import "package:flutter/material.dart";

import "package:font_awesome_flutter/font_awesome_flutter.dart";

import "package:inventree/app_colors.dart";
import "package:inventree/barcode.dart";
import "package:inventree/inventree/stock.dart";
import "package:inventree/inventree/part.dart";
import "package:inventree/widget/dialogs.dart";
import "package:inventree/widget/location_display.dart";
import "package:inventree/widget/part_detail.dart";
import "package:inventree/widget/progress.dart";
import "package:inventree/widget/refreshable_state.dart";
import "package:inventree/widget/snacks.dart";
import "package:inventree/widget/stock_item_history.dart";
import "package:inventree/widget/stock_item_test_results.dart";
import "package:inventree/widget/stock_notes.dart";
import "package:inventree/l10.dart";
import "package:inventree/api.dart";
import "package:inventree/api_form.dart";
import "package:inventree/preferences.dart";


class StockDetailWidget extends StatefulWidget {

  const StockDetailWidget(this.item, {Key? key}) : super(key: key);

  final InvenTreeStockItem item;

  @override
  _StockItemDisplayState createState() => _StockItemDisplayState(item);
}


class _StockItemDisplayState extends RefreshableState<StockDetailWidget> {

  _StockItemDisplayState(this.item);

  @override
  String getAppBarTitle(BuildContext context) => L10().stockItem;

  bool stockShowHistory = false;

  @override
  List<Widget> getAppBarActions(BuildContext context) {

    List<Widget> actions = [];

    if (InvenTreeAPI().checkPermission("stock", "view")) {
      actions.add(
        IconButton(
          icon: FaIcon(FontAwesomeIcons.globe),
          onPressed: _openInvenTreePage,
        )
      );
    }

    if (InvenTreeAPI().supportsMixin("locate")) {
      actions.add(
        IconButton(
          icon: FaIcon(FontAwesomeIcons.searchLocation),
          tooltip: L10().locateItem,
          onPressed: () async {
            InvenTreeAPI().locateItemOrLocation(context, item: item.pk);
          },
        )
      );
    }

    if (InvenTreeAPI().checkPermission("stock", "change")) {
      actions.add(
          IconButton(
            icon: FaIcon(FontAwesomeIcons.edit),
            tooltip: L10().edit,
            onPressed: () { _editStockItem(context); },
          )
      );
    }

    return actions;
  }

  Future<void> _openInvenTreePage() async {
    item.goToInvenTreePage();
  }

  // StockItem object
  final InvenTreeStockItem item;

  // Is label printing enabled for this StockItem?
  // This will be determined when the widget is loaded
  List<Map<String, dynamic>> labels = [];

  // Part object
  InvenTreePart? part;

  @override
  Future<void> onBuild(BuildContext context) async {

    // Load part data if not already loaded
    if (part == null) {
      refresh(context);
    }
  }

  @override
  Future<void> request(BuildContext context) async {

    final bool result = await item.reload();

    stockShowHistory = await InvenTreeSettingsManager().getValue(INV_STOCK_SHOW_HISTORY, false) as bool;

    // Could not load this stock item for some reason
    // Perhaps it has been depleted?
    if (!result || item.pk == -1) {
      Navigator.of(context).pop();
    }

    // Request part information
    part = await InvenTreePart().get(item.partId) as InvenTreePart?;

    // Request test results (async)
    item.getTestResults().then((value) {
      setState(() {
        // Update
      });
    });

    // Request information on labels available for this stock item
    if (InvenTreeAPI().pluginsEnabled()) {
      _getLabels();
    }
  }

  Future <void> _getLabels() async {
    // Clear the existing labels list
    labels.clear();

    // If the server does not support label printing, don't bother!
    if (!InvenTreeAPI().supportsMixin("labels")) {
      return;
    }

    InvenTreeAPI().get(
        "/label/stock/",
        params: {
          "enabled": "true",
          "item": "${item.pk}",
        },
    ).then((APIResponse response) {
      if (response.isValid() && response.statusCode == 200) {
        for (var label in response.data) {
          if (label is Map<String, dynamic>) {
            labels.add(label);
          }
        }

        setState(() {
        });
      }
    });
  }

  /// Delete the stock item from the database
  Future<void> _deleteItem(BuildContext context) async {

    confirmationDialog(
      L10().stockItemDelete,
      L10().stockItemDeleteConfirm,
      icon: FontAwesomeIcons.trashAlt,
      onAccept: () async {
        final bool result = await item.delete();
        
        if (result) {
          Navigator.of(context).pop();
          showSnackIcon(L10().stockItemDeleteSuccess, success: true);
        } else {
          showSnackIcon(L10().stockItemDeleteFailure, success: false);
        }
      },
    );

