import { RequestHandler } from "../entities/RequestHandler";
import { GroupsHelper } from "../helpers/GroupsHelper";
import { GroupsAccessLevel, GroupInfo, GroupVisibilityLevel, GroupPostsCreationLevel, GroupRegistrationLevel } from "../entities/Group";
import { GroupMembershipLevels } from "../entities/GroupMember";
import { time } from "../utils/DateUtils";

/**
 * Groups API controller
 * 
 * @author Pierre HUBERT
 */

/**
 * API groups registration levels
 */
const GROUPS_REGISTRATION_LEVELS = [];
GROUPS_REGISTRATION_LEVELS[GroupRegistrationLevel.OPEN_REGISTRATION] = "open";
GROUPS_REGISTRATION_LEVELS[GroupRegistrationLevel.MODERATED_REGISTRATION] = "moderated";
GROUPS_REGISTRATION_LEVELS[GroupRegistrationLevel.CLOSED_REGISTRATION] = "closed";

/**
 * API groups membership levels
 */
const GROUPS_MEMBERSHIP_LEVELS = [];
GROUPS_MEMBERSHIP_LEVELS[GroupMembershipLevels.ADMINISTRATOR] = "administrator";
GROUPS_MEMBERSHIP_LEVELS[GroupMembershipLevels.MODERATOR] = "moderator";
GROUPS_MEMBERSHIP_LEVELS[GroupMembershipLevels.MEMBER] = "member";
GROUPS_MEMBERSHIP_LEVELS[GroupMembershipLevels.INVITED] = "invited";
GROUPS_MEMBERSHIP_LEVELS[GroupMembershipLevels.PENDING] = "pending";
GROUPS_MEMBERSHIP_LEVELS[GroupMembershipLevels.VISITOR] = "visitor";


/**
 * API groups visibility levels
 */
const GROUPS_VISIBILITY_LEVELS = [];
GROUPS_VISIBILITY_LEVELS[GroupVisibilityLevel.OPEN_GROUP] = "open";
GROUPS_VISIBILITY_LEVELS[GroupVisibilityLevel.PRIVATE_GROUP] = "private";
GROUPS_VISIBILITY_LEVELS[GroupVisibilityLevel.SECRETE_GROUP] = "secrete";


/**
 * API posts creation levels
 */
const GROUPS_POSTS_LEVELS = [];
GROUPS_POSTS_LEVELS[GroupPostsCreationLevel.POSTS_LEVEL_MODERATORS] = "moderators";
GROUPS_POSTS_LEVELS[GroupPostsCreationLevel.POSTS_LEVEL_ALL_MEMBERS] = "members";


export class GroupsController {

	/**
	 * Create a new group
	 * 
	 * @param h Request handler
	 */
	public static async Create(h: RequestHandler) {
		const name = h.postString("name", 3);

		const groupID = await GroupsHelper.Create({
			name: name,
			userID: h.getUserId(),
			timeCreate: time()
		});

		h.send({
			success: "The group has been successfully created!",
			id: groupID
		});
	}

	/**
	 * Get the list of groups of the user
	 * 
	 * @param h Request handler
	 */
	public static async GetListUser(h: RequestHandler) {
		h.send(await GroupsHelper.GetListUser(h.getUserId()));
	}

	/**
	 * Get information about a single group
	 * 
	 * @param h Request handler
	 */
	public static async GetInfoSingle(h: RequestHandler) {
		const groupID = await h.postGroupIDWithAccess("id", GroupsAccessLevel.LIMITED_ACCESS);
		const groupInfo = await GroupsHelper.GetInfo(groupID);
		
		h.send(await this.GroupInfoToAPI(groupInfo, h));
	}

	/**
	 * Get information about multiple users
	 * 
	 * @param h Request handler
	 */
	public static async GetInfoMultiple(h: RequestHandler) {
		const ids = h.postNumbersList("list");

		const result = {};

		for (const id of ids) {
			
			// Check group existence & user authorization
			if(!await GroupsHelper.Exists(id)
				|| await GroupsHelper.GetAccessLevel(id, h.getUserId()) < GroupsAccessLevel.LIMITED_ACCESS)
				h.error(404, "Group " + id + " not found");

			const group = await GroupsHelper.GetInfo(id);

			result[id] = await this.GroupInfoToAPI(group, h);
		}

		h.send(result);
	}

	/**
	 * Get advanced information about a group
	 * 
	 * @param h Request handler
	 */
	public static async GetAdvancedInfo(h: RequestHandler) {
		const groupID = await h.postGroupIDWithAccess("id", GroupsAccessLevel.VIEW_ACCESS);

		const group = await GroupsHelper.GetInfo(groupID);

		h.send(await this.GroupInfoToAPI(group, h));
	}

	/**
	 * Turn a GroupInfo object into a valid API object
	 * 
	 * @param info Information about the group
	 * @returns Generated object
	 */
	private static async GroupInfoToAPI(info: GroupInfo, h: RequestHandler) : Promise<any> {
		
		const membership = await GroupsHelper.GetMembershipInfo(info.id, h.getUserId())
		
		return {
			id: info.id,
			name: info.name,
			icon_url: info.logoURL,
			number_members: info.membersCount,
			visibility: GROUPS_VISIBILITY_LEVELS[info.visiblity],
			registration_level: GROUPS_REGISTRATION_LEVELS[info.registrationLevel],
			posts_level: GROUPS_POSTS_LEVELS[info.postsCreationLevel],
			virtual_directory: info.virtualDirectory ? info.virtualDirectory : "null",

			membership: GROUPS_MEMBERSHIP_LEVELS[membership ? membership.level : GroupMembershipLevels.VISITOR],
			following: membership ? membership.following : false
		}
	}
}