import 'package:flisp_app/provider/todo_provider.dart';
import 'package:flutter/material.dart';
import 'package:flutter_form_builder/flutter_form_builder.dart';
import 'package:provider/provider.dart';
import 'package:flisp_app/models/todo.dart';
import 'package:flisp_app/utils/date_utils.dart';

class TodoForm extends StatefulWidget {
  final GlobalKey<FormBuilderState> formKey;
  final bool isEditing;
  final Todo? initialTodo;

  const TodoForm({
    super.key,
    required this.formKey,
    required this.isEditing,
    this.initialTodo,
  });

  @override
  State<TodoForm> createState() => _TodoFormState();
}

class _TodoFormState extends State<TodoForm> {
  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    final int maxTitleCount = 10;
    final int maxContentCount = 20;
    final store = Provider.of<TodoProvider>(context);

    Widget buildTitle() {
      return Row(
        children: [
          Icon(
            widget.isEditing ? Icons.edit_note : Icons.add_task,
            color: Colors.orange,
            size: 24,
          ),
          SizedBox(width: 8),
          Text(
            widget.isEditing ? '编辑待办事项' : '添加待办事项',
            style: TextStyle(
              fontSize: 20,
              fontWeight: FontWeight.bold,
              color: Colors.orange,
            ),
          ),
        ],
      );
    }

    FormBuilderTextField buildTitleField() {
      return FormBuilderTextField(
        name: 'title',
        initialValue: store.formItem.title,
        onChanged: (value) {
          setState(() {
            store.formItem.title = value ?? '';
          });
        },
        decoration: InputDecoration(
          labelText: '标题',
          hintText: '请输入待办事项标题...',
          counterText: '',
          suffixText: '${store.formItem.title.length}/$maxTitleCount',
          border: OutlineInputBorder(
            borderRadius: BorderRadius.circular(12),
            borderSide: BorderSide(color: Colors.grey.shade200),
          ),
          enabledBorder: OutlineInputBorder(
            borderRadius: BorderRadius.circular(12),
            borderSide: BorderSide(color: Colors.grey.shade200),
          ),
          focusedBorder: OutlineInputBorder(
            borderRadius: BorderRadius.circular(12),
            borderSide: BorderSide(color: Colors.orange),
          ),
          filled: true,
          fillColor: Colors.white,
          prefixIcon: Icon(Icons.title, color: Colors.blue),
          contentPadding: EdgeInsets.symmetric(horizontal: 16, vertical: 14),
        ),
        maxLength: maxTitleCount,
        validator: (value) {
          if (value == null || value.isEmpty) {
            return '请输入标题';
          }
          if (value.length > maxTitleCount) {
            return '标题不能超过$maxTitleCount个字符';
          }
          return null;
        },
      );
    }

    FormBuilderTextField buildDescriptionField() {
      return FormBuilderTextField(
        name: 'description',
        initialValue: store.formItem.content,
        onChanged: (value) {
          setState(() {
            store.formItem.content = value ?? '';
          });
        },
        decoration: InputDecoration(
          labelText: '内容',
          hintText: '请输入待办事项内容...',
          counterText: '',
          suffixText: '${store.formItem.content.length}/$maxContentCount',
          border: OutlineInputBorder(
            borderRadius: BorderRadius.circular(12),
            borderSide: BorderSide(color: Colors.grey.shade200),
          ),
          enabledBorder: OutlineInputBorder(
            borderRadius: BorderRadius.circular(12),
            borderSide: BorderSide(color: Colors.grey.shade200),
          ),
          focusedBorder: OutlineInputBorder(
            borderRadius: BorderRadius.circular(12),
            borderSide: BorderSide(color: Colors.orange),
          ),
          filled: true,
          fillColor: Colors.white,
          prefixIcon: Icon(Icons.description, color: Colors.green),
          contentPadding: EdgeInsets.symmetric(horizontal: 16, vertical: 14),
        ),
        maxLines: 2,
        maxLength: maxContentCount,
        validator: (value) {
          if (value != null && value.length > maxContentCount) {
            return '内容不能超过$maxContentCount个字符';
          }
          return null;
        },
      );
    }

