import 'package:cheminova/models/pd_rd_response_model.dart';
import 'package:cheminova/models/product_model.dart';
import 'package:cheminova/provider/product_provider.dart';
import 'package:cheminova/screens/data_submit_successfull.dart';
import 'package:cheminova/utils/string_extension.dart';
import 'package:cheminova/widgets/common_app_bar.dart';
import 'package:cheminova/widgets/common_background.dart';
import 'package:cheminova/widgets/common_drawer.dart';
import 'package:cheminova/widgets/common_elevated_button.dart';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';




class AddProductsScreen extends StatefulWidget {
  final PdRdResponseModel distributor;
  final String distributorType;
  const AddProductsScreen({
    super.key,
    required this.distributor,
    required this.distributorType,
  });

  @override
  State<AddProductsScreen> createState() => _AddProductsScreenState();
}

class _AddProductsScreenState extends State<AddProductsScreen> {
  List<Product> filteredProducts = [];
  final searchController = TextEditingController();
   final ScrollController scrollController = ScrollController();
   late ProductProvider provider;
 int currentpage = 1;
  bool hasMoreData = true; // To track if more data is available
  bool isLoading = false; // To track loading state
  @override
  void initState() {
    super.initState();
    provider = Provider.of<ProductProvider>(context, listen: false);
  loadProducts();

    scrollController.addListener(() {
      if (scrollController.position.pixels ==
          scrollController.position.maxScrollExtent) {
         loadProducts();
      }
    });

  }







 //  Future<void> loadProducts() async {
 //   // provider = Provider.of<ProductProvider>(context, listen: false);
 // await  provider.getProducts(currentpage);
 //    setState(() {
 //      //provider.selectedProducts.clear();
 //     // isLoading = true;
 //      currentpage++;
 //     filteredProducts = provider.productList;
 //    });
 //  }


  // Future<void> loadProducts() async {
  //   if (isLoading || !hasMoreData) return; // Prevent multiple simultaneous calls
  //
  //   setState(() {
  //     isLoading = true; // Show loading state
  //   });
  //
  //   // Fetch products from the provider
  //   await provider.getProducts(currentpage);
  //
  //   setState(() {
  //     final newProducts = provider.productList;
  //
  //     // Add only unique products to the list
  //     for (var product in newProducts) {
  //       if (!filteredProducts.any((p) => p.id == product.id)) {
  //         filteredProducts.add(product);
  //
  //       }
  //     }
  //
  //     // Check if more data is available
  //     hasMoreData = newProducts.isNotEmpty;
  //
  //     isLoading = false; // Remove loading state
  //     currentpage++;
  //   });
  // }


  Future<void> loadProducts() async {
    if (isLoading || !hasMoreData) return; // Prevent duplicate API calls
    setState(() {
      isLoading = true;
    });

    // Fetch products
    await provider.getProducts(currentpage);

    setState(() {
      final newProducts = provider.productList;

      // Add only unique products to filteredProducts
      for (var product in newProducts) {
        if (!filteredProducts.any((p) => p.id == product.id)) {
          filteredProducts.add(product);
        }
      }

      currentpage++;
      isLoading = false;

      // If no new products are returned, stop further API calls
      if (newProducts.isEmpty) {
        hasMoreData = false;
      }
    });
  }

  void filterProducts(String query) {
    setState(() {
      final provider = Provider.of<ProductProvider>(context, listen: false);
      filteredProducts = provider.productList.where((product) {
        final productNameLower = product.name.toLowerCase();
        final productSkuLower = product.SKU.toLowerCase();
        final searchLower = query.toLowerCase();

        return productNameLower.contains(searchLower) ||
            productSkuLower.contains(searchLower);
      }).toList();
    });
  }

