity: 0, y: 10 }}
                    animate={{ opacity: 1, y: 0 }}
                    exit={{ opacity: 0, y: -10 }}
                    transition={{ duration: 0.2 }}
                  >
                    <Card className="group border-l-4 border-l-primary/50 hover:border-l-primary hover:shadow-md transition-all duration-200">
                      <CardContent className="p-6">
                        <div className="flex items-start justify-between">
                          <div className="flex-1 space-y-4">
                            {/* Header */}
                            <div className="flex items-start gap-4">
                              <div className="flex h-12 w-12 items-center justify-center rounded-lg bg-primary/10 group-hover:bg-primary/20 transition-colors">
                                <Bot className="h-6 w-6 text-primary" />
                              </div>
                              <div className="flex-1 space-y-2">
                                <div className="flex items-center gap-3">
                                  <h4 className="text-lg font-semibold tracking-tight">{config.name}</h4>
                                  <Badge variant="secondary" className="text-xs font-medium">
                                    {config.provider}
                                  </Badge>
                                </div>
                                <p className="text-sm text-muted-foreground font-mono">
                                  {config.model_name}
                                </p>
                              </div>
                            </div>

                            {/* Provider Description */}
                            {providerInfo && (
                              <p className="text-sm text-muted-foreground">
                                {providerInfo.description}
                              </p>
                            )}

                            {/* Configuration Details */}
                            <div className="grid gap-4 sm:grid-cols-2">
                              <div className="space-y-2">
                                <Label className="text-xs font-medium uppercase tracking-wide text-muted-foreground">
                                  API Key
                                </Label>
                                <div className="flex items-center space-x-2">
                                  <code className="flex-1 rounded-md bg-muted px-3 py-2 text-xs font-mono">
                                    {showApiKey[config.id] 
                                      ? config.api_key 
                                      : maskApiKey(config.api_key)
                                    }
                                  </code>
                                  <Button
                                    variant="ghost"
                                    size="sm"
                                    onClick={() => toggleApiKeyVisibility(config.id)}
                                    className="h-8 w-8 p-0"
                                  >
                                    {showApiKey[config.id] ? (
                                      <EyeOff className="h-3 w-3" />
                                    ) : (
                                      <Eye className="h-3 w-3" />
                                    )}
                                  </Button>
                                </div>
                              </div>

                              {config.api_base && (
                                <div className="space-y-2">
                                  <Label className="text-xs font-medium uppercase tracking-wide text-muted-foreground">
                                    API Base URL
                                  </Label>
                                  <code className="block rounded-md bg-muted px-3 py-2 text-xs font-mono break-all">
                                    {config.api_base}
                                  </code>
                                </div>
                              )}
                            </div>

                            {/* Metadata */}
                            <div className="flex flex-wrap items-center gap-4 pt-4 border-t border-border/50">
                              <div className="flex items-center gap-2 text-xs text-muted-foreground">
                                <Clock className="h-3 w-3" />
                                <span>Created {new Date(config.created_at).toLocaleDateString()}</span>
                              </div>
                              <div className="flex items-center gap-2 text-xs">
                                <div className="h-2 w-2 rounded-full bg-green-500"></div>
                                <span className="text-green-600 font-medium">Active</span>
                              </div>
                            </div>
                          </div>

                          {/* Actions */}
                          <div className="flex flex-col gap-2 ml-6">
                            <Button
                              variant="outline"
                              size="sm"
                              onClick={() => setEditingConfig(config)}
                              className="h-8 w-8 p-0"
                            >
                              <Edit3 className="h-4 w-4" />
                            </Button>
                            <Button
                              variant="outline"
                              size="sm"
                              onClick={() => handleDelete(config.id)}
                              className="h-8 w-8 p-0 border-destructive/20 text-destructive hover:bg-destructive hover:text-destructive-foreground"
                            >
                              <Trash2 className="h-4 w-4" />
                            </Button>
                          </div>
                        </div>
                      </CardContent>
                    </Card>
                  </motion.div>
                );
              })}
            </AnimatePresence>
          </div>
        )}
      </div>
      )}

