import 'dart:io';
import 'package:business_panel/core/config/app_colors.dart';
import 'package:business_panel/domain/entities/discount_type_entity.dart';
import 'package:business_panel/gen/assets.gen.dart';
import 'package:business_panel/presentation/discount/bloc/discount_bloc.dart';
import 'package:business_panel/presentation/discount/bloc/discount_event.dart';
import 'package:business_panel/presentation/discount/bloc/discount_state.dart';
import 'package:business_panel/presentation/widgets/custom_app_bar.dart';
import 'package:business_panel/presentation/widgets/info_popup.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flutter_svg/flutter_svg.dart';
import 'package:image_picker/image_picker.dart';
import 'package:persian_datetime_picker/persian_datetime_picker.dart';

class AddDiscountPage extends StatelessWidget {
  final String? discountId;

  const AddDiscountPage({super.key, this.discountId});

  @override
  Widget build(BuildContext context) {
    return BlocProvider(
      create: (context) {
        final bloc = DiscountBloc();
        if (discountId != null) {
          bloc.add(FetchDiscountDetails(discountId!));
        }
        return bloc;
      },
      child: _AddDiscountView(discountId: discountId),
    );
  }
}

class _AddDiscountView extends StatefulWidget {
  final String? discountId;

  const _AddDiscountView({this.discountId});

  @override
  State<_AddDiscountView> createState() => _AddDiscountViewState();
}

class _AddDiscountViewState extends State<_AddDiscountView> {
  final _nameController = TextEditingController();
  final _descController = TextEditingController();
  final _priceController = TextEditingController();
  final _discountPriceController = TextEditingController();

  bool get _isEditMode => widget.discountId != null;

  @override
  void dispose() {
    _nameController.dispose();
    _descController.dispose();
    _priceController.dispose();
    _discountPriceController.dispose();
    super.dispose();
  }

  Future<void> _pickValidityDates(BuildContext context) async {
    Jalali? startDate = await showPersianDatePicker(
      context: context,
      initialDate: Jalali.now(),
      firstDate: Jalali.now(),
      lastDate: Jalali(1500),
    );
    if (startDate == null || !context.mounted) return;

    TimeOfDay? startTime = await showTimePicker(
      context: context,
      initialTime: TimeOfDay.now(),
    );
    if (startTime == null || !context.mounted) return;

    Jalali? endDate = await showPersianDatePicker(
      context: context,
      initialDate: startDate,
      firstDate: startDate,
      lastDate: Jalali(1500),
    );
    if (endDate == null || !context.mounted) return;

    TimeOfDay? endTime = await showTimePicker(
      context: context,
      initialTime: startTime,
    );
    if (endTime == null || !context.mounted) return;

    final DateTime startDateTime = startDate.toDateTime().add(
      Duration(hours: startTime.hour, minutes: startTime.minute),
    );
    final DateTime endDateTime = endDate.toDateTime().add(
      Duration(hours: endTime.hour, minutes: endTime.minute),
    );

    context.read<DiscountBloc>().add(
          ValidityDateChanged(startDate: startDateTime, endDate: endDateTime),
        );
  }

  final List<DiscountTypeEntity> discountTypes = [
    DiscountTypeEntity(id: "dda9aef3-367e-48b3-ba35-8e7744d99659", name: "ساعت خوش"),
    DiscountTypeEntity(id: "57577fac-7d06-4b2e-a577-7d2ce98fee58", name: "رفیق بازی"),
    DiscountTypeEntity(id: "06156635-048b-4ed9-b5d5-2f89824435e1", name: "محصول جانبی رایگان"),
    DiscountTypeEntity(id: "16e7d1e9-29c4-4320-9869-3c986cc20734", name: "کالای مکمل"),
    DiscountTypeEntity(id: "fb600fbb-bab4-4e63-a25b-d8ffdacb7c09", name: "پلکانی"),
    DiscountTypeEntity(id: "488ef29e-415d-4362-b984-509faabac058", name: "دعوت نامه طلایی"),
    DiscountTypeEntity(id: "e03e5823-27d8-4f45-bd6c-f7c11822ec7a", name: "بازگشت وجه"),
    DiscountTypeEntity(id: "bb0eea57-b630-4373-baff-72df72921e67", name: "سایر"),
  ];

