import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:qpay/screens/pay/pay_controller.dart';
import 'package:skeletonizer/skeletonizer.dart';

class PayScreen extends StatefulWidget {
  const PayScreen({super.key});

  @override
  State<PayScreen> createState() => _PayScreenState();
}

class _PayScreenState extends State<PayScreen> with TickerProviderStateMixin {
  late AnimationController _controller;
  late Animation<double> _fadeAnimation;
  late Animation<Offset> _slideAnimation;

  final _formKey = GlobalKey<FormState>();
  final _amountController = TextEditingController();
  final _descriptionController = TextEditingController();
  String _selectedBillType = '';

  @override
  void initState() {
    super.initState();

    _controller = AnimationController(
      vsync: this,
      duration: const Duration(milliseconds: 800),
    );

    _fadeAnimation = Tween<double>(begin: 0.0, end: 1.0).animate(
      CurvedAnimation(
        parent: _controller,
        curve: const Interval(0.0, 0.5, curve: Curves.easeOut),
      ),
    );

    _slideAnimation = Tween<Offset>(
      begin: const Offset(0, 0.1),
      end: Offset.zero,
    ).animate(
      CurvedAnimation(
        parent: _controller,
        curve: const Interval(0.0, 0.5, curve: Curves.easeOut),
      ),
    );

    _controller.forward();
  }

  @override
  void dispose() {
    _controller.dispose();
    _amountController.dispose();
    _descriptionController.dispose();
    super.dispose();
  }

  void _showErrorSnackBar(String? message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(message.toString()),
        behavior: SnackBarBehavior.floating,
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text(
          'Make Payment',
          style: TextStyle(color: Colors.black87),
        ),
      ),
      body: Consumer<PayController>(
        builder: (context, controller, child) {
          if (controller.model.errorMessage != null) {
            WidgetsBinding.instance.addPostFrameCallback((_) {
              _showErrorSnackBar(controller.model.errorMessage);
            });
          }
          return SingleChildScrollView(
            child: Padding(
              padding: const EdgeInsets.all(16.0),
              child: FadeTransition(
                opacity: _fadeAnimation,
                child: SlideTransition(
                  position: _slideAnimation,
                  child: Form(
                    key: _formKey,
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        SizedBox(height: 20),
                        _buildBillProductSelector(controller),
                        const SizedBox(height: 24),
                        _buildAmountField(),
                        const SizedBox(height: 24),
                        _buildDescriptionField(),
                        const SizedBox(height: 32),
                        _buildPayButton(),
                      ],
                    ),
                  ),
                ),
              ),
            ),
          );
        },
      ),
    );
  }

  Widget _buildBillProductSelector(PayController controller) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        const Text(
          'Select Provider Product',
          style: TextStyle(fontSize: 16, fontWeight: FontWeight.w500),
        ),
        const SizedBox(height: 12),
        Container(
          padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 4),
          decoration: BoxDecoration(
            color: Theme.of(context).colorScheme.surface,
            borderRadius: BorderRadius.circular(12),
            border: Border.all(
              color: Theme.of(context).colorScheme.primary.withOpacity(0.2),
            ),
          ),
          child: DropdownButtonHideUnderline(
            child: DropdownButton<String>(
              isExpanded: true,
              icon: const Icon(Icons.arrow_drop_down),
              items: [
                ...controller.model.products.map(
                  (e) => DropdownMenuItem<String>(
                    value: e.uid,
                    child: Text(e.displayName),
                  ),
                ),
              ],
              onChanged: (String? newValue) {
                if (newValue != null) {
                  setState(() {
                    _selectedBillType = newValue;
                  });
                }
              },
            ),
          ),
        ),
      ],
    );
  }

  Widget _buildAmountField() {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        const Text(
          'Amount',
          style: TextStyle(fontSize: 16, fontWeight: FontWeight.w500),
        ),
        const SizedBox(height: 12),
        TextFormField(
          controller: _amountController,
          keyboardType: TextInputType.number,
          decoration: const InputDecoration(
            prefixIcon: Icon(Icons.attach_money),
            hintText: 'Enter amount',
          ),
          validator: (value) {
            if (value == null || value.isEmpty) {
              return 'Please enter an amount';
            }
            if (double.tryParse(value) == null) {
              return 'Please enter a valid amount';
            }
            return null;
          },
        ),
      ],
    );
  }

  Widget _buildDescriptionField() {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        const Text(
          'Description',
          style: TextStyle(fontSize: 16, fontWeight: FontWeight.w500),
        ),
        const SizedBox(height: 12),
        TextFormField(
          controller: _descriptionController,
          maxLines: 3,
          decoration: const InputDecoration(
            hintText: 'Enter description (optional)',
            alignLabelWithHint: true,
          ),
        ),
      ],
    );
  }

  Widget _buildPayButton() {
    return SizedBox(
      width: double.infinity,
      child: ElevatedButton(
        onPressed: () {
          if (_formKey.currentState!.validate()) {
            // TODO: Implement payment logic
            ScaffoldMessenger.of(context).showSnackBar(
              const SnackBar(
                content: Text('Payment processed successfully!'),
                backgroundColor: Colors.green,
              ),
            );
          }
        },
        style: ElevatedButton.styleFrom(
          padding: const EdgeInsets.symmetric(vertical: 16),
        ),
        child: const Text(
          'Pay Now',
          style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold),
        ),
      ),
    );
  }
}