import 'package:cdb_ui/api.dart' as API;
import 'package:cdb_ui/pages/expandable_list.dart';
import 'package:cdb_ui/pages/flow/active_flow_page.dart';
import 'package:cdb_ui/pages/flow/flow_info_page.dart';
import 'package:cdb_ui/pages/supply.dart';
import 'package:flutter/material.dart';

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

  @override
  State<FlowsPage> createState() => _FlowsPageState();
}

class _FlowsPageState extends State<FlowsPage> {
  int tabSelection = 0;
  Map<String, API.FlowInfo>? flowInfos;

  @override
  void initState() {
    super.initState();
    flowInfos = API.API().getFlows();
  }

  Widget flowTile(BuildContext context, API.FlowInfo x) {
    return ListTile(
      title: Text(x.name),
      onTap: () {
        Navigator.of(context).push(MaterialPageRoute(
          builder: (context) => FlowInfoPage(x),
        ));
      },
    );
  }

  Widget listFlowInfoByActive(
      BuildContext context, Map<String, API.FlowInfo> infos) {
    return FutureBuilder(future: () async {
      var included = [];

      for (var key in infos.keys) {
        var active = await API.API().getActiveFlowsOf(key);
        if (active.isNotEmpty) {
          included.add(infos[key]);
        }
      }

      return included;
    }(), builder: (context, snapshot) {
      if (!snapshot.hasData) {
        return const CircularProgressIndicator();
      }

      var included = snapshot.data!;

      return ListView(
          children: included.map((x) => flowTile(context, x)).toList());
    });
  }

  Widget listAllFlowInfos(
      BuildContext context, Map<String, API.FlowInfo> infos) {
    return ListView(
        children: infos.values.map((x) {
      return flowTile(context, x);
    }).toList());
  }

  Widget listFlowInfoByProduced(
      BuildContext context, Map<String, API.FlowInfo> infos) {
    Map<String, List<API.FlowInfo>> producedMapping = {};

    for (var f in infos.values) {
      for (var produces in f.produces ?? []) {
        var item = API.itemVariant(produces).$1;
        producedMapping.putIfAbsent(item, () {
          return [];
        });
        producedMapping[item]!.add(f);
      }
    }

    List<ExpandableListItem> items = [];

    for (var key in producedMapping.keys) {
      var flows = Column(
          children: producedMapping[key]!.map((x) {
        return flowTile(context, x);
      }).toList());
      items.add(ExpandableListItem(
          body: flows, header: Text(API.API().getItem(key).name)));
    }

    return ExpandableList(items);
  }

  Widget listFlowInfoByDependant(
      BuildContext context, Map<String, API.FlowInfo> infos) {
    Map<String, List<API.FlowInfo>> dependsMapping = {};

    for (var f in infos.values) {
      for (var produces in f.depends) {
        var item = API.itemVariant(produces).$1;
        // todo : add only if item is in inventory
        dependsMapping.putIfAbsent(item, () {
          return [];
        });
        dependsMapping[item]!.add(f);
      }
    }

    List<ExpandableListItem> items = [];

    for (var key in dependsMapping.keys) {
      var flows = Column(
          children: dependsMapping[key]!.map((x) {
        return flowTile(context, x);
      }).toList());
      items.add(ExpandableListItem(
          body: flows, header: Text(API.API().getItem(key).name)));
    }

    return ExpandableList(items);
  }

  @override
  Widget build(BuildContext context) {
    if (flowInfos == null) {
      return const CircularProgressIndicator();
    }

    return DefaultTabController(
        length: 4,
        child: Scaffold(
          appBar: AppBar(
              title: const Text("Flows"),
              bottom: TabBar(
                tabs: const [
                  Tab(text: "All"),
                  Tab(text: "Produces"),
                  Tab(text: "Depends"),
                  Tab(text: "Active")
                ],
                onTap: (value) {
                  setState(() {
                    tabSelection = value;
                  });
                },
              )),
          body: switch (tabSelection) {
            0 => listAllFlowInfos(context, flowInfos!),
            1 => listFlowInfoByProduced(context, flowInfos!),
            2 => listFlowInfoByDependant(context, flowInfos!),
            3 => listFlowInfoByActive(context, flowInfos!),
            _ => const Text("..."),
          },
          floatingActionButton: FloatingActionButton(
            onPressed: () async {
              // scan flow code
              var code = await scanQRCode(context, title: "Scan Flow Code");

              API.API().getFlow(code!).then((flow) {
                var info = API.API().getFlowInfo(flow.kind);
                Navigator.of(context).push(MaterialPageRoute(
                  builder: (context) {
                    return ActiveFlowPage(flow, info);
                  },
                ));
              });
            },
            child: const Icon(Icons.qr_code),
          ),
        ));
  }
}