    IconButton buildClearDateSuffixIcon() {
      return IconButton(
        icon: Icon(Icons.clear, size: 18),
        onPressed: () {
          setState(() {
            store.formItem.dueDate = null;
          });
          widget.formKey.currentState?.fields['dueDate']?.didChange(null);
        },
      );
    }

    FormBuilderDateTimePicker buildDateField() {
      return FormBuilderDateTimePicker(
        name: 'dueDate',
        initialValue: store.formItem.dueDate,
        inputType: InputType.date,
        onChanged: (value) {
          setState(() {
            store.formItem.dueDate = value;
          });
        },
        decoration: InputDecoration(
          labelText:
              store.formItem.dueDate == null
                  ? '选择截止日期'
                  : '截止: ${formatDate(store.formItem.dueDate!)}',
          labelStyle: TextStyle(
            color:
                store.formItem.dueDate == null ? Colors.grey : Colors.black87,
          ),
          prefixIcon: Icon(Icons.calendar_today, color: Colors.purple),
          border: OutlineInputBorder(
            borderRadius: BorderRadius.circular(12),
            borderSide: BorderSide(color: Colors.grey.shade200),
          ),
          enabledBorder: OutlineInputBorder(
            borderRadius: BorderRadius.circular(12),
            borderSide: BorderSide(color: Colors.grey.shade200),
          ),
          focusedBorder: OutlineInputBorder(
            borderRadius: BorderRadius.circular(12),
            borderSide: BorderSide(color: Colors.orange),
          ),
          filled: true,
          fillColor: Colors.white,
          contentPadding: EdgeInsets.symmetric(horizontal: 16, vertical: 14),
          suffixIcon:
              store.formItem.dueDate != null
                  ? buildClearDateSuffixIcon()
                  : null,
        ),
        validator: (value) {
          if (value != null &&
              value.isBefore(DateTime.now().subtract(Duration(days: 1)))) {
            return '不能选择过去的日期';
          }
          return null;
        },
      );
    }

    FormBuilderRadioGroup builderRadioGroup() {
      return FormBuilderRadioGroup<TodoPriority>(
        name: 'priority',
        initialValue: store.formItem.priority,
        decoration: InputDecoration(
          border: InputBorder.none,
          contentPadding: EdgeInsets.zero,
        ),
        orientation: OptionsOrientation.horizontal,
        wrapSpacing: 6,
        options:
            TodoPriority.values.map((priority) {
              return FormBuilderFieldOption<TodoPriority>(
                value: priority,
                child: Row(
                  mainAxisSize: MainAxisSize.min,
                  children: [Text(priority.label)],
                ),
              );
            }).toList(),
        onChanged: (value) {
          if (value != null) {
            setState(() {
              store.formItem.priority = value;
            });
          }
        },
      );
    }

    Container buildPriorityField() {
      return Container(
        decoration: BoxDecoration(
          color: Colors.white,
          borderRadius: BorderRadius.circular(12),
          border: Border.all(color: Colors.grey.shade300, width: 1),
        ),
        padding: EdgeInsets.all(12),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                Icon(Icons.flag, color: Colors.orange),
                SizedBox(width: 6),
                Text('优先级'),
              ],
            ),
            builderRadioGroup(),
          ],
        ),
      );
    }

    FormBuilder buildForm() {
      return FormBuilder(
        key: widget.formKey,
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            buildTitleField(),
            SizedBox(height: 12),
            buildDescriptionField(),
            SizedBox(height: 12),
            buildDateField(),
            SizedBox(height: 12),
            buildPriorityField(),
          ],
        ),
      );
    }

    return Padding(
      padding: const EdgeInsets.all(16),
      child: Column(
        mainAxisSize: MainAxisSize.min,
        children: [buildTitle(), SizedBox(height: 20), buildForm()],
      ),
    );
  }
}