  @override
  Widget build(BuildContext context) {
    return CommonBackground(
      child: Scaffold(
        backgroundColor: Colors.transparent,
        appBar: CommonAppBar(
          actions: [
            IconButton(
              onPressed: () {
                Navigator.pop(context);
              },
              icon: Image.asset('assets/Back_attendance.png'),
              padding: const EdgeInsets.only(right: 20),
            ),
          ],
          title: Text(
            widget.distributor.name!.capitalize(),
            style: const TextStyle(
              fontSize: 20,
              color: Colors.black,
              fontWeight: FontWeight.w400,
              fontFamily: 'Anek',
            ),
          ),
          backgroundColor: Colors.transparent,
          elevation: 0,
        ),
        drawer: const CommonDrawer(),
        body: Consumer<ProductProvider>(
          builder: (context, provider, child) {
            if (provider.isLoading) {
              return const Center(child: CircularProgressIndicator());
            }

            return Stack(
              children: [
                Column(
                  children: [
                    if (provider.selectedProducts.isNotEmpty)
                      Expanded(
                        child: ListView.builder(
                          itemCount: provider.selectedProducts.length,
                          itemBuilder: (context, index) {
                            return ProductBlock(index: index);
                          },
                        ),
                      ),
                  ],
                ),
                Align(
                  alignment: provider.selectedProducts.isEmpty
                      ? Alignment.center
                      : Alignment.bottomCenter,
                  child: Padding(
                    padding: const EdgeInsets.all(16.0),
                    child: Column(
                      mainAxisSize: MainAxisSize.min,
                      children: [
                        FloatingActionButton.extended(
                          onPressed: () {
                            showModalBottomSheet(
                              isScrollControlled: true,
                              constraints: BoxConstraints(
                                maxHeight:
                                MediaQuery.of(context).size.height * 0.9,
                              ),
                              context: context,
                              builder: (BuildContext context) {
                                return Consumer<ProductProvider>(
                                  builder: (context, value, child) =>
                                      StatefulBuilder(
                                        builder: (context, setState) {
                                          return Column(
                                            children: [
                                              Padding(
                                                padding: const EdgeInsets.all(18.0),
                                                child: TextField(
                                                  controller: searchController,
                                                  decoration: const InputDecoration(
                                                    labelText:
                                                    'Search by name or SKU',
                                                    border: OutlineInputBorder(),
                                                    prefixIcon: Icon(Icons.search),
                                                  ),
                                                  onChanged: (value) {
                                                    filterProducts(value);
                                                    setState(() {});
                                                  },
                                                ),
                                              ),
                                              Expanded(
                                                child: ListView.builder(
                                                  controller: scrollController,
                                                  itemCount:
                                                  filteredProducts.length +(isLoading ? 1 : 0),
                                                  itemBuilder: (context, index) {
                                                    if (index == filteredProducts.length) {
                                                      // Show a loading indicator while fetching more products
                                                      return const Center(
                                                        child: Padding(
                                                          padding: EdgeInsets.all(16.0),
                                                          child: CircularProgressIndicator(),
                                                        ),
                                                      );
                                                    }
                                                    bool isAlreadySelected =
                                                    provider.selectedProducts
                                                        .contains(
                                                        filteredProducts[
