import 'package:flutter/material.dart';
import 'package:patbond_flutter/core/theme/app_theme.dart';

/// 表单输入框封装（设计规范 §2.2 / §4.1）。
///
/// 密码模式（[obscurable] 为 true）内置可见性切换按钮，点击目标 ≥44×44。
/// 提交中禁用时整体 60% 不透明度。
class AppTextField extends StatefulWidget {
  const AppTextField({
    required this.label,
    super.key,
    this.controller,
    this.prefixIcon,
    this.errorText,
    this.helperText,
    this.enabled = true,
    this.obscurable = false,
    this.keyboardType,
    this.textInputAction,
    this.autofillHints,
    this.onChanged,
    this.onSubmitted,
  });

  final String label;
  final TextEditingController? controller;
  final IconData? prefixIcon;
  final String? errorText;
  final String? helperText;
  final bool enabled;

  /// 是否为密码模式：默认遮蔽输入，并显示可见性切换按钮。
  final bool obscurable;

  final TextInputType? keyboardType;
  final TextInputAction? textInputAction;
  final Iterable<String>? autofillHints;
  final ValueChanged<String>? onChanged;
  final ValueChanged<String>? onSubmitted;

  @override
  State<AppTextField> createState() => _AppTextFieldState();
}

class _AppTextFieldState extends State<AppTextField> {
  bool obscured = true;

  @override
  Widget build(BuildContext context) {
    return Opacity(
      opacity: widget.enabled ? 1 : 0.6,
      child: TextFormField(
        controller: widget.controller,
        enabled: widget.enabled,
        obscureText: widget.obscurable && obscured,
        keyboardType: widget.keyboardType,
        textInputAction: widget.textInputAction,
        autofillHints: widget.autofillHints,
        onChanged: widget.onChanged,
        onFieldSubmitted: widget.onSubmitted,
        decoration: InputDecoration(
          labelText: widget.label,
          errorText: widget.errorText,
          helperText: widget.helperText,
          prefixIcon: widget.prefixIcon == null
              ? null
              : Icon(widget.prefixIcon, color: AppColors.muted),
          suffixIcon: widget.obscurable
              ? IconButton(
                  tooltip: obscured ? '显示密码' : '隐藏密码',
                  constraints: const BoxConstraints(
                    minWidth: 44,
                    minHeight: 44,
                  ),
                  onPressed: widget.enabled
                      ? () => setState(() => obscured = !obscured)
                      : null,
                  icon: Icon(
                    obscured ? Icons.visibility_off : Icons.visibility,
                    color: AppColors.muted,
                  ),
                )
              : null,
        ),
      ),
    );
  }
}