import 'package:flutter/material.dart';
import 'package:mc_common_app/classes/app_state.dart';
import 'package:mc_common_app/extensions/int_extensions.dart';
import 'package:mc_common_app/extensions/string_extensions.dart';
import 'package:mc_common_app/generated/locale_keys.g.dart';
import 'package:mc_common_app/models/general_models/generic_resp_model.dart';
import 'package:mc_common_app/models/subscriptions_models/branch_user_selection_model.dart';
import 'package:mc_common_app/models/subscriptions_models/subscription_model.dart';
import 'package:mc_common_app/theme/colors.dart';
import 'package:mc_common_app/utils/enums.dart';
import 'package:mc_common_app/utils/navigator.dart';
import 'package:mc_common_app/utils/utils.dart';
import 'package:mc_common_app/view_models/payment_view_model.dart';
import 'package:mc_common_app/view_models/subscriptions_view_model.dart';
import 'package:mc_common_app/views/payments/payment_methods_view.dart';
import 'package:mc_common_app/widgets/button/show_fill_button.dart';
import 'package:mc_common_app/widgets/extensions/extensions_widget.dart';
import 'package:provider/provider.dart';
import 'package:easy_localization/easy_localization.dart';

class DowngradeDataSheet extends StatefulWidget {
  final Subscription subscription;

  const DowngradeDataSheet(this.subscription, {super.key});

  @override
  State<DowngradeDataSheet> createState() => _DowngradeDataSheetState();
}

class _DowngradeDataSheetState extends State<DowngradeDataSheet> {
  @override
  void initState() {
    super.initState();
    context.read<SubscriptionsVM>().getSPBranchUserGet();
  }

  // The provider's current active plan (not the plan being downgraded to) holds how many
  // branches/sub-users they currently have -- confirmed with the user this is where
  // "current totals" come from, as opposed to widget.subscription which is the target plan.
  Subscription? get _currentSubscription {
    final list = AppState().getproviderSubscription;
    return list.isEmpty ? null : list.first;
  }

  // subscriptionBranches/subscriptionSubUsers are each plan's own allowed quota.
  // totalBranches/totalSubUsers looked plausible but turned out to be unrelated (they
  // read identically on both the current and target plan records in testing).
  int get _currentBranches => _currentSubscription?.subscriptionBranches ?? 0;

  int get _currentUsers => _currentSubscription?.subscriptionSubUsers ?? 0;

  int get _targetBranches => widget.subscription.subscriptionBranches ?? 0;

  int get _targetUsers => widget.subscription.subscriptionSubUsers ?? 0;

  int get _branchesToRemove => (_currentBranches - _targetBranches).clamp(0, _currentBranches);

  int get _usersToRemove => (_currentUsers - _targetUsers).clamp(0, _currentUsers);

  // Selecting a whole branch removes every user in it too, so that counts towards the
  // user quota as well, not just the branch quota.
  _SelectedCounts _selectedCounts(List<BranchSelectionModel> branchSelectionList) {
    int selectedBranches = 0;
    int selectedUsers = 0;
    for (var branch in branchSelectionList) {
      if (branch.isSelected) {
        selectedBranches++;
        selectedUsers += branch.usersList.length;
      } else {
        selectedUsers += branch.usersList.where((u) => u.isSelected).length;
      }
    }
    return _SelectedCounts(selectedBranches, selectedUsers);
  }

  Widget _buildRequirementCounter(List<BranchSelectionModel> branchSelectionList) {
    final counts = _selectedCounts(branchSelectionList);
    final remainingBranches = (_branchesToRemove - counts.branches).clamp(0, _branchesToRemove);
    final remainingUsers = (_usersToRemove - counts.users).clamp(0, _usersToRemove);

    if (remainingBranches == 0 && remainingUsers == 0) {
      return "You have selected enough branches/users to downgrade.".toText(fontSize: 13, color: MyColors.primaryColor, isBold: true);
    }

    final parts = <String>[
      if (remainingBranches > 0) "$remainingBranches more branch${remainingBranches == 1 ? '' : 'es'}",
      if (remainingUsers > 0) "$remainingUsers more user${remainingUsers == 1 ? '' : 's'}",
    ];
    return "Select ${parts.join(' and ')} to downgrade.".toText(fontSize: 13, color: MyColors.textColor, isBold: true);
  }