                                                        index]);
                                                    return Card(
                                                      child: ListTile(
                                                        title: Text(
                                                          filteredProducts[index]
                                                              .name
                                                              .capitalize(),
                                                          style: TextStyle(
                                                            color: isAlreadySelected
                                                                ? Colors.grey
                                                                : Colors.black,
                                                          ),
                                                        ),
                                                        subtitle: Text(
                                                          filteredProducts[index]
                                                              .SKU,
                                                          style: TextStyle(
                                                            color: isAlreadySelected
                                                                ? Colors.grey
                                                                : Colors.black,
                                                          ),
                                                        ),
                                                        onTap: isAlreadySelected
                                                            ? null
                                                            : () {
                                                          setState(() {
                                                            provider
                                                                .selectedProducts
                                                                .add(filteredProducts[
                                                            index]);
                                                          });
                                                          Navigator.pop(
                                                              context);
                                                        },
                                                      ),
                                                    );
                                                  },
                                                ),
                                              ),
                                            ],
                                          );
                                        },
                                      ),
                                );
                              },
                            ).whenComplete(() {
                              setState(() {});
                            });
                          },
                          backgroundColor: Colors.white,
                          icon: const Icon(Icons.add, color: Colors.black),
                          label: const Text(
                            'Add Products',
                            style: TextStyle(color: Colors.black),
                          ),
                        ),
                        if (provider.selectedProducts.isNotEmpty) ...[
                          const SizedBox(height: 16.0),
                          CommonElevatedButton(
                            borderRadius: 30,
                            width: double.infinity,
                            height: kToolbarHeight - 10,
                            text: 'SUBMIT',
                            backgroundColor: const Color(0xff004791),
                            onPressed: () {
                              provider
                                  .submitSelectedProducts(
                                  (widget.distributorType ==
                                      'Principal Distributor')
                                      ? 'PrincipalDistributor'
                                      : 'RetailDistributor',
                                  widget.distributor.id!)
                                  .then((value) {
                                if (value) {
                                  Navigator.push(
                                    context,
                                    MaterialPageRoute(
                                      builder: (context) =>
                                      const DataSubmitSuccessfull(),
                                    ),
                                  );
                                } else {
                                  ScaffoldMessenger.of(context).showSnackBar(
                                    const SnackBar(
                                      content: Text("Insufficient stock"),
                                    ),
                                  );
                                }
                              });
                            },
                          ),
                        ],
                      ],
                    ),
                  ),
                ),
              ],
            );
          },
        ),
      ),
    );
  }
}


