Feature: be able to set a default background layer, fix background layer query parameter

src/Logic/State/UserRelatedState.ts

@@ -17,6 +17,7 @@ import FeatureSwitchState from "./FeatureSwitchState"
 import Constants from "../../Models/Constants"
 import { QueryParameters } from "../Web/QueryParameters"
 import { ThemeMetaTagging } from "./UserSettingsMetaTagging"
+import { MapProperties } from "../../Models/MapProperties";
 
 /**
  * The part of the state which keeps track of user-related stuff, e.g. the OSM-connection,
@@ -41,6 +42,7 @@ export default class UserRelatedState {
     public readonly fixateNorth: UIEventSource<undefined | "yes">
     public readonly homeLocation: FeatureSource
     public readonly language: UIEventSource<string>
+    public readonly preferredBackgroundLayer: UIEventSource<string | "photo" | "map" | "osmbasedmap" | undefined>
     /**
      * The number of seconds that the GPS-locations are stored in memory.
      * Time in seconds
@@ -52,16 +54,23 @@ export default class UserRelatedState {
     /**
      * Preferences as tags exposes many preferences and state properties as record.
      * This is used to bridge the internal state with the usersettings.json layerconfig file
+     *
+     * Some metainformation that should not be edited starts with a single underscore
+     * Constants and query parameters start with two underscores
+     * Note: these are linked via OsmConnection.preferences which exports all preferences as UIEventSource
      */
     public readonly preferencesAsTags: UIEventSource<Record<string, string>>
+    private readonly _mapProperties: MapProperties;
 
     constructor(
         osmConnection: OsmConnection,
         availableLanguages?: string[],
         layout?: LayoutConfig,
-        featureSwitches?: FeatureSwitchState
+        featureSwitches?: FeatureSwitchState,
+        mapProperties?: MapProperties
     ) {
         this.osmConnection = osmConnection
+        this._mapProperties = mapProperties;
         {
             const translationMode: UIEventSource<undefined | "true" | "false" | "mobile" | string> =
                 this.osmConnection.GetPreference("translation-mode", "false")
@@ -90,10 +99,13 @@ export default class UserRelatedState {
         )
         this.language = this.osmConnection.GetPreference("language")
         this.showTags = <UIEventSource<any>>this.osmConnection.GetPreference("show_tags")
-        this.fixateNorth = <any>this.osmConnection.GetPreference("fixate-north")
+        this.fixateNorth = <UIEventSource<"yes">>this.osmConnection.GetPreference("fixate-north")
         this.mangroveIdentity = new MangroveIdentity(
             this.osmConnection.GetLongPreference("identity", "mangrove")
         )
+        this.preferredBackgroundLayer= this.osmConnection.GetPreference("preferred-background-layer", undefined, {
+            documentation: "The ID of a layer or layer category that MapComplete uses by default"
+        })
 
         this.installedUserThemes = this.InitInstalledUserThemes()
 
@@ -260,6 +272,7 @@ export default class UserRelatedState {
             amendedPrefs.data["__url_parameter_initialized:" + key] = "yes"
         }
 
+
         const osmConnection = this.osmConnection
         osmConnection.preferencesHandler.preferences.addCallback((newPrefs) => {
             for (const k in newPrefs) {
@@ -280,7 +293,6 @@ export default class UserRelatedState {
             amendedPrefs.ping()
             console.log("Amended prefs are:", amendedPrefs.data)
         })
-        const usersettingsConfig = UserRelatedState.usersettingsConfig
         const translationMode = osmConnection.GetPreference("translation-mode")
 
         Locale.language.mapD(
@@ -335,25 +347,6 @@ export default class UserRelatedState {
             }
 
             usersettingMetaTagging.metaTaggging_for_usersettings({ properties: amendedPrefs.data })
-            /*for (const [name, code, _] of usersettingsConfig.calculatedTags) {
-                try {
-                    let result = new Function("feat", "return " + code + ";")({
-                        properties: amendedPrefs.data,
-                    })
-                    if (result !== undefined && result !== "" && result !== null) {
-                        if (typeof result !== "string") {
-                            result = JSON.stringify(result)
-                        }
-                        amendedPrefs.data[name] = result
-                    }
-                } catch (e) {
-                    console.error(
-                        "Calculating a tag for userprofile-settings failed for variable",
-                        name,
-                        e
-                    )
-                }
-            }*/
 
             const simplifiedName = userDetails.name.toLowerCase().replace(/\s+/g, "")
             const isTranslator = translators.contributors.find(
@@ -407,6 +400,13 @@ export default class UserRelatedState {
             }
         }
 
+
+        this._mapProperties?.rasterLayer?.addCallbackAndRun(l => {
+            amendedPrefs.data["__current_background"] = l?.properties?.id
+            amendedPrefs.ping()
+        })
+
+
         return amendedPrefs
     }
 }