  @override
  Widget build(BuildContext context) {
    final targetBranchesText = "$_targetBranches branch${_targetBranches == 1 ? '' : 'es'}";
    final targetUsersText = "$_targetUsers sub-user${_targetUsers == 1 ? '' : 's'}";
    return SizedBox(
      width: double.infinity,
      height: MediaQuery.of(context).size.height / 1.2,
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Padding(
            padding: const EdgeInsets.all(12),
            child: Column(
              children: [
                "Deactivate the branches & users".toText(
                  fontSize: 19,
                  isBold: true,
                ),
                8.height,
                LocaleKeys.downgradeDeactivateInstruction.tr(namedArgs: {'branches': targetBranchesText, 'users': targetUsersText}).toText(
                  fontSize: 14,
                  color: MyColors.textColor,
                ),
                12.height,
                // isStartNow is passed as false for a downgrade, so the new package isn't
                // applied immediately -- it takes effect once the current one expires. Make
                // that explicit so it isn't mistaken for an immediate switch.
                Row(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    const Icon(Icons.info_outline_rounded, size: 18, color: MyColors.textColor),
                    8.width,
                    Expanded(
                      child: LocaleKeys.downgradeAppliedAfterExpiry.tr().toText(fontSize: 13, color: MyColors.textColor),
                    ),
                  ],
                ).toContainer(
                  backgroundColor: MyColors.greyButtonColor,
                  paddingAll: 10,
                  borderRadius: 6,
                ),
              ],
            ),
          ),
          Expanded(
            child: Consumer<SubscriptionsVM>(
              builder: (BuildContext context, model, Widget? child) {
                final counts = model.branchSelectionList == null ? _SelectedCounts(0, 0) : _selectedCounts(model.branchSelectionList!);
                final canProceed = model.branchSelectionList != null && counts.branches >= _branchesToRemove && counts.users >= _usersToRemove;
                return Column(
                  children: [
                    if (model.branchSelectionList != null)
                      Padding(
                        padding: const EdgeInsets.symmetric(horizontal: 12),
                        child: _buildRequirementCounter(model.branchSelectionList!),
                      ),
                    if (model.branchSelectionList != null) 8.height,
                    Expanded(
                      child: model.branchSelectionList == null
                          ? const Center(child: CircularProgressIndicator())
                          : ListView.separated(
                              itemBuilder: (context, index) {
                                return showBranchItem(model, model.branchSelectionList![index]);
                              },
                              separatorBuilder: (context, index) {
                                return 12.height;
                              },
                              padding: const EdgeInsets.all(12),
                              itemCount: model.branchSelectionList?.length ?? 0,
                            ),
                    ),
                    ShowFillButton(
                      title: LocaleKeys.next.tr(),
                      maxWidth: double.infinity,
                      margin: const EdgeInsets.all(12),
                      isDisabled: !canProceed,
                      onPressed: () async {
                        List<int> listOfBranches = [];
                        List<int> listOfUsers = [];
                        for (var branch in model.branchSelectionList!) {
                          if (branch.isSelected) {
                            listOfBranches.add(branch.branchId);
                            for (var user in branch.usersList) {
                              listOfUsers.add(user.userId);
                            }
                          } else {
                            for (var user in branch.usersList) {
                              if (user.isSelected) {
                                listOfUsers.add(user.userId);
                              }
                            }
                          }
                        }
                        if (listOfBranches.isNotEmpty || listOfUsers.isNotEmpty) {
                          navigateTo(
                            context,
                            PaymentMethodsView(
                              paymentType: PaymentTypes.subscription,
                              onTempContinue: () async {
                                Utils.showLoading(context);
                                GenericRespModel response = await model.payForSubscription(
                                  subscriptionId: widget.subscription.id!,
                                  isStartNow: false,
                                  isRenew: false,
                                  amount: widget.subscription.price.toString(),
                                  isDegrade: true,
                                  listOfBranches: listOfBranches,
                                  listOfUsers: listOfUsers,
                                );

                                Utils.hideLoading(context);