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: CustomAppBar(),
      body: BlocConsumer<DiscountBloc, DiscountState>(
        listener: (context, state) {
          if (state.isSuccess) {
            ScaffoldMessenger.of(context).showSnackBar(
              SnackBar(
                  content: Text(
                      "تخفیف با موفقیت ${_isEditMode ? 'ویرایش' : 'ثبت'} شد!"),
                  backgroundColor: Colors.green),
            );
            Navigator.of(context).pop(true);
          }
          if (state.errorMessage != null && !state.isLoadingDetails) {
             ScaffoldMessenger.of(context).showSnackBar(
              SnackBar(
                  content: Text(state.errorMessage!), backgroundColor: Colors.red),
            );
          }
          if (state.productName.isNotEmpty && _nameController.text.isEmpty) {
            _nameController.text = state.productName;
            _descController.text = state.description;
            _priceController.text = state.price;
            _discountPriceController.text = state.discountedPrice;
          }
        },
        builder: (context, state) {
          if (state.isLoadingDetails) {
            return const Center(child: CircularProgressIndicator());
          }
          return SingleChildScrollView(
            padding: const EdgeInsets.all(24),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Text(
                  _isEditMode ? "ویرایش تخفیف" : "تعریف تخفیف جدید",
                  style: const TextStyle(
                      fontWeight: FontWeight.bold, fontSize: 20),
                ),
                const SizedBox(height: 24),
                _buildSectionTitle(
                  title: "بارگذاری عکس از محصول",
                  popupTitle: "یه عکس خوب، یه فروش خوب‌تر!",
                  isMandatory: !_isEditMode,
                  infoText:
                      "عکس واضح، باکیفیت و واقعی از محصولت بذار. ترجیحا از عکس‌های اینترنتی یا تبلیغاتی استفاده نکن.",
                  iconPath: Assets.icons.camera,
                ),
                const SizedBox(height: 16),
                _buildImagePickers(),
                const SizedBox(height: 30),
                _buildTextField(
                  controller: _nameController,
                  label: "نام محصول",
                  isRequired: true,
                  hint: "وافل شکلات فندقی",
                  onChanged: (value) =>
                      context.read<DiscountBloc>().add(ProductNameChanged(value)),
                ),
                const SizedBox(height: 30),
                _buildDiscountTypeDropdown(state), // Pass state here
                const SizedBox(height: 30),
                _buildTextField(
                  controller: _descController,
                  label: "توضیح برای تخفیف",
                  hint: "مثلاً عصرونه، با ۵٪ تخفیف مهمون ما باش! ",
                  isRequired: true,
                  maxLines: 4,
                  maxLength: 200,
                  onChanged: (value) =>
                      context.read<DiscountBloc>().add(DescriptionChanged(value)),
                ),
                const SizedBox(height: 30),
                _buildDateTimePicker(),
                const SizedBox(height: 30),
                _buildTimeRangePicker(context),
                const SizedBox(height: 30),
                _buildTextField(
                  controller: _priceController,
                  label: "قیمت بدون تخفیف",
                  isRequired: true,
                  hint: "مثلاً 240000 تومان",
                  keyboardType: TextInputType.number,
                  onChanged: (value) =>
                      context.read<DiscountBloc>().add(PriceChanged(value)),
                ),
                const SizedBox(height: 30),
                _buildTextField(
                  controller: _discountPriceController,
                  label: "قیمت با تخفیف",
                  hint: "مثلاً 200000 تومان",
                  isRequired: true,
                  keyboardType: TextInputType.number,
                  onChanged: (value) => context
                      .read<DiscountBloc>()
                      .add(DiscountedPriceChanged(value)),
                ),
                const SizedBox(height: 30),
                _buildNotificationRadiusSlider(),
                const SizedBox(height: 30),
                SizedBox(
                  width: double.infinity,
                  child: ElevatedButton(
                    onPressed: state.isSubmitting
                        ? null
                        : () {
                            if (_isEditMode) {
                              context
                                  .read<DiscountBloc>()
                                  .add(UpdateDiscount(widget.discountId!));
                            } else {
                              context.read<DiscountBloc>().add(SubmitDiscount());
                            }
                          },
                    child: state.isSubmitting
                        ? const CircularProgressIndicator(color: Colors.white)
                        : Text(_isEditMode ? "ثبت تغییرات" : "ثبت تخفیف"),
                  ),
                ),
                const SizedBox(height: 30),
              ],
            ),
          );
        },
      ),
    );
  }