  }

  /// Opens a popup dialog allowing user to select a label for printing
  Future <void> _printLabel(BuildContext context) async {

    var plugins = InvenTreeAPI().getPlugins(mixin: "labels");

    dynamic initial_label;
    dynamic initial_plugin;

    List<Map<String, dynamic>> label_options = [];
    List<Map<String, dynamic>> plugin_options = [];

    for (var label in labels) {
      label_options.add({
        "display_name": label["description"],
        "value": label["pk"],
      });
    }

    for (var plugin in plugins) {
      plugin_options.add({
        "display_name": plugin.humanName,
        "value": plugin.key,
      });
    }

    if (labels.length == 1) {
      initial_label =  labels.first["pk"];
    }

    if (plugins.length == 1) {
      initial_plugin = plugins.first.key;
    }

    Map<String, dynamic> fields = {
      "label": {
        "label": L10().labelTemplate,
        "type": "choice",
        "value": initial_label,
        "choices": label_options,
        "required": true,
      },
      "plugin": {
        "label": L10().pluginPrinter,
        "type": "choice",
        "value": initial_plugin,
        "choices": plugin_options,
        "required": true,
      }
    };

    launchApiForm(
      context,
      L10().printLabel,
      "",
      fields,
      icon: FontAwesomeIcons.print,
      onSuccess: (Map<String, dynamic> data) async {
        int labelId = (data["label"] ?? -1) as int;
        String pluginKey = (data["plugin"] ?? "") as String;

        if (labelId != -1 && pluginKey.isNotEmpty) {
          String url = "/label/stock/${labelId}/print/?item=${item.pk}&plugin=${pluginKey}";

          InvenTreeAPI().get(url).then((APIResponse response) {
            if (response.isValid() && response.statusCode == 200) {
              showSnackIcon(
                L10().printLabelSuccess,
                success: true
              );
            } else {
              showSnackIcon(
                L10().printLabelFailure,
                success: false,
              );
            }
          });
        }
      },
    );
  }

  Future <void> _editStockItem(BuildContext context) async {

    var fields = InvenTreeStockItem().formFields();

    // Some fields we don't want to edit!
    fields.remove("part");
    fields.remove("quantity");
    fields.remove("location");

    item.editForm(
      context,
      L10().editItem,
      fields: fields,
      onSuccess: (data) async {
        refresh(context);
        showSnackIcon(L10().stockItemUpdated, success: true);
      }
    );

  }

  /*
   * Launch a dialog to 'add' quantity to this StockItem
   */
  Future <void> _addStockDialog() async {

    Map<String, dynamic> fields = {
      "pk": {
        "parent": "items",
        "nested": true,
        "hidden": true,
        "value": item.pk,
      },
      "quantity": {
        "parent": "items",
        "nested": true,
        "value": 0,
      },
      "notes": {},
    };

    launchApiForm(
      context,
      L10().addStock,
      InvenTreeStockItem.addStockUrl(),
      fields,
      method: "POST",
      icon: FontAwesomeIcons.plusCircle,
      onSuccess: (data) async {
        _stockUpdateMessage(true);
        refresh(context);
      }
    );
  }

  void _stockUpdateMessage(bool result) {

    if (result) {
      showSnackIcon(L10().stockItemUpdated, success: true);
    }
  }

  /*
   * Launch a dialog to 'remove' quantity from this StockItem
   */
  void _removeStockDialog() {

    Map<String, dynamic> fields = {
      "pk": {
        "parent": "items",
        "nested": true,
        "hidden": true,
        "value": item.pk,
      },
      "quantity": {
        "parent": "items",
        "nested": true,
        "value": 0,
      },
      "notes": {},
    };

    launchApiForm(
        context,
        L10().removeStock,
        InvenTreeStockItem.removeStockUrl(),
        fields,
        method: "POST",
        icon: FontAwesomeIcons.minusCircle,
        onSuccess: (data) async {
          _stockUpdateMessage(true);
          refresh(context);
        }
    );
  }

