import i18next from "i18next";
import { action, computed, runInAction, makeObservable } from "mobx";
import containsAny from "../../../Core/containsAny";
import filterOutUndefined from "../../../Core/filterOutUndefined";
import isDefined from "../../../Core/isDefined";
import isReadOnlyArray from "../../../Core/isReadOnlyArray";
import replaceUnderscores from "../../../Core/replaceUnderscores";
import runLater from "../../../Core/runLater";
import TerriaError from "../../../Core/TerriaError";
import CatalogMemberMixin from "../../../ModelMixins/CatalogMemberMixin";
import GetCapabilitiesMixin from "../../../ModelMixins/GetCapabilitiesMixin";
import GroupMixin from "../../../ModelMixins/GroupMixin";
import UrlMixin from "../../../ModelMixins/UrlMixin";
import ModelReference from "../../../Traits/ModelReference";
import { InfoSectionTraits } from "../../../Traits/TraitsClasses/CatalogMemberTraits";
import WebMapServiceCatalogGroupTraits from "../../../Traits/TraitsClasses/WebMapServiceCatalogGroupTraits";
import CommonStrata from "../../Definition/CommonStrata";
import CreateModel from "../../Definition/CreateModel";
import createStratumInstance from "../../Definition/createStratumInstance";
import LoadableStratum from "../../Definition/LoadableStratum";
import { BaseModel } from "../../Definition/Model";
import StratumFromTraits from "../../Definition/StratumFromTraits";
import updateModelFromJson from "../../Definition/updateModelFromJson";
import CatalogGroup from "../CatalogGroup";
import proxyCatalogItemUrl from "../proxyCatalogItemUrl";
import WebMapServiceCapabilities, {
  CapabilitiesLayer
} from "./WebMapServiceCapabilities";
import WebMapServiceCatalogItem from "./WebMapServiceCatalogItem";

class GetCapabilitiesStratum extends LoadableStratum(
  WebMapServiceCatalogGroupTraits
) {
  static async load(
    catalogItem: WebMapServiceCatalogGroup
  ): Promise<GetCapabilitiesStratum> {
    if (catalogItem.getCapabilitiesUrl === undefined) {
      throw new TerriaError({
        title: i18next.t("models.webMapServiceCatalogGroup.missingUrlTitle"),
        message: i18next.t("models.webMapServiceCatalogGroup.missingUrlMessage")
      });
    }

    const capabilities = await WebMapServiceCapabilities.fromUrl(
      proxyCatalogItemUrl(
        catalogItem,
        catalogItem.getCapabilitiesUrl,
        catalogItem.getCapabilitiesCacheDuration
      )
    );
    return new GetCapabilitiesStratum(catalogItem, capabilities);
  }

  constructor(
    readonly catalogGroup: WebMapServiceCatalogGroup,
    readonly capabilities: WebMapServiceCapabilities
  ) {
    super();
    makeObservable(this);
  }

  duplicateLoadableStratum(model: BaseModel): this {
    return new GetCapabilitiesStratum(
      model as WebMapServiceCatalogGroup,
      this.capabilities
    ) as this;
  }

  @computed get name() {
    if (
      this.capabilities &&
      this.capabilities.Service &&
      this.capabilities.Service.Title
    ) {
      return replaceUnderscores(this.capabilities.Service.Title);
    }
  }

  @computed get info() {
    const result: StratumFromTraits<InfoSectionTraits>[] = [];

    const service = this.capabilities && this.capabilities.Service;
    if (service) {
      // Show the service abstract if there is one and if it isn't the Geoserver default "A compliant implementation..."
      if (
        service &&
        service.Abstract &&
        !containsAny(
          service.Abstract,
          WebMapServiceCatalogItem.abstractsToIgnore
        )
      ) {
        result.push(
          createStratumInstance(InfoSectionTraits, {
            name: i18next.t("models.webMapServiceCatalogGroup.abstract"),
            content: this.capabilities.Service.Abstract
          })
        );
      }

      // Show the Access Constraints if it isn't "none" (because that's the default, and usually a lie).
      if (
        service &&
        service.AccessConstraints &&
        !/^none$/i.test(service.AccessConstraints)
      ) {
        result.push(
          createStratumInstance(InfoSectionTraits, {
            name: i18next.t(
              "models.webMapServiceCatalogGroup.accessConstraints"
            ),
            content: this.capabilities.Service.AccessConstraints
          })
        );
      }

