fix(platform-add): respect nativePlatformStatus property from .nsprepare file when adding the platform

As the preview command add only the .js part of the platform, we need to check nativePlatformStatus in order to decide correctly if platform add is necessary

Author: Fatme

lib/services/platform-service.ts

@@ -69,14 +69,28 @@ export class PlatformService extends EventEmitter implements IPlatformService {
 			this.validatePlatform(platform, projectData);
 			const platformPath = path.join(projectData.platformsDir, platform);
 
-			if (this.$fs.exists(platformPath)) {
+			const isPlatformAdded = this.isPlatformAdded(platform, platformPath, projectData);
+			if (isPlatformAdded) {
 				this.$errors.failWithoutHelp(`Platform ${platform} already added`);
 			}
 
 			await this.addPlatform(platform.toLowerCase(), platformTemplate, projectData, config, frameworkPath);
 		}
 	}
 
+	private isPlatformAdded(platform: string, platformPath: string, projectData: IProjectData): boolean {
+		if (!this.$fs.exists(platformPath)) {
+			return false;
+		}
+
+		const prepareInfo = this.$projectChangesService.getPrepareInfo(platform, projectData);
+		if (!prepareInfo) {
+			return true;
+		}
+
+		return prepareInfo.nativePlatformStatus !== constants.NativePlatformStatus.requiresPlatformAdd;
+	}
+
 	public getCurrentPlatformVersion(platform: string, projectData: IProjectData): string {
 		const platformData = this.$platformsData.getPlatformData(platform, projectData);
 		const currentPlatformData: any = this.$projectDataService.getNSValue(projectData.projectDir, platformData.frameworkPackageName);