  Future <void> _countStockDialog() async {

    Map<String, dynamic> fields = {
      "pk": {
        "parent": "items",
        "nested": true,
        "hidden": true,
        "value": item.pk,
      },
      "quantity": {
        "parent": "items",
        "nested": true,
        "value": item.quantity,
      },
      "notes": {},
    };

    launchApiForm(
        context,
        L10().countStock,
        InvenTreeStockItem.countStockUrl(),
        fields,
        method: "POST",
        icon: FontAwesomeIcons.clipboardCheck,
        onSuccess: (data) async {
          _stockUpdateMessage(true);
          refresh(context);
        }
    );
  }


  Future<void> _unassignBarcode(BuildContext context) async {

    final bool result = await item.update(values: {"uid": ""});

    if (result) {
      showSnackIcon(
        L10().stockItemUpdateSuccess,
        success: true
      );
    } else {
      showSnackIcon(
        L10().stockItemUpdateFailure,
        success: false,
      );
    }

    refresh(context);
  }


  /*
   * Launches an API Form to transfer this stock item to a new location
   */
  Future <void> _transferStockDialog(BuildContext context) async {

    Map<String, dynamic> fields = {
      "pk": {
        "parent": "items",
        "nested": true,
        "hidden": true,
        "value": item.pk,
      },
      "quantity": {
        "parent": "items",
        "nested": true,
        "value": item.quantity,
      },
      "location": {},
      "notes": {},
    };

    if (item.isSerialized()) {
      // Prevent editing of 'quantity' field if the item is serialized
      fields["quantity"]["hidden"] = true;
    }

    launchApiForm(
        context,
        L10().transferStock,
        InvenTreeStockItem.transferStockUrl(),
        fields,
        method: "POST",
        icon: FontAwesomeIcons.dolly,
        onSuccess: (data) async {
          _stockUpdateMessage(true);
          refresh(context);
        }
    );
  }

  Widget headerTile() {
    return Card(
      child: ListTile(
        title: Text("${item.partName}"),
        subtitle: Text("${item.partDescription}"),
        leading: InvenTreeAPI().getImage(item.partImage),
        trailing: Text(
          item.statusLabel(context),
          style: TextStyle(
            color: item.statusColor
          )
        ),
        onTap: () {
          if (item.partId > 0) {
            InvenTreePart().get(item.partId).then((var part) {
              if (part is InvenTreePart) {
                Navigator.push(context, MaterialPageRoute(builder: (context) => PartDetailWidget(part)));
              }
            });
          }
        },
        //trailing: Text(item.serialOrQuantityDisplay()),
      )
    );
  }

  /*
   * Construct a list of detail elements about this StockItem.
   * The number of elements may vary depending on the StockItem details
   */
  List<Widget> detailTiles() {
    List<Widget> tiles = [];

    // Image / name / description
    tiles.add(headerTile());

    if (loading) {
      tiles.add(progressIndicator());
      return tiles;
    }

    // Quantity information
    if (item.isSerialized()) {
      tiles.add(
          ListTile(
            title: Text(L10().serialNumber),
            leading: FaIcon(FontAwesomeIcons.hashtag),
            trailing: Text("${item.serialNumber}"),
          )
      );
    } else {
      tiles.add(
          ListTile(
            title: Text(L10().quantity),
            leading: FaIcon(FontAwesomeIcons.cubes),
            trailing: Text("${item.quantityString()}"),
          )
      );
    }

    // Location information
    if ((item.locationId > 0) && (item.locationName.isNotEmpty)) {
      tiles.add(
          ListTile(
            title: Text(L10().stockLocation),
            subtitle: Text("${item.locationPathString}"),
            leading: FaIcon(
              FontAwesomeIcons.mapMarkerAlt,
              color: COLOR_CLICK,
            ),
            onTap: () {
              if (item.locationId > 0) {
                InvenTreeStockLocation().get(item.locationId).then((var loc) {

                  if (loc is InvenTreeStockLocation) {
                    Navigator.push(context, MaterialPageRoute(
                        builder: (context) => LocationDisplayWidget(loc)));
                  }
                });
              }
            },
          ),
      );
    } else {
      tiles.add(
          ListTile(
            title: Text(L10().stockLocation),
            leading: FaIcon(FontAwesomeIcons.mapMarkerAlt),
            subtitle: Text(L10().locationNotSet),
          )
      );
    }