      // Show the Fees if it isn't "none".
      if (service && service.Fees && !/^none$/i.test(service.Fees)) {
        result.push(
          createStratumInstance(InfoSectionTraits, {
            name: i18next.t("models.webMapServiceCatalogGroup.fees"),
            content: this.capabilities.Service.Fees
          })
        );
      }
    }

    return result;
  }

  @computed
  get members(): ModelReference[] {
    return filterOutUndefined(
      this.topLevelLayers.map((layer) => this.getLayerId(layer))
    );
  }

  get topLevelLayers(): readonly CapabilitiesLayer[] {
    if (this.catalogGroup.flatten) {
      return this.capabilities.allLayers;
    } else {
      let rootLayers: readonly CapabilitiesLayer[] =
        this.capabilities.rootLayers;
      while (
        rootLayers &&
        rootLayers.length === 1 &&
        rootLayers[0].Name === undefined
      ) {
        const subLayer:
          | CapabilitiesLayer
          | readonly CapabilitiesLayer[]
          | undefined = rootLayers[0].Layer;
        if (subLayer && isReadOnlyArray(subLayer)) {
          rootLayers = subLayer;
        } else if (subLayer) {
          rootLayers = [subLayer as CapabilitiesLayer];
        } else {
          break;
        }
      }
      return rootLayers;
    }
  }

  @action
  createMembersFromLayers() {
    this.topLevelLayers.forEach((layer) => this.createMemberFromLayer(layer));
  }

  @action
  createMemberFromLayer(layer: CapabilitiesLayer, parentLayerId?: string) {
    const layerId = this.getLayerId(layer, parentLayerId);

    if (!layerId) {
      return;
    }

    // If has nested layers -> create model for CatalogGroup
    if (layer.Layer) {
      // Create nested layers
      let members: CapabilitiesLayer[];
      if (Array.isArray(layer.Layer)) {
        members = layer.Layer;
      } else {
        members = [layer.Layer as CapabilitiesLayer];
      }

      members.forEach((member) => this.createMemberFromLayer(member, layerId));

      // Create group
      const existingModel = this.catalogGroup.terria.getModelById(
        CatalogGroup,
        layerId
      );

      let model: CatalogGroup;
      if (existingModel === undefined) {
        model = new CatalogGroup(layerId, this.catalogGroup.terria);
        try {
          // Sometimes WMS Layers have duplicate names
          // At the moment we ignore duplicate layers
          this.catalogGroup.terria.addModel(
            model,
            this.getLayerShareKeys(layer, layerId)
          );
        } catch (e) {
          TerriaError.from(e, "Failed to add CatalogGroup").log();
          return;
        }
      } else {
        model = existingModel;
      }

      model.setTrait(CommonStrata.definition, "name", layer.Title);
      model.setTrait(
        CommonStrata.definition,
        "members",
        filterOutUndefined(
          members.map((member) => this.getLayerId(member, layerId))
        )
      );

      // Set group `info` trait if applicable
      if (
        layer &&
        layer.Abstract &&
        !containsAny(layer.Abstract, WebMapServiceCatalogItem.abstractsToIgnore)
      ) {
        model.setTrait(CommonStrata.definition, "info", [
          createStratumInstance(InfoSectionTraits, {
            name: i18next.t("models.webMapServiceCatalogGroup.abstract"),
            content: layer.Abstract
          })
        ]);
      }

      return;
    }

    // We can only request WMS layers if `Name` is defined
    if (!isDefined(layer.Name)) return;

    // No nested layers -> create model for WebMapServiceCatalogItem
    const existingModel = this.catalogGroup.terria.getModelById(
      WebMapServiceCatalogItem,
      layerId
    );

    let model: WebMapServiceCatalogItem;
    if (existingModel === undefined) {
      model = new WebMapServiceCatalogItem(layerId, this.catalogGroup.terria);

      try {
        // Sometimes WMS Layers have duplicate names
        // At the moment we ignore duplicate layers
        this.catalogGroup.terria.addModel(
          model,
          this.getLayerShareKeys(layer, layerId)
        );
      } catch (e) {
        TerriaError.from(e, "Failed to add WebMapServiceCatalogItem").log();
        return;
      }
    } else {
      model = existingModel;
    }

    // Replace the stratum inherited from the parent group.
    model.strata.delete(CommonStrata.definition);

    model.setTrait(CommonStrata.definition, "name", layer.Title);
    model.setTrait(CommonStrata.definition, "url", this.catalogGroup.url);
    model._webMapServiceCatalogGroup = this.catalogGroup;
    model.setTrait(
      CommonStrata.definition,
      "getCapabilitiesUrl",
      this.catalogGroup.getCapabilitiesUrl
    );
    model.setTrait(
      CommonStrata.definition,
      "getCapabilitiesCacheDuration",
      this.catalogGroup.getCapabilitiesCacheDuration
    );
    model.setTrait(CommonStrata.definition, "layers", layer.Name);

