import 'package:cw_core/currency.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

class FloatingAmountInput extends StatefulWidget {
  const FloatingAmountInput(
      {super.key,
      required this.currency,
      required this.controller,
      this.focusNode,
      this.inputFormatters,
      this.onChanged,
      this.validator});

  final Currency currency;
  final TextEditingController controller;
  final FocusNode? focusNode;
  final List<TextInputFormatter>? inputFormatters;
  final Function(String)? onChanged;
  final FormFieldValidator<String>? validator;

  @override
  State<FloatingAmountInput> createState() => _FloatingAmountInputState();
}

class _FloatingAmountInputState extends State<FloatingAmountInput> {
  bool _amountFocused = false;
  late FocusNode focusNode = widget.focusNode ?? FocusNode();

  @override
  void initState() {
    super.initState();
    focusNode.addListener(() => setState(() => _amountFocused = focusNode.hasFocus));
  }

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Row(
        mainAxisSize: MainAxisSize.min,
        crossAxisAlignment: CrossAxisAlignment.baseline,
        textBaseline: TextBaseline.alphabetic,
        children: [
          IntrinsicWidth(
            child: TextFormField(
              controller: widget.controller,
              focusNode: focusNode,
              maxLines: 1,
              onChanged: widget.onChanged,
              autovalidateMode: AutovalidateMode.always,
              validator: widget.validator,
              keyboardType: TextInputType.numberWithOptions(
                signed: false,
                decimal: true,
              ),
              inputFormatters: <TextInputFormatter>[
                FilteringTextInputFormatter.allow(
                  RegExp(r'^\d*[.,]?\d*$'),
                ),
              ],
              decoration: InputDecoration(
                isDense: true,
                isCollapsed: true,
                contentPadding: EdgeInsets.zero,
                fillColor: Colors.transparent,
                hoverColor: Colors.transparent,
                focusedBorder: InputBorder.none,
                enabledBorder: InputBorder.none,
                hintText: _amountFocused || widget.controller.text.isNotEmpty ? null : "0.00",
                hintStyle: Theme.of(context).textTheme.displayMedium?.copyWith(
                      fontWeight: FontWeight.w400,
                      color: Theme.of(context).colorScheme.onSurfaceVariant,
                    ),
              ),
              style: Theme.of(context).textTheme.displayMedium?.copyWith(
                    fontWeight: FontWeight.w400,
                    fontSize: 45,
                    color: Theme.of(context).colorScheme.onSurface,
                  ),
            ),
          ),
          const SizedBox(width: 8),
          Text(
            widget.currency.symbol,
            maxLines: 1,
            overflow: TextOverflow.ellipsis,
            style: Theme.of(context).textTheme.displayMedium?.copyWith(
                  fontWeight: FontWeight.w400,
                  fontSize: 45,
                  color: Theme.of(context).colorScheme.onSurfaceVariant,
                ),
          ),
        ],
      ),
    );
  }
}