Feature/graphql web UI (#649)

* Add "server" to "checkForUpdate" logic names

* Use "webUIRoot" as default path for "getLocalVersion"

* Use local version as default version for "isUpdateAvailable"

* Return the version with the webUI update check

* Update WebinterfaceManager to be async

* Add query, mutation and subscription for webUI update

* Catch error and return default error value for missing local WebUI version

server/src/main/kotlin/suwayomi/tachidesk/graphql/mutations/InfoMutation.kt

@@ -0,0 +1,62 @@
+package suwayomi.tachidesk.graphql.mutations
+
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.withTimeout
+import suwayomi.tachidesk.graphql.types.UpdateState.DOWNLOADING
+import suwayomi.tachidesk.graphql.types.UpdateState.FINISHED
+import suwayomi.tachidesk.graphql.types.UpdateState.STOPPED
+import suwayomi.tachidesk.graphql.types.WebUIUpdateInfo
+import suwayomi.tachidesk.graphql.types.WebUIUpdateStatus
+import suwayomi.tachidesk.server.JavalinSetup.future
+import suwayomi.tachidesk.server.serverConfig
+import suwayomi.tachidesk.server.util.WebInterfaceManager
+import java.util.concurrent.CompletableFuture
+import kotlin.time.Duration.Companion.seconds
+
+class InfoMutation {
+    data class WebUIUpdateInput(
+        val clientMutationId: String? = null
+    )
+
+    data class WebUIUpdatePayload(
+        val clientMutationId: String?,
+        val updateStatus: WebUIUpdateStatus
+    )
+
+    fun updateWebUI(input: WebUIUpdateInput): CompletableFuture<WebUIUpdatePayload> {
+        return future {
+            withTimeout(30.seconds) {
+                if (WebInterfaceManager.status.value.state === DOWNLOADING) {
+                    return@withTimeout WebUIUpdatePayload(input.clientMutationId, WebInterfaceManager.status.value)
+                }
+
+                val (version, updateAvailable) = WebInterfaceManager.isUpdateAvailable()
+
+                if (!updateAvailable) {
+                    return@withTimeout WebUIUpdatePayload(
+                        input.clientMutationId,
+                        WebUIUpdateStatus(
+                            info = WebUIUpdateInfo(
+                                channel = serverConfig.webUIChannel,
+                                tag = version,
+                                updateAvailable
+                            ),
+                            state = STOPPED,
+                            progress = 0
+                        )
+                    )
+                }
+                try {
+                    WebInterfaceManager.startDownloadInScope(version)
+                } catch (e: Exception) {
+                    // ignore since we use the status anyway
+                }
+
+                WebUIUpdatePayload(
+                    input.clientMutationId,
+                    updateStatus = WebInterfaceManager.status.first { it.state == DOWNLOADING }
+                )
+            }
+        }
+    }
+}