Start implementation of post system

src/helpers/PostsHelper.ts

@@ -0,0 +1,162 @@
+import { PostKind, PostVisibilityLevel, Post, PostPageKind, PostFile, PostLink } from "../entities/Post";
+import { FriendsHelper } from "./FriendsHelper";
+import { DatabaseHelper } from "./DatabaseHelper";
+
+/**
+ * Posts helper
+ * 
+ * @author Pierre HUBERT
+ */
+
+/**
+ * Table name
+ */
+const TABLE_NAME = "texte";
+
+/**
+ * Database mapping
+ */
+const PostDBTypes : Record<string, PostKind> = {
+	"texte": PostKind.POST_KIND_IMAGE,
+	"image": PostKind.POST_KIND_IMAGE,
+	"webpage_link": PostKind.POST_KIND_WEBLINK,
+	"pdf": PostKind.POST_KIND_PDF,
+	"video": PostKind.POST_KIND_MOVIE,
+	"count_down": PostKind.POST_KIND_COUNTDOWN,
+	"sondage": PostKind.POST_KIND_SURVEY,
+	"youtube": PostKind.POST_KIND_YOUTUBE
+}
+
+/**
+ * Posts helper
+ */
+export class PostsHelper {
+
+	/**
+	 * Get the posts of a user
+	 * 
+	 * @param userID The ID of the user making the request
+	 * @param targetID The ID of the target user
+	 * @param startFrom Start point (0 = none)
+	 * @param limit Maximum number of messages to fetch
+	 */
+	public static async GetUserPosts(userID: number, targetID: number, 
+		startFrom: number = 0, limit: number = 10) : Promise<Array<Post>> {
+		
+		if(limit < 1) 
+			throw Error("Limit of post query must be greater or equal to one!");
+
+		
+		// Determine max user visibility
+		let level : PostVisibilityLevel = PostVisibilityLevel.VISIBILITY_PUBLIC;
+
+		if(userID == targetID)
+			level = PostVisibilityLevel.VISIBILITY_USER;
+		
+		else if(userID > 0 && await FriendsHelper.AreFriend(userID, targetID))
+			level = PostVisibilityLevel.VISIBILITY_FRIENDS;
+		
+		
+
+		// Preprocess conditions
+		
+		/// ============= PERMISSION CONDITIONS =================
+		// Visibility level
+		let customWhere = "((niveau_visibilite <= ?) ";
+		let customWhereArgs =  [level.toString()];
+
+		// Add user post (if user signed in)
+		if(userID > 0) {
+			customWhere += " OR (ID_amis = ?) ";
+			customWhereArgs.push(userID.toString());
+		}
+
+		customWhere += ")"
+		/// ============= /PERMISSION CONDITIONS ================
+
+
+
+		// ============== START POINT CONDITION =================
+		if(startFrom != 0) {
+			customWhere += " AND ID <= ?";
+			customWhereArgs.push(startFrom.toString());
+		}
+		// ============== /START POINT CONDITION ================
+
+
+
+		// Perform the request
+		const entries = await DatabaseHelper.Query({
+			table: TABLE_NAME,
+			
+			// Base conditions
+			where: {
+				ID_personne: targetID,
+				group_id: 0
+			},
+
+			customWhere: customWhere,
+			customWhereArgs: customWhereArgs,
+
+			order: "ID DESC",
+			limit: limit,
+		});
+
+		return entries.map((r) => this.DBToPost(r));
+	}
+
+	/**
+	 * Turn a database entry into a row object
+	 * 
+	 * @param row The database entry
+	 */
+	private static DBToPost(row: any) : Post {
+
+		const postPageKind = row.group_id == 0 ? PostPageKind.PAGE_KIND_USER : PostPageKind.PAGE_KIND_GROUP;
+
+		const postType = PostDBTypes[row.type];
+
+		return new Post({
+			// General info
+			id: row.ID,
+			userID: row.ID_amis == 0 ? row.ID_personne : row.ID_amis,
+
+
+			// Kind of target of the page and its ID
+			kindPage: postPageKind,
+			pageID: postPageKind == PostPageKind.PAGE_KIND_USER ? row.ID_personne : row.group_id,
+
+			// Basic info
+			timeCreate: row.time_insert == null ? (new Date(row.date_envoi).getTime() / 1000) : row.time_insert,
+			content: row.texte,
+			visibilityLevel: row.niveau_visibilite,
+			kind: postType,
+
+			// Files specific
+			file: row.path == null ? undefined : new PostFile({
+				size: Number(row.size),
+				type: row.file_type,
+				path: row.path
+			}),
+
+			// Movies specific
+			movieID: row.idvideo == null ? undefined : row.idvideo,
+
+			// Coutdown timer specific
+			timeEnd: (row.time_end && row.time_end) > 0 ? row.time_end
+
+				// Coutdown legacy support
+				: (row.annee_fin && row.annee_fin > 2010 ? new Date(row.annee_fin + "/" + row.mois_fin + "/" + row.jour_fin).getTime() / 1000 : undefined),
+
+			
+			// Weblink - specific
+			link: row.url_page == null ? undefined :
+				new PostLink({
+					url: row.url_page,
+					title: row.titre_page,
+					description: row.description_page,
+					image: row.image_page
+				}), 
+		});
+	}
+}