import Foundation
import Postbox


public enum TelegramChannelPermission {
    case sendText
    case sendPhoto
    case sendVideo
    case sendSomething
    case pinMessages
    case manageTopics
    case createTopics
    case inviteMembers
    case editAllMessages
    case deleteAllMessages
    case banMembers
    case addAdmins
    case changeInfo
    case canBeAnonymous
    case manageCalls
    case postStories
    case editStories
    case deleteStories
}

public extension TelegramChannel {
    func hasPermission(_ permission: TelegramChannelPermission, ignoreDefault: Bool = false) -> Bool {
        if self.flags.contains(.isCreator) {
            if case .canBeAnonymous = permission {
                if let adminRights = self.adminRights {
                    return adminRights.rights.contains(.canBeAnonymous)
                } else {
                    return false
                }
            }
            return true
        }
        switch permission {
            case .sendText:
                if case .broadcast = self.info {
                    if let adminRights = self.adminRights {
                        return adminRights.rights.contains(.canPostMessages)
                    } else {
                        return false
                    }
                } else {
                    if let _ = self.adminRights {
                        return true
                    }
                    if let bannedRights = self.bannedRights, bannedRights.flags.contains(.banSendText) {
                        return false
                    }
                    if let defaultBannedRights = self.defaultBannedRights, defaultBannedRights.flags.contains(.banSendText) && !ignoreDefault {
                        return false
                    }
                    return true
                }
            case .sendPhoto:
                if case .broadcast = self.info {
                    if let adminRights = self.adminRights {
                        return adminRights.rights.contains(.canPostMessages)
                    } else {
                        return false
                    }
                } else {
                    if let _ = self.adminRights {
                        return true
                    }
                    if let bannedRights = self.bannedRights, bannedRights.flags.contains(.banSendPhotos) {
                        return false
                    }
                    if let defaultBannedRights = self.defaultBannedRights, defaultBannedRights.flags.contains(.banSendPhotos) && !ignoreDefault {
                        return false
                    }
                    return true
                }
            case .sendVideo:
                if case .broadcast = self.info {
                    if let adminRights = self.adminRights {
                        return adminRights.rights.contains(.canPostMessages)
                    } else {
                        return false
                    }
                } else {
                    if let _ = self.adminRights {
                        return true
                    }
                    if let bannedRights = self.bannedRights, bannedRights.flags.contains(.banSendVideos) {
                        return false
                    }
                    if let defaultBannedRights = self.defaultBannedRights, defaultBannedRights.flags.contains(.banSendVideos) && !ignoreDefault {
                        return false
                    }
                    return true
                }
            case .sendSomething:
                if case .broadcast = self.info {
                    if let adminRights = self.adminRights {
                        return adminRights.rights.contains(.canPostMessages)
                    } else {
                        return false
                    }
                } else {
                    if let _ = self.adminRights {
                        return true
                    }
                    
                    let flags: TelegramChatBannedRightsFlags = [
                        .banSendText,
                        .banSendInstantVideos,
                        .banSendVoice,
                        .banSendPhotos,
                        .banSendVideos,
                        .banSendStickers,
                        .banSendPolls,
                        .banSendFiles,
                        .banSendInline,
                        .banSendMusic
                    ]
                    
