import 'package:cdb_ui/api.dart';
import 'package:cdb_ui/pages/consume.dart';
import 'package:cdb_ui/pages/supply.dart';
import 'package:flutter/material.dart';
import 'package:intl/intl.dart';
import 'package:qr_bar_code/qr/qr.dart';

class TransactionPage extends StatefulWidget {
  final Transaction transaction;
  final Function? refresh;

  const TransactionPage(this.transaction, {this.refresh, super.key});

  @override
  State<TransactionPage> createState() => _TransactionPageState();
}

class _TransactionPageState extends State<TransactionPage> {
  late Transaction transaction;

  @override
  void initState() {
    super.initState();
    transaction = widget.transaction;
  }

  Future<void> reload() async {
    if (widget.refresh != null) {
      widget.refresh!();
    }

    var updateTransaction = await API().getTransaction(transaction.uuid);

    setState(() {
      transaction = updateTransaction;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(API().getItem(transaction.item).name),
        actions: [
          IconButton(
              onPressed: () {
                var locations = API().getLocations();
                List<String> locationList = locations.keys.toList();
                String? selectedLocationID;

                showDialog(
                  context: context,
                  builder: (BuildContext context) {
                    return AlertDialog(
                      title: const Text('Move Transaction'),
                      content: Row(
                        mainAxisSize: MainAxisSize.min,
                        children: [
                          DropdownButton<String>(
                            value: selectedLocationID,
                            onChanged: (value) {
                              selectedLocationID = value!;
                              API()
                                  .moveTransaction(widget.transaction.uuid,
                                      selectedLocationID!)
                                  .then((x) {
                                Navigator.of(context).pop();
                              });

                              setState(() {});
                            },
                            items: locationList
                                .map<DropdownMenuItem<String>>((locationID) {
                              return DropdownMenuItem<String>(
                                value: locationID,
                                child: Text(locations[locationID]!.name),
                              );
                            }).toList(),
                          ),
                          IconButton(
                              onPressed: () async {
                                var locations = API().getLocations();
                                var code = await scanQRCode(context,
                                    title: "Scan Location Code");
                                if (!locations.containsKey(code)) {
                                  ScaffoldMessenger.of(context).showSnackBar(
                                    SnackBar(
                                        content: Text(
                                            'The location $code does not exist.')),
                                  );
                                  return;
                                }

                                API()
                                    .moveTransaction(widget.transaction.uuid,
                                        selectedLocationID!)
                                    .then(
                                  (x) {
                                    Navigator.of(context).pop();
                                  },
                                );
                                setState(() {});
                              },
                              icon: const Icon(Icons.qr_code))
                        ],
                      ),
                    );
                  },
                );
              },
              icon: const Icon(Icons.move_up))
        ],
      ),
      body: Padding(
        padding: const EdgeInsets.symmetric(horizontal: 18.0),
        child: Column(
          children: [
            Row(
              children: [
                QRCode(
                  data: transaction.uuid,
                  size: 128,
                  eyeStyle: const QREyeStyle(color: Colors.white),
                  dataModuleStyle: const QRDataModuleStyle(color: Colors.white),
                  semanticsLabel: "Transaction UUID",
                ),
                const SizedBox(
                  width: 16.0,
                ),
                Column(
                  mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                  children: [
                    // todo : human names
                    Text(
                      API().getItem(transaction.item).name,
                      style: const TextStyle(
                          fontWeight: FontWeight.bold, fontSize: 28),
                    ),
                    Text(
                      API()
                          .getItem(transaction.item)
                          .variants[transaction.variant]!
                          .name,
                      style: const TextStyle(
                          fontWeight: FontWeight.bold,
                          fontSize: 20,
                          color: Colors.grey),
                    ),
                    const SizedBox(
                      height: 8.0,
                    ),
                    Text("Added: ${tsFormat(transaction.timestamp)}"),
                  ],
                )
              ],
            ),
            const Divider(),
            const SizedBox(
              height: 12.0,
            ),

            if (transaction.expired) const Text("Transaction is Expired!"),

            IconText(Icons.money, transaction.price.toStringAsFixed(2),
                color: Colors.green),

            if (transaction.origin != null)
              IconText(Icons.store, transaction.origin!, color: Colors.blue),

            if (transaction.location != null)
              IconText(Icons.location_city, transaction.location!.name),

            if (transaction.note != null) Text(transaction.note!),

            if (transaction.consumed != null) ...[
              const Divider(),
              Text("Consumed on: ${tsFormat(transaction.consumed!.timestamp)}"),
              IconText(Icons.store, transaction.consumed!.destination,
                  color: Colors.blue),
              IconText(
                  Icons.money, transaction.consumed!.price.toStringAsFixed(2),
                  color: Colors.green),
            ]