    // if user defined following properties on the group level we should pass them to all group members
    model.setTrait(
      CommonStrata.definition,
      "hideSource",
      this.catalogGroup.hideSource
    );
    model.setTrait(
      CommonStrata.definition,
      "isOpenInWorkbench",
      this.catalogGroup.isOpenInWorkbench
    );
    model.setTrait(
      CommonStrata.definition,
      "isExperiencingIssues",
      this.catalogGroup.isExperiencingIssues
    );
    model.setTrait(
      CommonStrata.definition,
      "hideLegendInWorkbench",
      this.catalogGroup.hideLegendInWorkbench
    );

    // Copy over ExportWebCoverageTraits if `linkedWcsUrl` has been set
    // See WebMapServiceCatalogGroupTraits.perLayerLinkedWcs for more info
    if (this.catalogGroup.perLayerLinkedWcs?.linkedWcsUrl) {
      updateModelFromJson(model, CommonStrata.definition, {
        // Copy over all perLayerLinkedWcs objects
        ...this.catalogGroup.traits.perLayerLinkedWcs.toJson(
          this.catalogGroup.perLayerLinkedWcs
        ),
        // Override linkedWcsCoverage with layer.Name
        linkedWcsCoverage: layer.Name
      }).logError(
        `Failed to set \`perLayerLinkedWcs\` for WMS layer ${layer.Title}`
      );
    }

    model.createGetCapabilitiesStratumFromParent(this.capabilities);
  }

  getLayerId(layer: CapabilitiesLayer, parentLayerId?: string) {
    if (!isDefined(this.catalogGroup.uniqueId) && !isDefined(parentLayerId)) {
      return;
    }
    return `${parentLayerId ?? this.catalogGroup.uniqueId}/${
      layer.Name ?? layer.Title
    }`;
  }

  /** For backward-compatibility.
   * Previously we have used the following IDs
   * - `WMS Group Catalog ID/WMS Layer Name` - regardless of nesting
   * - `WMS Group Catalog ID/WMS Layer Title`
   */
  getLayerShareKeys(layer: CapabilitiesLayer, layerId: string) {
    const shareKeys: string[] = [];

    if (layerId !== `${this.catalogGroup.uniqueId}/${layer.Name}`)
      shareKeys.push(`${this.catalogGroup.uniqueId}/${layer.Name}`);

    if (isDefined(layer.Name) && layer.Title !== layer.Name)
      shareKeys.push(`${this.catalogGroup.uniqueId}/${layer.Title}`);

    return shareKeys;
  }
}

/**
 * Creates an item in the catalog for each available WMS layer.
 * Note: To present a single layer in the catalog you can also use `WebMapServiceCatalogItem`.
 * @public
 * @example
 * {
 *   "type": "wms-group",
 *   "name": "Digital Earth Australia",
 *   "url": "https://ows.services.dea.ga.gov.au",
 * }
 */
export default class WebMapServiceCatalogGroup extends GetCapabilitiesMixin(
  UrlMixin(
    GroupMixin(CatalogMemberMixin(CreateModel(WebMapServiceCatalogGroupTraits)))
  )
) {
  static readonly type = "wms-group";

  get type() {
    return WebMapServiceCatalogGroup.type;
  }

  protected async forceLoadMetadata(): Promise<void> {
    let getCapabilitiesStratum = this.strata.get(
      GetCapabilitiesMixin.getCapabilitiesStratumName
    ) as GetCapabilitiesStratum | undefined;
    if (getCapabilitiesStratum === undefined) {
      getCapabilitiesStratum = await GetCapabilitiesStratum.load(this);
      runInAction(() => {
        this.strata.set(
          GetCapabilitiesMixin.getCapabilitiesStratumName,
          getCapabilitiesStratum!
        );
      });
    }
  }

  protected async forceLoadMembers(): Promise<void> {
    const getCapabilitiesStratum = this.strata.get(
      GetCapabilitiesMixin.getCapabilitiesStratumName
    ) as GetCapabilitiesStratum | undefined;
    if (getCapabilitiesStratum !== undefined) {
      await runLater(() => getCapabilitiesStratum!.createMembersFromLayers());
    }
  }

  protected get defaultGetCapabilitiesUrl(): string | undefined {
    if (this.uri) {
      return this.uri
        .clone()
        .setSearch({
          service: "WMS",
          version: "1.3.0",
          request: "GetCapabilities"
        })
        .toString();
    } else {
      return undefined;
    }
  }
}