// class AddProductsScreen extends StatefulWidget {
//   final PdRdResponseModel distributor;
//   final String distributorType;
//   const AddProductsScreen({
//     super.key,
//     required this.distributor,
//     required this.distributorType,
//   });
//
//   @override
//   State<AddProductsScreen> createState() => _AddProductsScreenState();
// }


// class _AddProductsScreenState extends State<AddProductsScreen> {
//   List<Product> filteredProducts = [];
//   final searchController = TextEditingController();
//   late ProductProvider provider;
//   int currentPage = 1;
//   bool isLoadingMore = false;
//   bool hasMoreProducts = true;
//   final ScrollController scrollController = ScrollController();
//
//   @override
//   void initState() {
//     super.initState();
//     provider = Provider.of<ProductProvider>(context, listen: false);
//    // loadProducts();
//
//     provider.getProducts(currentPage);
//     scrollController.addListener(() {
//       if (scrollController.position.pixels == scrollController.position.maxScrollExtent) {
//         // Load the next page when reaching the bottom
//         currentPage++;
//         provider.getProducts(currentPage);
//       }
//     });
//   }
//
//   Future<void> loadProducts() async {
//     await provider.getProducts(currentPage);
//
//     setState(() {
//       filteredProducts = provider.productList;
//     });
//   }
//
//   Future<void> loadMoreProducts() async {
//     setState(() {
//       isLoadingMore = true;
//     });
//
//     currentPage++;
//     await provider.getProducts(currentPage);
//
//     setState(() {
//       // Check if more products were fetched
//       if (provider.productList.isEmpty) {
//         hasMoreProducts = false; // No more products to load
//       } else {
//         filteredProducts.addAll(provider.productList);
//       }
//       isLoadingMore = false;
//     });
//   }
//
//   void filterProducts(String query) {
//     setState(() {
//       filteredProducts = provider.productList.where((product) {
//         final productNameLower = product.name.toLowerCase();
//         final productSkuLower = product.SKU.toLowerCase();
//         final searchLower = query.toLowerCase();
//
//         return productNameLower.contains(searchLower) ||
//             productSkuLower.contains(searchLower);
//       }).toList();
//     });
//   }
//
//   @override
//   Widget build(BuildContext context) {
//     return CommonBackground(
//       child: Scaffold(
//         backgroundColor: Colors.transparent,
//         appBar: CommonAppBar(
//           actions: [
//             IconButton(
//               onPressed: () {
//                 Navigator.pop(context);
//               },
//               icon: Image.asset('assets/Back_attendance.png'),
//               padding: const EdgeInsets.only(right: 20),
//             ),
//           ],
//           title: Text(
//             widget.distributor.name!.capitalize(),
//             style: const TextStyle(
//               fontSize: 20,
//               color: Colors.black,
//               fontWeight: FontWeight.w400,
//               fontFamily: 'Anek',
//             ),
//           ),
//           backgroundColor: Colors.transparent,
//           elevation: 0,
//         ),
//         drawer: const CommonDrawer(),
//         body: Consumer<ProductProvider>(
//           builder: (context, provider, child) {
//             if (provider.isLoading && provider.productList.isEmpty) {
//               return const Center(child: CircularProgressIndicator());
//             }
//
//             return Stack(
//               children: [
//                 Column(
//                   children: [
//                     if (provider.selectedProducts.isNotEmpty)
//                       Expanded(
//                         child: ListView.builder(
//                           //controller: scrollController,
//                           itemCount:  filteredProducts.length , // Add 1 for the loading indicator
//                           itemBuilder: (context, index) {
//                             final product = provider.productList[index];
//                             if (index < filteredProducts.length) {
//                               return ProductBlock(index: index);
//                             } else if (isLoadingMore) {
//                               return const Center(
//                                 child: Padding(
//                                   padding: EdgeInsets.all(16.0),
//                                   child: CircularProgressIndicator(),
//                                 ),
//                               );
//                             } else {
//                               return const SizedBox(); // Empty widget when no more products to load
//                             }
//                           },
//                         ),
//                       ),
//                   ],
//                 ),
//                 Align(
//                   alignment: provider.selectedProducts.isEmpty
//                       ? Alignment.center
//                       : Alignment.bottomCenter,
//                   child: Padding(
//                     padding: const EdgeInsets.all(16.0),
//                     child: Column(
//                       mainAxisSize: MainAxisSize.min,
//                       children: [
//                         FloatingActionButton.extended(
//                           onPressed: () {
//                             showModalBottomSheet(
//                               isScrollControlled: true,
//                               constraints: BoxConstraints(
//                                 maxHeight:
//                                 MediaQuery.of(context).size.height * 0.9,
//                               ),
//                               context: context,
//                               builder: (BuildContext context) {
//                                 return Consumer<ProductProvider>(
//                                   builder: (context, value, child) =>
//                                       StatefulBuilder(
//                                         builder: (context, setState) {
//                                           return Column(
//                                             children: [
//                                               Padding(
//                                                 padding: const EdgeInsets.all(18.0),
//                                                 child: TextField(
//                                                   controller: searchController,
//                                                   decoration: const InputDecoration(
//                                                     labelText:
//                                                     'Search by name or SKU',
//                                                     border: OutlineInputBorder(),
