/**
 * FormRadio Component
 * 
 * A reusable radio button component that handles:
 * - Radio button groups
 * - Label
 * - Controller (react-hook-form)
 * - Error handling
 * 
 * This component reduces code duplication for radio button fields across forms.
 */

import React from 'react';
import { Control, Controller, FieldError, FieldPath, FieldValues } from 'react-hook-form';
import { Label } from '@/components/ui/label';
import { RadioGroup, RadioGroupItem } from '@/components/ui/radio-group';
import { cn } from '@/lib/utils';

// =============================================================================
// TYPES
// =============================================================================

export interface RadioOption {
  value: string | number;
  label: string;
  disabled?: boolean;
}

export interface FormRadioProps<
  TFieldValues extends FieldValues = FieldValues,
  TName extends FieldPath<TFieldValues> = FieldPath<TFieldValues>
> {
  // Form control
  control: Control<TFieldValues>;
  name: TName;
  
  // Field configuration
  label?: string;
  required?: boolean;
  
  // Radio configuration
  options: RadioOption[];
  
  // Styling
  className?: string;
  labelClassName?: string;
  radioClassName?: string;
  errorClassName?: string;
  groupClassName?: string;
  
  // Layout
  layout?: 'horizontal' | 'vertical';
  columns?: number; // For grid layout
  
  // Validation
  validation?: {
    required?: boolean | string;
  };
  
  // Additional props
  disabled?: boolean;
  size?: 'sm' | 'md' | 'lg';
  
  // Custom render functions
  renderOption?: (option: RadioOption, checked: boolean, onChange: (value: string) => void) => React.ReactElement;
}

// =============================================================================
// COMPONENT
// =============================================================================

export function FormRadio<
  TFieldValues extends FieldValues = FieldValues,
  TName extends FieldPath<TFieldValues> = FieldPath<TFieldValues>
>({
  control,
  name,
  label,
  required = false,
  options,
  className = '',
  labelClassName = '',
  radioClassName = '',
  errorClassName = '',
  groupClassName = '',
  layout = 'horizontal',
  columns = 1,
  validation,
  disabled = false,
  size = 'md',
  renderOption,
}: FormRadioProps<TFieldValues, TName>) {
  
  // =============================================================================
  // HELPER FUNCTIONS
  // =============================================================================
  
  const getRadioSize = (size: 'sm' | 'md' | 'lg') => {
    switch (size) {
      case 'sm':
        return 'h-4 w-4';
      case 'lg':
        return 'h-6 w-6';
      default:
        return 'h-5 w-5';
    }
  };
  
  const getGroupLayout = () => {
    if (layout === 'vertical') {
      return 'flex flex-col gap-2';
    }
    
    if (columns > 1) {
      return `grid grid-cols-${columns} gap-2`;
    }
    
    return 'flex flex-wrap gap-3';
  };
  
  // =============================================================================
  // RENDER FUNCTIONS
  // =============================================================================
  
  const renderDefaultOption = (option: RadioOption, checked: boolean, onChange: (value: string) => void) => {
    if (renderOption) {
      return renderOption(option, checked, onChange);
    }
    
    return (
      <div key={option.value} className="flex items-center space-x-2">
        <RadioGroupItem
          value={String(option.value)}
          id={`${name}-${option.value}`}
          disabled={disabled || option.disabled}
          className={cn(getRadioSize(size), radioClassName)}
        />
        <Label
          htmlFor={`${name}-${option.value}`}
          className={cn(
            'text-sm font-medium leading-none peer-disabled:cursor-not-allowed peer-disabled:opacity-70',
            labelClassName
          )}
        >
          {option.label}
        </Label>
      </div>
    );
  };
  
  // =============================================================================
  // MAIN RENDER
  // =============================================================================
  
  return (
    <div className={cn('space-y-2', className)}>
      {/* Group Label */}
      {label && (
        <Label 
          className={cn(
            'text-sm font-medium leading-none peer-disabled:cursor-not-allowed peer-disabled:opacity-70',
            required && 'after:content-["*"] after:ml-0.5 after:text-destructive',
            labelClassName
          )}
        >
          {label}
        </Label>
      )}
      
      {/* Controller */}
      <Controller
        control={control}
        name={name}
        rules={{
          required: validation?.required || required,
        }}
        render={({ field, fieldState }) => (
          <div className="space-y-1">
            <RadioGroup
              value={field.value}
              onValueChange={field.onChange}
              disabled={disabled}
              className={cn(getGroupLayout(), groupClassName)}
            >
              {options.map((option) => 
                renderDefaultOption(
                  option, 
                  field.value === String(option.value),
                  field.onChange
                )
              )}
            </RadioGroup>
            
            {/* Error Message */}
            {fieldState.error && (
              <p className={cn(
                'text-sm text-destructive',
                errorClassName
              )}>
                {fieldState.error.message}
              </p>
            )}
          </div>
        )}
      />
    </div>
  );
}

export default FormRadio;