import 'package:flutter/material.dart';

import '/common/constants.dart';
import '/request/signup_signin.dart';

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

  final Color color;
  final bool obscureText;
  final String type;
  final bool isSignup;
  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;
  FocusNode? _node;

  @override
  void initState() {
    super.initState();
    if (widget.isSignup) {
      _node = FocusNode();
      _node!.addListener(_handleFocusChange);
    }
  }

  void _handleFocusChange() async {
    if (!widget.isSignup) {
      return;
    }

    switch (widget.type) {
      case 'username' || 'email':
        if (!_node!.hasFocus) {
          if (widget.controller.text.isNotEmpty && _errorText == null) {
            Map<String, dynamic> res =
                await hasAccountExisted(widget.type, widget.controller.text);
            if (widget.type == 'username') {
              setState(() {
                res['code'] == 10100
                    ? _errorText = null
                    : _errorText = '用户名已存在';
              });
            } else {
              setState(() {
                res['code'] == 10100
                    ? _errorText = null
                    : _errorText = '邮箱已被使用';
              });
            }
          }
        }

      default:
        null;
    }
  }

  @override
  void dispose() {
    if (widget.isSignup) {
      _node!.removeListener(_handleFocusChange);
      _node!.dispose();
    }
    super.dispose();
  }

  @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,
      focusNode: _node,
      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':
        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;
          });
        }
    }
  }
}

class CommonTextField extends StatelessWidget {
  const CommonTextField({
    super.key,
    this.color = kPrimaryColor,
    this.obscureText = false,
    required this.labelText,
    required this.controller,
  });

  final Color color;
  final bool obscureText;
  final String labelText;
  final TextEditingController controller;

  @override
  Widget build(BuildContext context) {
    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))),
    );
  }
}

class CommonElevatedButton extends StatelessWidget {
  const CommonElevatedButton({
    super.key,
    required this.onPressed,
    required this.text,
    this.color = kPrimaryColor,
  });

  final VoidCallback onPressed;
  final String text;
  final Color color;

  @override
  Widget build(BuildContext context) {
    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,
          color: kContentColorDark,
        ),
      ),
    );
  }
}