//                                                     prefixIcon: Icon(Icons.search),
//                                                   ),
//                                                   onChanged: (value) {
//                                                     filterProducts(value);
//                                                     setState(() {});
//                                                   },
//                                                 ),
//                                               ),
//                                               Expanded(
//                                                 child: ListView.builder(
//                                                   controller: scrollController,
//                                                   itemCount: provider.productList.length,
//                                                   itemBuilder: (context, index) {
//                                                     final product = provider.productList[index];
//                                                     bool isAlreadySelected = provider
//                                                         .selectedProducts
//                                                         .contains(
//                                                         product);
//                                                     return Card(
//                                                       child: ListTile(
//                                                         title: Text(
//                                                           product
//                                                               .name
//                                                               .capitalize(),
//                                                           style: TextStyle(
//                                                             color: isAlreadySelected
//                                                                 ? Colors.grey
//                                                                 : Colors.black,
//                                                           ),
//                                                         ),
//                                                         subtitle: Text(
//                                                           product.SKU,
//                                                           style: TextStyle(
//                                                             color: isAlreadySelected
//                                                                 ? Colors.grey
//                                                                 : Colors.black,
//                                                           ),
//                                                         ),
//                                                         onTap: isAlreadySelected
//                                                             ? null
//                                                             : () {
//                                                           setState(() {
//                                                             provider
//                                                                 .selectedProducts
//                                                                 .add(
//                                                                 product);
//                                                           });
//                                                           Navigator.pop(
//                                                               context);
//                                                         },
//                                                       ),
//                                                     );
//                                                   },
//                                                 ),
//                                               ),
//                                             ],
//                                           );
//                                         },
//                                       ),
//                                 );
//                               },
//                             ).whenComplete(() {
//                               setState(() {});
//                             });
//                           },
//                           backgroundColor: Colors.white,
//                           icon: const Icon(Icons.add, color: Colors.black),
//                           label: const Text(
//                             'Add Products',
//                             style: TextStyle(color: Colors.black),
//                           ),
//                         ),
//                         if (provider.selectedProducts.isNotEmpty) ...[
//                           const SizedBox(height: 16.0),
//                           CommonElevatedButton(
//                             borderRadius: 30,
//                             width: double.infinity,
//                             height: kToolbarHeight - 10,
//                             text: 'SUBMIT',
//                             backgroundColor: const Color(0xff004791),
//                             onPressed: () {
//                               provider
//                                   .submitSelectedProducts(
//                                   (widget.distributorType ==
//                                       'Principal Distributor')
//                                       ? 'PrincipalDistributor'
//                                       : 'RetailDistributor',
//                                   widget.distributor.id!)
//                                   .then((value) {
//                                 if (value) {
//                                   Navigator.push(
//                                     context,
//                                     MaterialPageRoute(
//                                       builder: (context) =>
//                                       const DataSubmitSuccessfull(),
//                                     ),
//                                   );
//                                 } else {
//                                   ScaffoldMessenger.of(context).showSnackBar(
//                                     const SnackBar(
//                                       content: Text("Insufficient stock"),
//                                     ),
//                                   );
//                                 }
//                               });
//                             },
//                           ),
//                         ],
//                       ],
//                     ),
//                   ),
//                 ),
//               ],
//             );
//           },
//         ),
//       ),
//     );
//   }
// }