    if (item.isBuilding) {
      tiles.add(
        ListTile(
          title: Text(L10().inProduction),
          leading: FaIcon(FontAwesomeIcons.tools),
          subtitle: Text(L10().inProductionDetail),
          onTap: () {
            // TODO: Click through to the "build order"
          },
        )
      );
    }

    if (item.batch.isNotEmpty) {
      tiles.add(
        ListTile(
          title: Text(L10().batchCode),
          subtitle: Text(item.batch),
          leading: FaIcon(FontAwesomeIcons.layerGroup),
        )
      );
    }

    if (item.packaging.isNotEmpty) {
      tiles.add(
        ListTile(
          title: Text(L10().packaging),
          subtitle: Text(item.packaging),
          leading: FaIcon(FontAwesomeIcons.box),
        )
      );
    }

    // Last update?
    if (item.updatedDateString.isNotEmpty) {

      tiles.add(
        ListTile(
          title: Text(L10().lastUpdated),
          subtitle: Text(item.updatedDateString),
          leading: FaIcon(FontAwesomeIcons.calendarAlt)
        )
      );
    }

    // Stocktake?
    if (item.stocktakeDateString.isNotEmpty) {
      tiles.add(
        ListTile(
          title: Text(L10().lastStocktake),
          subtitle: Text(item.stocktakeDateString),
          leading: FaIcon(FontAwesomeIcons.calendarAlt)
        )
      );
    }

    // Supplier part?
    // TODO: Display supplier part info page?
    /*
    if (item.supplierPartId > 0) {
      tiles.add(
        ListTile(
          title: Text("${item.supplierName}"),
          subtitle: Text("${item.supplierSKU}"),
          leading: FaIcon(FontAwesomeIcons.industry),
          trailing: InvenTreeAPI().getImage(item.supplierImage),
          onTap: null,
        )
      );
    }
     */

    if (item.link.isNotEmpty) {
      tiles.add(
        ListTile(
          title: Text("${item.link}"),
          leading: FaIcon(FontAwesomeIcons.link, color: COLOR_CLICK),
          onTap: () {
            item.openLink();
          },
        )
      );
    }

    if ((item.testResultCount > 0) || (part?.isTrackable ?? false)) {
      tiles.add(
          ListTile(
              title: Text(L10().testResults),
              leading: FaIcon(FontAwesomeIcons.tasks, color: COLOR_CLICK),
              trailing: Text("${item.testResultCount}"),
              onTap: () {
                Navigator.push(
                    context,
                    MaterialPageRoute(
                        builder: (context) => StockItemTestResultsWidget(item))
                ).then((ctx) {
                  refresh(context);
                });
              }
          )
      );
    }

    if (item.hasPurchasePrice) {
      tiles.add(
        ListTile(
          title: Text(L10().purchasePrice),
          leading: FaIcon(FontAwesomeIcons.dollarSign),
          trailing: Text(item.purchasePrice),
        )
      );
    }

    // TODO - Is this stock item linked to a PurchaseOrder?

    if (stockShowHistory && item.trackingItemCount > 0) {
      tiles.add(
        ListTile(
          title: Text(L10().history),
          leading: FaIcon(FontAwesomeIcons.history, color: COLOR_CLICK),
          trailing: Text("${item.trackingItemCount}"),
          onTap: () {
            Navigator.push(
              context,
              MaterialPageRoute(
                builder: (context) => StockItemHistoryWidget(item))
              ).then((ctx) {
                refresh(context);
            });
          },
        )
      );
    }

    // Notes field
    tiles.add(
      ListTile(
        title: Text(L10().notes),
        leading: FaIcon(FontAwesomeIcons.stickyNote, color: COLOR_CLICK),
        onTap: () {
          Navigator.push(
            context,
            MaterialPageRoute(builder: (context) => StockNotesWidget(item))
          );
          // TODO: Load notes in markdown viewer widget
          // TODO: Make this widget editable?
        }
      )
    );

    return tiles;
  }

  List<Widget> actionTiles(BuildContext context) {
    List<Widget> tiles = [];

    tiles.add(headerTile());