  Widget _buildSectionTitle({
    required String title,
    String? popupTitle,
    bool isMandatory = false,
    String? infoText,
    String? iconPath,
  }) {
    return Row(
      mainAxisAlignment: MainAxisAlignment.center,
      children: [
        if (infoText != null && iconPath != null)
          IconButton(
            onPressed: () => showInfoDialog(
              context,
              title: popupTitle ?? title,
              content: infoText,
              iconPath: iconPath,
            ),
            icon: SvgPicture.asset(Assets.icons.infoCircle, width: 17),
          ),
        Text(
          title,
          style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 14),
        ),
        if (isMandatory)
          const Text(' *', style: TextStyle(color: Colors.red, fontSize: 17)),
      ],
    );
  }

  Widget _buildImagePickers() {
    return BlocBuilder<DiscountBloc, DiscountState>(
      buildWhen: (p, c) => p.productImages != c.productImages,
      builder: (context, state) {
        // We ensure the list has at least 2 elements for the UI, filling with null
        final displayImages = List<Map<String, String?>?>.from(state.productImages);
        while (displayImages.length < 2) {
          displayImages.add(null);
        }

        return Row(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          children: List.generate(2, (index) {
            // *** CHANGE IS HERE: Read from the map structure ***
            final imageMap = displayImages[index];
            final imageUrl = imageMap?['url'];
            final isUrl = imageUrl?.startsWith('http') ?? false;

            return GestureDetector(
              onTap: () async {
                final ImagePicker picker = ImagePicker();
                final XFile? image =
                    await picker.pickImage(source: ImageSource.gallery, imageQuality: 80);
                if (image != null && context.mounted) {
                  context
                      .read<DiscountBloc>()
                      .add(ProductImageAdded(image.path, index));
                }
              },
              child: Container(
                width: 125,
                height: 125,
                decoration: BoxDecoration(
                  color: AppColors.uploadElevated,
                  borderRadius: BorderRadius.circular(12),
                  border: Border.all(color: AppColors.uploadElevated),
                  image: imageUrl != null
                      ? DecorationImage(
                          image: isUrl
                              ? NetworkImage(imageUrl)
                              : FileImage(File(imageUrl)) as ImageProvider,
                          fit: BoxFit.cover,
                        )
                      : null,
                ),
                child: imageUrl == null
                    ? Center(
                        child: SvgPicture.asset(
                          Assets.icons.addPic,
                          width: 60,
                        ),
                      )
                    : null,
              ),
            );
          }),
        );
      },
    );
  }

  Widget _buildDiscountTypeDropdown(DiscountState state) {
    // Create a set of available IDs for quick lookup.
    final availableTypeIds = discountTypes.map((type) => type.id).toSet();
    
