/**
 * @license
 * Copyright 2025 Qwen Team
 * SPDX-License-Identifier: Apache-2.0
 */

import type React from 'react';
import { forwardRef } from 'react';

/**
 * Input size types
 */
export type InputSize = 'sm' | 'md' | 'lg';

/**
 * Input component props interface
 */
export interface InputProps
  extends Omit<React.InputHTMLAttributes<HTMLInputElement>, 'size'> {
  /** Input size */
  size?: InputSize;
  /** Error state */
  error?: boolean;
  /** Error message to display */
  errorMessage?: string;
  /** Label for the input */
  label?: string;
  /** Helper text below input */
  helperText?: string;
  /** Left icon/element */
  leftElement?: React.ReactNode;
  /** Right icon/element */
  rightElement?: React.ReactNode;
  /** Full width input */
  fullWidth?: boolean;
}

/**
 * Input component with multiple sizes and states
 *
 * @example
 * ```tsx
 * <Input
 *   label="Email"
 *   placeholder="Enter your email"
 *   error={!!errors.email}
 *   errorMessage={errors.email}
 * />
 * ```
 */
const Input = forwardRef<HTMLInputElement, InputProps>(
  (
    {
      size = 'md',
      error = false,
      errorMessage,
      label,
      helperText,
      leftElement,
      rightElement,
      fullWidth = false,
      className = '',
      id,
      disabled,
      ...props
    },
    ref,
  ) => {
    const inputId = id || `input-${Math.random().toString(36).substr(2, 9)}`;

    const baseClasses =
      'border rounded transition-colors focus:outline-none focus:ring-2';

    const sizeClasses: Record<InputSize, string> = {
      sm: 'px-2 py-1 text-sm',
      md: 'px-3 py-2',
      lg: 'px-4 py-3 text-lg',
    };

    const stateClasses = error
      ? 'border-red-500 focus:ring-red-500 focus:border-red-500'
      : 'border-gray-300 focus:ring-blue-500 focus:border-blue-500';

    const disabledClasses = disabled
      ? 'bg-gray-100 cursor-not-allowed opacity-60'
      : 'bg-white';

    const widthClass = fullWidth ? 'w-full' : '';

    const paddingClasses = [
      leftElement ? 'pl-10' : '',
      rightElement ? 'pr-10' : '',
    ].join(' ');

    return (
      <div className={`${fullWidth ? 'w-full' : 'inline-block'}`}>
        {label && (
          <label
            htmlFor={inputId}
            className="block text-sm font-medium text-gray-700 mb-1"
          >
            {label}
          </label>
        )}
        <div className="relative">
          {leftElement && (
            <div className="absolute left-3 top-1/2 -translate-y-1/2 text-gray-500">
              {leftElement}
            </div>
          )}
          <input
            ref={ref}
            id={inputId}
            disabled={disabled}
            aria-invalid={error}
            aria-describedby={
              errorMessage
                ? `${inputId}-error`
                : helperText
                  ? `${inputId}-helper`
                  : undefined
            }
            className={`${baseClasses} ${sizeClasses[size]} ${stateClasses} ${disabledClasses} ${widthClass} ${paddingClasses} ${className}`.trim()}
            {...props}
          />
          {rightElement && (
            <div className="absolute right-3 top-1/2 -translate-y-1/2 text-gray-500">
              {rightElement}
            </div>
          )}
        </div>
        {errorMessage && error && (
          <p id={`${inputId}-error`} className="mt-1 text-sm text-red-600">
            {errorMessage}
          </p>
        )}
        {helperText && !error && (
          <p id={`${inputId}-helper`} className="mt-1 text-sm text-gray-500">
            {helperText}
          </p>
        )}
      </div>
    );
  },
);

Input.displayName = 'Input';

export default Input;