            // todo : chart with price history
          ],
        ),
      ),
      floatingActionButton: transaction.consumed == null
          ? FloatingActionButton(
              onPressed: () {
                Navigator.of(context).push(MaterialPageRoute(
                  builder: (context) {
                    return ConsumePage(transaction, reload);
                  },
                ));
              },
              child: const Icon(Icons.receipt_long))
          : null,
    );
  }
}

class TransactionCard extends StatelessWidget {
  final Transaction t;
  final Function refresh;
  final Function(Transaction)? onTap;
  final Function(Transaction)? onLongPress;

  const TransactionCard(this.t, this.refresh,
      {this.onTap, this.onLongPress, super.key});

  @override
  Widget build(BuildContext context) {
    return InkWell(
      onTap: () {
        if (onTap != null) {
          onTap!(t);
          return;
        }

        Navigator.of(context).push(MaterialPageRoute(
          builder: (context) {
            return ConsumePage(t, refresh);
          },
        ));
      },
      onLongPress: () {
        if (onLongPress != null) {
          onLongPress!(t);
          return;
        }

        Navigator.of(context).push(MaterialPageRoute(
          builder: (context) {
            return TransactionPage(t);
          },
        ));
      },
      child: Card(
        color: t.expired ? Colors.red[100] : Colors.black,
        margin: const EdgeInsets.symmetric(vertical: 8, horizontal: 16),
        shape: RoundedRectangleBorder(
          borderRadius: BorderRadius.circular(10),
        ),
        elevation: 4,
        child: Padding(
          padding: const EdgeInsets.all(12),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,
                children: [
                  Row(
                    children: [
                      Text(
                        API().getItem(t.item).name,
                        style: const TextStyle(fontSize: 16),
                      ),
                      const SizedBox(
                        width: 8,
                      ),
                      Text(
                        API().getItem(t.item).variants[t.variant]!.name,
                        style: TextStyle(fontSize: 14, color: Colors.grey[400]),
                      ),
                    ],
                  ),
                  if (t.timestamp != 0)
                    Text(
                      tsFormat(t.timestamp),
                      style: TextStyle(fontSize: 14, color: Colors.grey[700]),
                    ),
                ],
              ),
              if ((t.note ?? "").isNotEmpty) ...[
                const SizedBox(
                  height: 4,
                ),
                Text(t.note!)
              ],
              const SizedBox(
                height: 10,
              ),
              IconText(Icons.money, "${t.price.toStringAsFixed(2)} €",
                  color: Colors.green),
              if (t.origin != null) ...[
                const SizedBox(height: 8),
                IconText(Icons.store, t.origin!, color: Colors.blue)
              ],
              if (t.location != null) ...[
                const SizedBox(
                  height: 8,
                ),
                IconText(Icons.location_city, t.location!.name)
              ]
            ],
          ),
        ),
      ),
    );
  }
}

String tsFormat(int ts) {
  DateTime dateTime = DateTime.fromMillisecondsSinceEpoch(ts * 1000);
  return DateFormat('yyyy-MM-dd HH:mm:ss').format(dateTime);
}

class IconText extends StatelessWidget {
  final IconData icon;
  final String text;
  final Color? color;

  const IconText(this.icon, this.text, {super.key, this.color});

  @override
  Widget build(BuildContext context) {
    return Row(
      children: [
        Icon(icon, size: 18, color: color),
        const SizedBox(width: 6),
        Text(
          text,
          style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold),
          overflow: TextOverflow.fade,
        ),
      ],
    );
  }
}

class TransactionSelectPage extends StatelessWidget {
  final Function(Transaction) onSelect;
  final List<Transaction> selections;
  final List<Transaction>? exclude;

  const TransactionSelectPage(this.selections,
      {super.key, required this.onSelect, this.exclude});

  @override
  Widget build(BuildContext context) {
    var selectionList = [];

    for (var s in selections) {
      if (exclude?.any((x) => x.uuid == s.uuid) ?? false) {
        continue;
      }

      selectionList.add(s);
    }

    return Scaffold(
      appBar: AppBar(
        title: const Text("Select a Transaction"),
      ),
      body: ListView(
          children: selectionList.isEmpty
              ? [
                  const ListTile(
                    title: Center(child: Text("No Transactions available")),
                  )
                ]
              : selectionList
                  .map((x) => TransactionCard(
                        x,
                        () {},
                        onLongPress: (x) {},
                        onTap: (t) {
                          onSelect(t);
                          Navigator.of(context).pop();
                        },
                      ))
                  .toList()),
    );
  }
}