    // Check if the current discount's type ID is in our list. If not, use null.
    final String? selectedValue = availableTypeIds.contains(state.discountTypeId)
        ? state.discountTypeId
        : null;

    return DropdownButtonFormField<String>(
      value: selectedValue, // Use the safe value here.
      icon: SvgPicture.asset(
        Assets.icons.arrowDown,
        width: 24,
        color: Colors.black,
      ),
      menuMaxHeight: 400,
      hint: const Text("نوع تخفیف را انتخاب کنید"),
      decoration: _inputDecoration("نوع تخفیف", isRequired: true).copyWith(
        contentPadding: const EdgeInsets.symmetric(
          vertical: 14,
          horizontal: 20,
        ),
      ),
      borderRadius: BorderRadius.circular(12.0),
      items: discountTypes.map((type) {
        return DropdownMenuItem(value: type.id, child: Text(type.name));
      }).toList(),
      onChanged: (value) {
        if (value != null) {
          context.read<DiscountBloc>().add(DiscountTypeChanged(value));
        }
      },
    );
  }

  Widget _buildDateTimePicker() {
    return BlocBuilder<DiscountBloc, DiscountState>(
      buildWhen: (previous, current) =>
          previous.startDate != current.startDate ||
          previous.endDate != current.endDate,
      builder: (context, state) {
        String displayText = "انتخاب تاریخ";
        if (state.startDate != null && state.endDate != null) {
          final jalaliStart = DateTimeExtensions(state.startDate!).toJalali();
          final jalaliEnd = DateTimeExtensions(state.endDate!).toJalali();

          final startFormatted =
              '${jalaliStart.year}/${jalaliStart.month.toString().padLeft(2, '0')}/${jalaliStart.day.toString().padLeft(2, '0')} - ${state.startDate!.hour.toString().padLeft(2, '0')}:${state.startDate!.minute.toString().padLeft(2, '0')}';
          final endFormatted =
              '${jalaliEnd.year}/${jalaliEnd.month.toString().padLeft(2, '0')}/${jalaliEnd.day.toString().padLeft(2, '0')} - ${state.endDate!.hour.toString().padLeft(2, '0')}:${state.endDate!.minute.toString().padLeft(2, '0')}';

          displayText = 'از $startFormatted\nتا $endFormatted';
        }
        return InkWell(
          onTap: () => _pickValidityDates(context),
          child: InputDecorator(
            decoration: _inputDecoration(
              "تاریخ اعتبار تخفیف",
              isRequired: true,
            ),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Expanded(
                  child: Text(
                    displayText,
                    textDirection: TextDirection.rtl,
                    style: const TextStyle(fontSize: 15),
                  ),
                ),
                SvgPicture.asset(Assets.icons.calendarSearch),
              ],
            ),
          ),
        );
      },
    );
  }

  Widget _buildTimeRangePicker(BuildContext context) {
    return BlocBuilder<DiscountBloc, DiscountState>(
      buildWhen: (previous, current) =>
          previous.startTime != current.startTime ||
          previous.endTime != current.endTime,
      builder: (context, state) {
        String displayText = "انتخاب بازه زمانی";
        if (state.startTime != null && state.endTime != null) {
          displayText = 'از ساعت ${state.startTime} تا ${state.endTime}';
        }

        return InkWell(
          onTap: () async {
            final TimeOfDay? startTime =
                await showTimePicker(context: context, initialTime: TimeOfDay.now());
            if (startTime == null) return;

            final TimeOfDay? endTime =
                await showTimePicker(context: context, initialTime: startTime);
            if (endTime == null) return;

            final formattedStartTime =
                '${startTime.hour.toString().padLeft(2, '0')}:${startTime.minute.toString().padLeft(2, '0')}';
            final formattedEndTime =
                '${endTime.hour.toString().padLeft(2, '0')}:${endTime.minute.toString().padLeft(2, '0')}';

            context.read<DiscountBloc>().add(
                  TimeRangeChanged(
                      startTime: formattedStartTime, endTime: formattedEndTime),
                );
          },
          child: InputDecorator(
            decoration: _inputDecoration("بازه زمانی معتبر", isRequired: true),
            child: Text(displayText),
          ),
        );
      },
    );
  }