      {/* Add/Edit Configuration Dialog */}
      <Dialog open={isAddingNew || !!editingConfig} onOpenChange={(open) => {
        if (!open) {
          setIsAddingNew(false);
          setEditingConfig(null);
          setFormData({
            name: '',
            provider: '',
            custom_provider: '',
            model_name: '',
            api_key: '',
            api_base: '',
            litellm_params: {}
          });
        }
      }}>
        <DialogContent className="max-w-2xl max-h-[90vh] overflow-y-auto">
          <DialogHeader>
            <DialogTitle className="flex items-center gap-2">
              {editingConfig ? <Edit3 className="w-5 h-5" /> : <Plus className="w-5 h-5" />}
              {editingConfig ? 'Edit LLM Configuration' : 'Add New LLM Configuration'}
            </DialogTitle>
            <DialogDescription>
              {editingConfig 
                ? 'Update your language model provider configuration'
                : 'Configure a new language model provider for your AI assistant'
              }
            </DialogDescription>
          </DialogHeader>

          <form onSubmit={handleSubmit} className="space-y-4">
            <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
              <div className="space-y-2">
                <Label htmlFor="name">Configuration Name *</Label>
                <Input
                  id="name"
                  placeholder="e.g., My OpenAI GPT-4"
                  value={formData.name}
                  onChange={(e) => handleInputChange('name', e.target.value)}
                  required
                />
              </div>

              <div className="space-y-2">
                <Label htmlFor="provider">Provider *</Label>
                <Select value={formData.provider} onValueChange={(value) => handleInputChange('provider', value)}>
                  <SelectTrigger className="h-auto min-h-[2.5rem] py-2">
                    <SelectValue placeholder="Select a provider">
                      {formData.provider && (
                        <div className="flex items-center space-x-2 py-1">
                          <div className="font-medium">
                            {LLM_PROVIDERS.find(p => p.value === formData.provider)?.label}
                          </div>
                          <div className="text-xs text-muted-foreground">
                            •
                          </div>
                          <div className="text-xs text-muted-foreground">
                            {LLM_PROVIDERS.find(p => p.value === formData.provider)?.description}
                          </div>
                        </div>
                      )}
                    </SelectValue>
                  </SelectTrigger>
                  <SelectContent>
                    {LLM_PROVIDERS.map((provider) => (
                      <SelectItem key={provider.value} value={provider.value}>
                        <div className="space-y-1 py-1">
                          <div className="font-medium">{provider.label}</div>
                          <div className="text-xs text-muted-foreground">
                            {provider.description}
                          </div>
                        </div>
                      </SelectItem>
                    ))}
                  </SelectContent>
                </Select>
              </div>
            </div>

            {formData.provider === 'CUSTOM' && (
              <div className="space-y-2">
                <Label htmlFor="custom_provider">Custom Provider Name *</Label>
                <Input
                  id="custom_provider"
                  placeholder="e.g., my-custom-provider"
                  value={formData.custom_provider}
                  onChange={(e) => handleInputChange('custom_provider', e.target.value)}
                  required
                />
              </div>
            )}

            <div className="space-y-2">
              <Label htmlFor="model_name">Model Name *</Label>
              <Input
                id="model_name"
                placeholder={selectedProvider?.example || "e.g., gpt-4"}
                value={formData.model_name}
                onChange={(e) => handleInputChange('model_name', e.target.value)}
                required
              />
              {selectedProvider && (
                <p className="text-xs text-muted-foreground">
                  Examples: {selectedProvider.example}
                </p>
              )}
            </div>

            <div className="space-y-2">
              <Label htmlFor="api_key">API Key *</Label>
              <Input
                id="api_key"
                type="password"
                placeholder="Your API key"
                value={formData.api_key}
                onChange={(e) => handleInputChange('api_key', e.target.value)}
                required
              />
            </div>

            <div className="space-y-2">
              <Label htmlFor="api_base">API Base URL (Optional)</Label>
              <Input
                id="api_base"
                placeholder="e.g., https://api.openai.com/v1"
                value={formData.api_base}
                onChange={(e) => handleInputChange('api_base', e.target.value)}
              />
            </div>

            <div className="flex gap-2 pt-4">
              <Button type="submit" disabled={isSubmitting}>
                {isSubmitting 
                  ? (editingConfig ? 'Updating...' : 'Adding...') 
                  : (editingConfig ? 'Update Configuration' : 'Add Configuration')
                }
              </Button>
              <Button
                type="button"
                variant="outline"
                onClick={() => {
                  setIsAddingNew(false);
                  setEditingConfig(null);
                  setFormData({
                    name: '',
                    provider: '',
                    custom_provider: '',
                    model_name: '',
                    api_key: '',
                    api_base: '',
                    litellm_params: {}
                  });
                }}
                disabled={isSubmitting}
              >
                Cancel
              </Button>
            </div>
          </form>
        </DialogContent>
      </Dialog>
    </div>
  );
}