session-ios/SessionMessagingKit/Database/Models/GroupMember.swift

// Copyright © 2022 Rangeproof Pty Ltd. All rights reserved.

import Foundation
import GRDB
import SessionUtilitiesKit

public struct GroupMember: Codable, Equatable, FetchableRecord, PersistableRecord, TableRecord, ColumnExpressible {
    public static var databaseTableName: String { "groupMember" }
    internal static let openGroupForeignKey = ForeignKey([Columns.groupId], to: [OpenGroup.Columns.threadId])
    internal static let closedGroupForeignKey = ForeignKey([Columns.groupId], to: [ClosedGroup.Columns.threadId])
    public static let openGroup = belongsTo(OpenGroup.self, using: openGroupForeignKey)
    public static let closedGroup = belongsTo(ClosedGroup.self, using: closedGroupForeignKey)
    public static let profile = hasOne(Profile.self, using: Profile.groupMemberForeignKey)
    
    public typealias Columns = CodingKeys
    public enum CodingKeys: String, CodingKey, ColumnExpression {
        case groupId
        case profileId
        case role
    }
    
    public enum Role: Int, Codable, DatabaseValueConvertible {
        case standard
        case zombie
        case moderator
        case admin
    }

    public let groupId: String
    public let profileId: String
    public let role: Role
    
    // MARK: - Relationships
    
    public var openGroup: QueryInterfaceRequest<OpenGroup> {
        request(for: GroupMember.openGroup)
    }
    
    public var closedGroup: QueryInterfaceRequest<ClosedGroup> {
        request(for: GroupMember.closedGroup)
    }
    
    public var profile: QueryInterfaceRequest<Profile> {
        request(for: GroupMember.profile)
    }
    
    // MARK: - Initialization
    
    public init(
        groupId: String,
        profileId: String,
        role: Role
    ) {
        self.groupId = groupId
        self.profileId = profileId
        self.role = role
    }
}

// MARK: - Objective-C Support

// FIXME: Remove when possible

@objc(SMKGroupMember)
public class SMKGroupMember: NSObject {
    @objc(isCurrentUserMemberOf:)
    public static func isCurrentUserMember(of groupId: String) -> Bool {
        return Storage.shared.read { db in
            let userPublicKey: String = getUserHexEncodedPublicKey(db)
            let numEntries: Int = try GroupMember
                .filter(GroupMember.Columns.groupId == groupId)
                .filter(GroupMember.Columns.profileId == userPublicKey)
                .fetchCount(db)
            
            return (numEntries > 0)
        }
        .defaulting(to: false)
    }
    
    @objc(isCurrentUserAdminOf:)
    public static func isCurrentUserAdmin(of groupId: String) -> Bool {
        return Storage.shared.read { db in
            let userPublicKey: String = getUserHexEncodedPublicKey(db)
            let numEntries: Int = try GroupMember
                .filter(GroupMember.Columns.groupId == groupId)
                .filter(GroupMember.Columns.profileId == userPublicKey)
                .filter(GroupMember.Columns.role == GroupMember.Role.admin)
                .fetchCount(db)
            
            return (numEntries > 0)
        }
        .defaulting(to: false)
    }
}