'use client';

import * as React from 'react';
import { Zap, Puzzle, FileCode } from 'lucide-react';
import { Button } from '@/components/ui/button';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Form, FormControl, FormField, FormItem, FormLabel, FormMessage } from '@/components/ui/form';
import { Input } from '@/components/ui/input';
import { Textarea } from '@/components/ui/textarea';
import { useToast } from '@/hooks/use-toast';
import { useForm } from 'react-hook-form';
import { zodResolver } from '@hookform/resolvers/zod';
import { z } from 'zod';
import { Skeleton } from '@/components/ui/skeleton';

/**
 * @fileoverview A placeholder component for a future Plugin Generator feature.
 * This UI allows users to describe a plugin they want to create.
 */

const formSchema = z.object({
  name: z.string().min(3, 'Plugin name must be at least 3 characters.'),
  description: z.string().min(10, 'Description must be at least 10 characters.'),
});

/**
 * A UI component for generating new Apicentric plugins.
 * This is currently a placeholder and does not implement the generation logic.
 * @returns {React.ReactElement} The rendered PluginGenerator component.
 */
export function PluginGenerator() {
  const { toast } = useToast();
  const [isLoading, setIsLoading] = React.useState(false);
  const [generatedCode, setGeneratedCode] = React.useState<string | null>(null);

  const form = useForm<z.infer<typeof formSchema>>({
    resolver: zodResolver(formSchema),
    defaultValues: {
      name: '',
      description: '',
    },
  });

  /**
   * Handles the form submission to generate a plugin.
   * NOTE: This is a placeholder and simulates a network request.
   * @param {z.infer<typeof formSchema>} values - The form values.
   */
  async function onSubmit(values: z.infer<typeof formSchema>) {
    setIsLoading(true);
    setGeneratedCode(null);
    
    // Simulate API call
    await new Promise(resolve => setTimeout(resolve, 1500));
    
    const exampleCode = `
/**
 * @fileoverview A sample plugin for logging requests.
 * This is a placeholder generated by the Apicentric plugin generator.
 */
import { ApicentricError, ApicentricResult } from 'apicentric';
import { Plugin } from 'apicentric/domain';

pub struct ${values.name.replace(/\s+/g, '')}Plugin;

impl Plugin for ${values.name.replace(/\s+/g, '')}Plugin {
    // Implement plugin methods here
}
    `;

    setGeneratedCode(exampleCode);
    setIsLoading(false);
    toast({
      title: 'Plugin Stub Generated',
      description: 'A basic structure for your new plugin has been created.',
    });
  }

  return (
    <div className="grid grid-cols-1 gap-8 lg:grid-cols-2">
      <Card>
        <CardHeader>
          <CardTitle className="flex items-center gap-2">
            <Puzzle className="h-6 w-6 text-primary" />
            <span>Describe Your Plugin</span>
          </CardTitle>
          <CardDescription>
            Provide a name and description for the new plugin you want to create. This will generate a starter template.
          </CardDescription>
        </CardHeader>
        <CardContent>
          <Form {...form}>
            <form onSubmit={form.handleSubmit(onSubmit)} className="space-y-6">
              <FormField
                control={form.control}
                name="name"
                render={({ field }) => (
                  <FormItem>
                    <FormLabel>Plugin Name</FormLabel>
                    <FormControl>
                      <Input placeholder="e.g., 'Request Logger' or 'Auth-Validator'" {...field} />
                    </FormControl>
                    <FormMessage />
                  </FormItem>
                )}
              />
              <FormField
                control={form.control}
                name="description"
                render={({ field }) => (
                  <FormItem>
                    <FormLabel>Plugin Description</FormLabel>
                    <FormControl>
                      <Textarea
                        placeholder="Describe what your plugin will do. For example, 'A plugin to log all incoming requests and their response times.'"
                        className="min-h-[150px] resize-y"
                        {...field}
                      />
                    </FormControl>
                    <FormMessage />
                  </FormItem>
                )}
              />
              <Button type="submit" disabled={isLoading}>
                {isLoading ? 'Generating Stub...' : 'Generate Plugin Stub'}
                <Zap className="ml-2 h-4 w-4" />
              </Button>
            </form>
          </Form>
        </CardContent>
      </Card>
      <Card className="flex flex-col">
        <CardHeader>
          <CardTitle>Generated Plugin Code</CardTitle>
          <CardDescription>
            The generated Rust code for your plugin will appear here.
          </CardDescription>
        </CardHeader>
        <CardContent className="flex-grow">
          <div className="relative h-full min-h-[300px] rounded-md border bg-secondary/30 p-4">
            {isLoading && (
              <div className="space-y-2">
                <Skeleton className="h-4 w-3/4" />
                <Skeleton className="h-4 w-1/2" />
                <Skeleton className="h-4 w-5/6" />
              </div>
            )}
            {!isLoading && !generatedCode && (
              <div className="flex items-center justify-center h-full text-center text-muted-foreground">
                 <FileCode className="mx-auto h-12 w-12" />
                <p className="mt-2">Generated code will be displayed here.</p>
              </div>
            )}
            {generatedCode && (
              <pre className="h-full w-full overflow-auto whitespace-pre-wrap text-sm">
                <code>{generatedCode}</code>
              </pre>
            )}
          </div>
        </CardContent>
      </Card>
    </div>
  );
}
