import 'package:cdb_ui/api.dart' as API;
import 'package:cdb_ui/pages/expandable_list.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();
    API.API().getFlows().then(
      (value) {
        setState(() {
          flowInfos = value;
        });
      },
    );
  }

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

  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(key)));
    }

    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(key)));
    }

    return ExpandableList(items);
  }

  @override
  Widget build(BuildContext context) {
    // todo : list currently active

    if (flowInfos == null) {
      return const CircularProgressIndicator();
    }

    return Scaffold(
        appBar: AppBar(
            title: const Text("Flows"),
            bottom: TabBar(
              tabs: const [Text("All"), Text("Produces"), Text("Depends")],
              onTap: (value) {
                setState(() {
                  tabSelection = value;
                });
              },
            )),
        body: switch (tabSelection) {
          0 => listAllFlowInfos(context, flowInfos!),
          1 => listFlowInfoByProduced(context, flowInfos!),
          2 => listFlowInfoByDependant(context, flowInfos!),
          _ => const Text("..."),
        });
  }
}

class FlowInfoPage extends StatelessWidget {
  final API.FlowInfo info;

  const FlowInfoPage(this.info, {super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text(info.name)),
      body: Column(
        children: [
          // todo : ui improve
          if (info.next != null) Text("Next: ${info.next}"),
          if (info.depends.isNotEmpty)
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                const Text("Flow can use: "),
                ...info.depends.map((x) => Text(x)).toList(),
              ],
            ),
          if (info.produces?.isNotEmpty ?? false)
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                const Text("Flow can produce: "),
                ...info.produces!.map((x) => Text(x)).toList(),
              ],
            ),
          const Divider(),
          FutureBuilder(
            future: API.API().getActiveFlowsOf(info.id),
            builder: (context, snapshot) {
              if (!snapshot.hasData) {
                return const CircularProgressIndicator();
              }

              var data = snapshot.data!;

              return ListView(
                  children: data
                      .map((x) => ListTile(
                          title: Text(x.id),
                          onTap: () =>
                              Navigator.of(context).push(MaterialPageRoute(
                                builder: (context) => ActiveFlowPage(x),
                              ))))
                      .toList());
            },
          )
        ],
      ),
    );
  }
}

class ActiveFlowPage extends StatelessWidget {
  late API.Flow flow;

  ActiveFlowPage(this.flow);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        body: Column(
      children: [],
    ));
  }
}