class ProductBlock extends StatefulWidget {
  final int index;

  const ProductBlock({super.key, required this.index});

  @override
  State<ProductBlock> createState() => _ProductBlockState();
}

class _ProductBlockState extends State<ProductBlock> {
  final saleController = TextEditingController();
  final inventoryController = TextEditingController();
  String? errorMessage;
  late ProductProvider provider;

  @override
  void initState() {
    super.initState();
    provider = Provider.of<ProductProvider>(context, listen: false);
  }

  bool validateInput() {
    setState(() {
      if (saleController.text.isNotEmpty &&
          inventoryController.text.isNotEmpty) {
        // Check if both inputs are valid integers
        try {
          int.parse(saleController.text);
          int.parse(inventoryController.text);
        } catch (e) {
          // Handle the case where input is not a valid integer
          errorMessage = 'Please enter valid integer values for both fields';
        }
      } else {
        errorMessage = null;
      }
    });
    return errorMessage == null;
  }

  @override
  Widget build(BuildContext context) {
    return Card(
      // color: !widget.product.isPurchased ? Colors.white54 : Colors.white,
      color: Colors.white,
      margin: const EdgeInsets.all(8),
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text(
                'Product: ${provider.selectedProducts[widget.index].name.capitalize()}',
                style: const TextStyle(fontSize: 16)),
            Text('SKU: ${provider.selectedProducts[widget.index].SKU}',
                style: const TextStyle(fontSize: 15)),
            const SizedBox(height: 8),
            TextField(
              controller: saleController,
              decoration: const InputDecoration(labelText: 'Sale'),
              keyboardType: TextInputType.number,
              // enabled: widget.product.isPurchased,
              enabled: true,
              onChanged: (_) => validateInput()
                  ? provider.selectedProducts[widget.index].sale =
                  int.parse(saleController.text)
                  : null,
            ),
            TextField(
              controller: inventoryController,
              decoration: const InputDecoration(labelText: 'Inventory'),
              keyboardType: TextInputType.number,
              // enabled: widget.product.isPurchased,
              enabled: true,
              onChanged: (_) => validateInput()
                  ? provider.selectedProducts[widget.index].inventory =
                  int.parse(inventoryController.text)
                  : null,
            ),
            if (errorMessage != null)
              Padding(
                padding: const EdgeInsets.only(top: 8.0),
                child: Text(
                  errorMessage!,
                  style: const TextStyle(color: Colors.red),
                ),
              ),
          ],
        ),
      ),
    );
  }
}
// class ProductBlock extends StatefulWidget {
//   final int index;
//
//   const ProductBlock({super.key, required this.index});
//
//   @override
//   State<ProductBlock> createState() => _ProductBlockState();
// }
//
// class _ProductBlockState extends State<ProductBlock> {
//   final saleController = TextEditingController();
//   final inventoryController = TextEditingController();
//   String? errorMessage;
//   late ProductProvider provider;
//
//   @override
//   void initState() {
//     super.initState();
//     provider = Provider.of<ProductProvider>(context, listen: false);
//   }
//
//   bool validateInput() {
//     setState(() {
//       if (saleController.text.isNotEmpty &&
//           inventoryController.text.isNotEmpty) {
//         // Check if both inputs are valid integers
//         try {
//           int.parse(saleController.text);
//           int.parse(inventoryController.text);
//         } catch (e) {
//           // Handle the case where input is not a valid integer
//           errorMessage = 'Please enter valid integer values for both fields';
//         }
//       } else {
//         errorMessage = null;
//       }
//     });
//     return errorMessage == null;
//   }
//
//   @override
//   Widget build(BuildContext context) {
//     return Card(
//       // color: !widget.product.isPurchased ? Colors.white54 : Colors.white,
//       color: Colors.white,
//       margin: const EdgeInsets.all(8),
//       child: Padding(
//         padding: const EdgeInsets.all(16),
//         child: Column(
//           crossAxisAlignment: CrossAxisAlignment.start,
//           children: [
//             Text(
//                 'Product: ${provider.productList[widget.index].name.capitalize()}',
//                 style: const TextStyle(fontSize: 16)),
//             Text('SKU: ${provider.productList[widget.index].SKU}',
//                 style: const TextStyle(fontSize: 15)),
//             const SizedBox(height: 8),
//             TextField(
//               controller: saleController,
//               decoration: const InputDecoration(labelText: 'Sale'),
//               keyboardType: TextInputType.number,
//               // enabled: widget.product.isPurchased,
//               enabled: true,
//               onChanged: (_) => validateInput()
//                   ? provider.productList[widget.index].sale =
//                   int.parse(saleController.text)
//                   : null,
//             ),
//             TextField(
//               controller: inventoryController,
//               decoration: const InputDecoration(labelText: 'Inventory'),
//               keyboardType: TextInputType.number,
//               // enabled: widget.product.isPurchased,
//               enabled: true,
//               onChanged: (_) => validateInput()
//                   ? provider.productList[widget.index].inventory =
//                   int.parse(inventoryController.text)
//                   : null,
//             ),
//             if (errorMessage != null)
//               Padding(
//                 padding: const EdgeInsets.only(top: 8.0),
//                 child: Text(
//                   errorMessage!,
//                   style: const TextStyle(color: Colors.red),
//                 ),
//               ),
//           ],
//         ),
//       ),
//     );
//   }
// }