// Copyright © 2023 Rangeproof Pty Ltd. All rights reserved.

import Foundation
import Combine
import GRDB
import SessionUtilitiesKit
import SessionSnodeKit

public enum GroupInviteMemberJob: JobExecutor {
    public static var maxFailureCount: Int = 1
    public static var requiresThreadId: Bool = true
    public static var requiresInteractionId: Bool = false
    
    public static func run(
        _ job: Job,
        queue: DispatchQueue,
        success: @escaping (Job, Bool, Dependencies) -> (),
        failure: @escaping (Job, Error?, Bool, Dependencies) -> (),
        deferred: @escaping (Job, Dependencies) -> (),
        using dependencies: Dependencies
    ) {
        guard
            let threadId: String = job.threadId,
            let detailsData: Data = job.details,
            let currentInfo: (groupName: String, adminProfile: Profile) = dependencies[singleton: .storage].read({ db in
                let maybeGroupName: String? = try ClosedGroup
                    .filter(id: threadId)
                    .select(.name)
                    .asRequest(of: String.self)
                    .fetchOne(db)
                
                guard let groupName: String = maybeGroupName else { throw StorageError.objectNotFound }
                
                return (groupName, Profile.fetchOrCreateCurrentUser(db, using: dependencies))
            }),
            let details: Details = try? JSONDecoder(using: dependencies).decode(Details.self, from: detailsData)
        else {
            SNLog("[GroupInviteMemberJob] Failing due to missing details")
            failure(job, JobRunnerError.missingRequiredDetails, true, dependencies)
            return
        }
        
        let sentTimestamp: Int64 = SnodeAPI.currentOffsetTimestampMs(using: dependencies)
        
        /// Perform the actual message sending
        dependencies[singleton: .storage]
            .readPublisher { db -> HTTP.PreparedRequest<Void> in
                try MessageSender.preparedSend(
                    db,
                    message: try GroupUpdateInviteMessage(
                        inviteeSessionIdHexString: details.memberSessionIdHexString,
                        groupSessionId: SessionId(.group, hex: threadId),
                        groupName: currentInfo.groupName,
                        memberAuthData: details.memberAuthData,
                        profile: VisibleMessage.VMProfile.init(
                            profile: currentInfo.adminProfile,
                            blocksCommunityMessageRequests: nil
                        ),
                        sentTimestamp: UInt64(sentTimestamp),
                        authMethod: try Authentication.with(
                            db,
                            sessionIdHexString: threadId,
                            using: dependencies
                        ),
                        using: dependencies
                    ),
                    to: .contact(publicKey: details.memberSessionIdHexString),
                    namespace: .default,
                    interactionId: nil,
                    fileIds: [],
                    isSyncMessage: false,
                    using: dependencies
                )
            }
            .flatMap { $0.send(using: dependencies) }
            .subscribe(on: queue, using: dependencies)
            .receive(on: queue, using: dependencies)
            .sinkUntilComplete(
                receiveCompletion: { result in
                    switch result {
                        case .finished: success(job, false, dependencies)
                        case .failure(let error):
                            SNLog("[GroupInviteMemberJob] Couldn't send message due to error: \(error).")
                            
                            // Update the invite status of the group member (only if the role is 'standard' and
                            // the role status isn't already 'accepted')
                            dependencies[singleton: .storage].write(using: dependencies) { db in
                                try GroupMember
                                    .filter(
                                        GroupMember.Columns.groupId == threadId &&
                                        GroupMember.Columns.profileId == details.memberSessionIdHexString &&
                                        GroupMember.Columns.role == GroupMember.Role.standard &&
                                        GroupMember.Columns.roleStatus != GroupMember.RoleStatus.accepted
                                    )
                                    .updateAllAndConfig(
                                        db,
                                        GroupMember.Columns.roleStatus.set(to: GroupMember.RoleStatus.failed),
                                        using: dependencies
                                    )
                            }
                            
                            // Register the failure
                            switch error {
                                case let senderError as MessageSenderError where !senderError.isRetryable:
                                    failure(job, error, true, dependencies)
                                    
                                case OnionRequestAPIError.httpRequestFailedAtDestination(let statusCode, _, _) where statusCode == 429: // Rate limited
                                    failure(job, error, true, dependencies)
                                    
                                case SnodeAPIError.clockOutOfSync:
                                    SNLog("[GroupInviteMemberJob] Permanently Failing to send due to clock out of sync issue.")
                                    failure(job, error, true, dependencies)
                                    
                                default: failure(job, error, false, dependencies)
                            }
                    }
                }
            )
        
        // TODO: Need to batch errors together and send a toast indicating invitation failures
    }
}

// MARK: - GroupInviteMemberJob.Details

extension GroupInviteMemberJob {
    public struct Details: Codable {
        public let memberSessionIdHexString: String
        public let memberAuthData: Data
        
        public init(
            memberSessionIdHexString: String,
            authInfo: Authentication.Info
        ) throws {
            self.memberSessionIdHexString = memberSessionIdHexString
            
            switch authInfo {
                case .groupMember(_, let authData): self.memberAuthData = authData
                default: throw MessageSenderError.invalidMessage
            }
        }
    }
}