    // First check that the user has the required permissions to adjust stock
    if (!InvenTreeAPI().checkPermission("stock", "change")) {
      tiles.add(
        ListTile(
          title: Text(L10().permissionRequired),
          leading: FaIcon(FontAwesomeIcons.userTimes)
        )
      );

      tiles.add(
        ListTile(
          subtitle: Text(L10().permissionAccountDenied),
        )
      );

      return tiles;
    }

    // "Count" is not available for serialized stock
    if (!item.isSerialized()) {
      tiles.add(
          ListTile(
              title: Text(L10().countStock),
              leading: FaIcon(FontAwesomeIcons.checkCircle, color: COLOR_CLICK),
              onTap: _countStockDialog,
              trailing: Text(item.quantityString(includeUnits: true)),
          )
      );

      tiles.add(
          ListTile(
              title: Text(L10().removeStock),
              leading: FaIcon(FontAwesomeIcons.minusCircle, color: COLOR_CLICK),
              onTap: _removeStockDialog,
          )
      );

      tiles.add(
          ListTile(
              title: Text(L10().addStock),
              leading: FaIcon(FontAwesomeIcons.plusCircle, color: COLOR_CLICK),
              onTap: _addStockDialog,
          )
      );
    }

    tiles.add(
      ListTile(
        title: Text(L10().transferStock),
        leading: FaIcon(FontAwesomeIcons.exchangeAlt, color: COLOR_CLICK),
        onTap: () { _transferStockDialog(context); },
      )
    );

    // Scan item into a location
    tiles.add(
      ListTile(
        title: Text(L10().scanIntoLocation),
        leading: FaIcon(FontAwesomeIcons.exchangeAlt, color: COLOR_CLICK),
        trailing: Icon(Icons.qr_code_scanner),
        onTap: () {
          Navigator.push(
            context,
            MaterialPageRoute(builder: (context) => InvenTreeQRView(StockItemScanIntoLocationHandler(item)))
          ).then((ctx) {
            refresh(context);
          });
        },
      )
    );

    // Add or remove custom barcode
    if (item.uid.isEmpty) {
      tiles.add(
        ListTile(
          title: Text(L10().barcodeAssign),
          leading: Icon(Icons.qr_code),
          trailing: Icon(Icons.qr_code_scanner),
          onTap: () {

            var handler = UniqueBarcodeHandler((String hash) {
              item.update(
                values: {
                  "uid": hash,
                }
              ).then((result) {
                if (result) {
                  barcodeSuccessTone();

                  showSnackIcon(
                    L10().barcodeAssigned,
                    success: true,
                    icon: Icons.qr_code,
                  );

                  refresh(context);
                }
              });
            });

            Navigator.push(
              context,
              MaterialPageRoute(builder: (context) => InvenTreeQRView(handler))
            );
          }
        )
      );
    } else {
      tiles.add(
        ListTile(
          title: Text(L10().barcodeUnassign),
          leading: Icon(Icons.qr_code, color: COLOR_CLICK),
          onTap: () {
            _unassignBarcode(context);
          }
        )
      );
    }

    // Print label (if label printing plugins exist)
    if (labels.isNotEmpty) {
      tiles.add(
        ListTile(
          title: Text(L10().printLabel),
          leading: FaIcon(FontAwesomeIcons.print, color: COLOR_CLICK),
          onTap: () {
            _printLabel(context);
          },
        ),
      );
    }

    // If the user has permission to delete this stock item
    if (InvenTreeAPI().checkPermission("stock", "delete")) {
      tiles.add(
        ListTile(
          title: Text("Delete Stock Item"),
          leading: FaIcon(FontAwesomeIcons.trashAlt, color: COLOR_DANGER),
          onTap: () {
            _deleteItem(context);
          },
        )
      );
    }

    return tiles;
  }

  @override
  Widget getBottomNavBar(BuildContext context) {
    return BottomNavigationBar(
      currentIndex: tabIndex,
      onTap: onTabSelectionChanged,
      items: <BottomNavigationBarItem> [
        BottomNavigationBarItem(
          icon: FaIcon(FontAwesomeIcons.infoCircle),
          label: L10().details,
        ),
        BottomNavigationBarItem(
          icon: FaIcon(FontAwesomeIcons.wrench),
          label: L10().actions,        ),
      ]
    );
  }

  Widget getSelectedWidget(int index) {
    switch (index) {
      case 0:
        return ListView(
          children: ListTile.divideTiles(
            context: context,
            tiles: detailTiles()
          ).toList(),
        );
      case 1:
        return ListView(
          children: ListTile.divideTiles(
            context: context,
            tiles: actionTiles(context)
          ).toList()
        );
      default:
        return ListView();
    }
  }

  @override
  Widget getBody(BuildContext context) {
    return getSelectedWidget(tabIndex);
  }
}