import 'package:flutter/material.dart';

import 'package:together_mobile/common/constants.dart';

class SignTextField extends StatefulWidget {
  const SignTextField({
    super.key,
    this.color = kPrimaryColor,
    this.obscureText = false,
    required this.type,
    required this.labelText,
    required this.controller,
    required this.isError,
  });

  final Color color;
  final bool obscureText;
  final String type;
  final String labelText;
  final TextEditingController controller;
  final void Function(String, bool) isError;

  @override
  State<SignTextField> createState() => _SignTextFieldState();
}

class _SignTextFieldState extends State<SignTextField> {
  int _length = 0;
  String? _errorText;

  @override
  Widget build(BuildContext context) {
    return TextField(
      onChanged: (String newValue) {
        setState(() {
          _length = newValue.characters.length;
        });
        setErrorText();
        widget.isError(
            widget.type,
            (_errorText == null && widget.controller.text.isEmpty) ||
                _errorText != null);
      },
      controller: widget.controller,
      obscureText: widget.obscureText,
      cursorColor: widget.color,
      textAlignVertical: TextAlignVertical.bottom,
      keyboardType: initTextInputType(),
      decoration: InputDecoration(
        errorText: _errorText,
        labelText: widget.labelText,
        counterText: '$_length 字符',
        floatingLabelStyle: TextStyle(color: widget.color),
        focusedBorder: UnderlineInputBorder(
          borderSide: BorderSide(color: widget.color),
        ),
      ),
    );
  }

  TextInputType initTextInputType() {
    switch (widget.type) {
      case 'email':
        return TextInputType.emailAddress;
      case 'code':
        return TextInputType.number;
      case _:
        return TextInputType.visiblePassword;
    }
  }

  void setErrorText() {
    if (widget.controller.text.isEmpty) {
      setState(() {
        _errorText = null;
      });
    }

    switch (widget.type) {
      case 'username':
        if (widget.controller.text.contains(RegExp(r'\W+'))) {
          setState(() {
            _errorText = '用户名只允许字母, 数字和下划线';
          });
        } else if (_length < 5 || _length > 20) {
          setState(() {
            _errorText = '用户名需为8-20个字符';
          });
        } else {
          setState(() {
            _errorText = null;
          });
        }
        break;

      case 'password' || 'password1' || 'password2':
        if (widget.controller.text.contains(RegExp(r'\s'))) {
          setState(() {
            _errorText = '密码不能包含空格';
          });
        } else if (_length < 8 || _length > 30) {
          setState(() {
            _errorText = '密码需为8-30个字符';
          });
        } else {
          setState(() {
            _errorText = null;
          });
        }
        break;

      case 'email':
        var exp = RegExp(
            r'^[a-zA-Z0-9_.-]+@[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)*\.[a-zA-Z0-9]{2,6}$');
        if (!exp.hasMatch(widget.controller.text)) {
          setState(() {
            _errorText = '邮箱格式错误';
          });
        } else {
          setState(() {
            _errorText = null;
          });
        }

      case 'code':
        if (!RegExp(r'\d{6}').hasMatch(widget.controller.text)) {
          setState(() {
            _errorText = '6为数字';
          });
        } else if (widget.controller.text.characters.length != 6) {
          _errorText = '6位数字';
        } else {
          setState(() {
            _errorText = null;
          });
        }
    }
  }
}

TextField textField({
  Color color = kPrimaryColor,
  bool obscureText = false,
  required String labelText,
  required TextEditingController controller,
}) {
  return TextField(
    controller: controller,
    obscureText: obscureText,
    cursorColor: kSecondaryColor,
    textAlignVertical: TextAlignVertical.bottom,
    decoration: InputDecoration(
        helperText: '5-10位',
        errorText: 'xxx',
        labelText: labelText,
        floatingLabelStyle: const TextStyle(color: kSecondaryColor),
        focusedBorder:
            UnderlineInputBorder(borderSide: BorderSide(color: color))),
  );
}

ElevatedButton elevatedButton(
    {required VoidCallback onPressed,
    required String text,
    Color? color = kPrimaryColor}) {
  return ElevatedButton(
    onPressed: onPressed,
    style: ElevatedButton.styleFrom(
        backgroundColor: color,
        elevation: 0,
        fixedSize: const Size(150, 20),
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12))),
    child: Text(
      text,
      style: const TextStyle(fontSize: 20.0, letterSpacing: 10),
    ),
  );
}