                                if (response.messageStatus == 1) {
                                  if (response.message!.contains("Your current sub-users are not")) {
                                    Utils.showToast(response.message.toString());
                                    context.read<SubscriptionsVM>().getMySubscriptions(AppState().getUser.data?.userInfo?.providerId.toString() ?? "");
                                    pop(context);
                                    return false;
                                  } else {
                                    context.read<PaymentVM>().updateOrderProviderSubscriptionId(id: response.data);

                                    // Utils.showToast(
                                    //     "Subscriptions is successfully updated");
                                    return true;
                                  }
                                } else {
                                  Utils.showToast(response.message.toString());
                                  context.read<SubscriptionsVM>().getMySubscriptions(AppState().getUser.data?.userInfo?.providerId.toString() ?? "");
                                  return false;
                                }
                              },
                            ),
                          );
                        }
                      },
                    ),
                  ],
                );
              },
            ),
          ),
        ],
      ),
    );
  }

  Widget showBranchItem(SubscriptionsVM viewModel, BranchSelectionModel model) {
    return Row(
      crossAxisAlignment: CrossAxisAlignment.start,
      mainAxisSize: MainAxisSize.min,
      children: [
        // Padding around the checkbox widens its tap target (18x18 alone is too small to
        // hit reliably) without growing the checkbox's own visual size or changing the
        // row's separate tap-to-expand behavior.
        Padding(
          padding: const EdgeInsets.all(10),
          child: customCheckBox(model.isSelected),
        ).onPress(() {
          model.isSelected = !model.isSelected;
          if (model.isSelected) {
            for (var user in model.usersList) {
              user.isSelected = true;
            }
          } else {
            for (var user in model.usersList) {
              user.isSelected = false;
            }
          }
          model.isOpend = true;
          viewModel.setState(ViewState.idle);
        }),
        12.width,
        Expanded(
          child: Column(
            mainAxisSize: MainAxisSize.min,
            children: [
              SizedBox(
                width: double.infinity,
                child: Row(
                  children: [
                    Expanded(
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.start,
                        children: [
                          model.branchName.toText(
                            fontSize: 18,
                            isBold: true,
                          ),
                          ("${model.usersList.length} Users").toText(
                            fontSize: 10,
                            color: MyColors.lightTextColor,
                          )
                        ],
                      ),
                    ),
                    Row(
                      mainAxisAlignment: MainAxisAlignment.center,
                      crossAxisAlignment: CrossAxisAlignment.center,
                      children: [
                        Icon(
                          model.isOpend ? Icons.keyboard_arrow_up_rounded : Icons.keyboard_arrow_down_rounded,
                        ),
                      ],
                    ),
                  ],
                ),
              ),
              if (model.isOpend) 12.height,
              if (model.isOpend)
                ListView.separated(
                  itemBuilder: (context, index) {
                    return Row(
                      children: [
                        customCheckBox(model.usersList[index].isSelected),
                        8.width,
                        model.usersList[index].userName.toText(
                          fontSize: 14,
                        ),
                      ],
                    ).onPress(() {
                      // for (int i = 0; i < model.usersList.length; i++) {
                      //   if (i != index) {
                      //     model.usersList[index].isSelected = false;
                      //   }
                      // }
                      model.usersList[index].isSelected = !model.usersList[index].isSelected;
                      viewModel.setState(ViewState.idle);
                    });
                  },
                  separatorBuilder: (context, index) {
                    return 12.height;
                  },
                  physics: const NeverScrollableScrollPhysics(),
                  shrinkWrap: true,
                  itemCount: model.usersList.length,
                ),
            ],
          ).onPress(() {
            model.isOpend = !model.isOpend;
            viewModel.setState(ViewState.idle);
          }),
        )
      ],
    ).toWhiteContainer(
      width: double.infinity,
      pading: const EdgeInsets.all(12),
    );
  }

  Widget customCheckBox(bool isChecked) {
    return SizedBox(
      height: 18,
      width: 18,
      child: isChecked
          ? const Icon(
              Icons.done,
              color: Colors.white,
              size: 14,
            )
          : const SizedBox(),
    ).toContainer(
      isEnabledBorder: true,
      paddingAll: 0,
      borderRadius: 0,
      borderWidget: 1,
      borderColor: MyColors.primaryColor,
      backgroundColor: isChecked ? MyColors.primaryColor : Colors.transparent,
    );
  }
}

class _SelectedCounts {
  final int branches;
  final int users;

  _SelectedCounts(this.branches, this.users);
}