                    if let bannedRights = self.bannedRights, bannedRights.flags.intersection(flags) == flags {
                        return false
                    }
                    if let defaultBannedRights = self.defaultBannedRights, defaultBannedRights.flags.intersection(flags) == flags && !ignoreDefault {
                        return false
                    }
                    return true
                }
            case .pinMessages:
                if case .broadcast = self.info {
                    if let adminRights = self.adminRights {
                        return adminRights.rights.contains(.canPinMessages) || adminRights.rights.contains(.canEditMessages)
                    } else {
                        return false
                    }
                } else {
                    if let adminRights = self.adminRights, adminRights.rights.contains(.canPinMessages) {
                        return true
                    }
                    if let bannedRights = self.bannedRights, bannedRights.flags.contains(.banPinMessages) {
                        return false
                    }
                    if let defaultBannedRights = self.defaultBannedRights, defaultBannedRights.flags.contains(.banPinMessages) {
                        return false
                    }
                    return true
                }
            case .manageTopics:
                if self.flags.contains(.isCreator) {
                    return true
                }
                if self.adminRights == nil {
                    return false
                }
                if let adminRights = self.adminRights, adminRights.rights.contains(.canManageTopics) {
                    return true
                }
                return false
            case .createTopics:
                if self.flags.contains(.isCreator) {
                    return true
                }
                if let adminRights = self.adminRights, adminRights.rights.contains(.canManageTopics) {
                    return true
                }
                if let bannedRights = self.bannedRights, bannedRights.flags.contains(.banManageTopics) {
                    return false
                }
                if let defaultBannedRights = self.defaultBannedRights, defaultBannedRights.flags.contains(.banManageTopics) {
                    return false
                }
                return true
            case .inviteMembers:
                if case .broadcast = self.info {
                    if let adminRights = self.adminRights {
                        return adminRights.rights.contains(.canInviteUsers)
                    } else {
                        return false
                    }
                } else {
                    if let adminRights = self.adminRights, adminRights.rights.contains(.canInviteUsers) {
                        return true
                    }
                    if let bannedRights = self.bannedRights, bannedRights.flags.contains(.banAddMembers) {
                        return false
                    }
                    if let defaultBannedRights = self.defaultBannedRights, defaultBannedRights.flags.contains(.banAddMembers) {
                        return false
                    }
                    return true
                }
            case .editAllMessages:
                if let adminRights = self.adminRights, adminRights.rights.contains(.canEditMessages) {
                    return true
                }
                return false
            case .deleteAllMessages:
                if let adminRights = self.adminRights, adminRights.rights.contains(.canDeleteMessages) {
                    return true
                }
                return false
            case .banMembers:
                if let adminRights = self.adminRights, adminRights.rights.contains(.canBanUsers) {
                    return true
                }
                return false
            case .changeInfo:
                if case .broadcast = self.info {
                    if let adminRights = self.adminRights {
                        return adminRights.rights.contains(.canChangeInfo)
                    } else {
                        return false
                    }
                } else {
                    if let adminRights = self.adminRights, adminRights.rights.contains(.canChangeInfo) {
                        return true
                    }
                    if let bannedRights = self.bannedRights, bannedRights.flags.contains(.banChangeInfo) {
                        return false
                    }
                    if let defaultBannedRights = self.defaultBannedRights, defaultBannedRights.flags.contains(.banChangeInfo) {
                        return false
                    }
                    return true
                }
            case .addAdmins:
                if let adminRights = self.adminRights, adminRights.rights.contains(.canAddAdmins) {
                    return true
                }
                return false
            case .manageCalls:
                if let adminRights = self.adminRights, adminRights.rights.contains(.canManageCalls) {
                    return true
                }
                return false
            case .canBeAnonymous:
                if let adminRights = self.adminRights, adminRights.rights.contains(.canBeAnonymous) {
                    return true
                }
                return false
            case .postStories:
                if let adminRights = self.adminRights {
                    return adminRights.rights.contains(.canPostStories)
                } else {
                    return false
                }
            case .editStories:
                if let adminRights = self.adminRights {
                    return adminRights.rights.contains(.canEditStories)
                } else {
                    return false
                }
            case .deleteStories:
                if let adminRights = self.adminRights {
                    return adminRights.rights.contains(.canDeleteStories)
                } else {
                    return false
                }
        }
    }
    
    func hasBannedPermission(_ rights: TelegramChatBannedRightsFlags, ignoreDefault: Bool = false) -> (Int32, Bool)? {
        if self.flags.contains(.isCreator) {
            return nil
        }
        if let _ = self.adminRights {
            return nil
        }
        if let defaultBannedRights = self.defaultBannedRights, defaultBannedRights.flags.contains(rights) && !ignoreDefault {
            return (Int32.max, false)
        }
        if let bannedRights = self.bannedRights, bannedRights.flags.contains(rights) {
            return (bannedRights.untilDate, true)
        }
        return nil
    }
    
    var isRestrictedBySlowmode: Bool {
        if self.flags.contains(.isCreator) {
            return false
        }
        if let _ = self.adminRights {
            return false
        }
        if case let .group(group) = self.info {
            return group.flags.contains(.slowModeEnabled)
        } else {
            return false
        }
    }
}