  Widget _buildNotificationRadiusSlider() {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Row(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: [
            Row(
              children: [
                IconButton(
                  onPressed: () => showInfoDialog(
                    context,
                    title: "انتخاب محدوده نمایش تخفیف",
                    content:
                        "محدوده‌ای رو مشخص کن که تخفیف‌هات فقط به کاربرانی که تو اون شعاع هستن نشون داده بشه.",
                    iconPath: Assets.icons.radar2,
                  ),
                  icon: SvgPicture.asset(Assets.icons.infoCircle, width: 17),
                ),
                const Text(
                  "شعاع ارسال اعلان تخفیف به مشتری‌ها",
                  style: TextStyle(fontWeight: FontWeight.bold, fontSize: 14),
                ),
              ],
            ),
          ],
        ),
        BlocBuilder<DiscountBloc, DiscountState>(
          builder: (context, state) {
            return Column(
              children: [
                SliderTheme(
                  data: SliderTheme.of(context).copyWith(
                    activeTrackColor: AppColors.active,
                    inactiveTrackColor: Colors.grey.shade300,
                    trackShape: const RoundedRectSliderTrackShape(),
                    trackHeight: 4.0,
                    thumbColor: AppColors.active,
                    thumbShape:
                        const RoundSliderThumbShape(enabledThumbRadius: 12.0),
                    overlayColor: AppColors.active.withAlpha(32),
                    overlayShape:
                        const RoundSliderOverlayShape(overlayRadius: 28.0),
                  ),
                  child: Slider(
                    value: state.notificationRadius,
                    min: 0,
                    max: 1000,
                    divisions: 100,
                    label: '${state.notificationRadius.toInt()} متر',
                    onChanged: (value) {
                      context
                          .read<DiscountBloc>()
                          .add(NotificationRadiusChanged(value));
                    },
                  ),
                ),
                const SizedBox(height: 7),
                Text(
                  '${state.notificationRadius.toInt()} متر',
                  style: const TextStyle(
                    fontWeight: FontWeight.normal,
                    fontSize: 14,
                    color: Colors.black,
                  ),
                ),
              ],
            );
          },
        ),
      ],
    );
  }

  Widget _buildTextField({
    required String label,
    String? hint,
    bool isRequired = false,
    int? maxLines,
    int? maxLength,
    TextInputType? keyboardType,
    required TextEditingController controller,
    ValueChanged<String>? onChanged,
  }) {
    return ValueListenableBuilder<TextEditingValue>(
      valueListenable: controller,
      builder: (context, value, child) {
        return TextFormField(
          controller: controller,
          onChanged: onChanged,
          maxLines: maxLines,
          maxLength: maxLength,
          keyboardType: keyboardType,
          decoration: _inputDecoration(label, hint: hint, isRequired: isRequired)
              .copyWith(
            counterText: '',
            counter: maxLength != null
                ? Text(
                    '${value.text.length}/$maxLength',
                    style: Theme.of(context).textTheme.bodySmall,
                  )
                : null,
          ),
        );
      },
    );
  }

  InputDecoration _inputDecoration(String label,
      {String? hint, bool isRequired = false}) {
    return InputDecoration(
      hintText: hint,
      hintStyle: const TextStyle(color: Color.fromARGB(255, 95, 95, 95), fontSize: 14),
      label: RichText(
        text: TextSpan(
          text: label,
          style: const TextStyle(
            color: Colors.black,
            fontFamily: 'Dana',
            fontSize: 18,
            fontWeight: FontWeight.bold,
          ),
          children: [
            if (isRequired)
              const TextSpan(
                  text: ' *', style: TextStyle(color: Colors.red)),
          ],
        ),
      ),
    );
  }
}