import {SessionModel} from './SessionModel'
import {Container} from '../../di'
import {NoSessionKeyError, Session, SessionData, SessionNotLoadedError} from '../../http/session/Session'

/**
 * An implementation of the Session driver whose records are stored in a database table.
 */
export class ORMSession extends Session {
    protected key?: string

    protected data?: SessionData

    protected session?: SessionModel

    public getKey(): string {
        if ( !this.key ) {
            throw new NoSessionKeyError()
        }

        return this.key
    }

    public setKey(key: string): void {
        this.key = key
    }

    public async load(): Promise<void> {
        if ( !this.key ) {
            throw new NoSessionKeyError()
        }

        const session = <SessionModel> await SessionModel.findByKey(this.key)
        if ( session ) {
            this.session = session
            this.data = this.session.json
        } else {
            this.session = <SessionModel> Container.getContainer().make(SessionModel)
            this.session.sessionUuid = this.key
            this.data = {} as SessionData
        }
    }

    public async persist(): Promise<void> {
        if ( !this.key ) {
            throw new NoSessionKeyError()
        }
        if ( !this.data || !this.session ) {
            throw new SessionNotLoadedError()
        }

        this.session.sessionUuid = this.key
        this.session.json = JSON.stringify(this.data)
        await this.session.save()
    }

    public getData(): SessionData {
        if ( !this.data ) {
            throw new SessionNotLoadedError()
        }
        return this.data
    }

    public setData(data: SessionData): void {
        this.data = data
    }

    public get(key: string, fallback?: unknown): any {
        if ( !this.data ) {
            throw new SessionNotLoadedError()
        }

        return this.data[key] ?? fallback
    }

    public set(key: string, value: unknown): void {
        if ( !this.data ) {
            throw new SessionNotLoadedError()
        }

        this.data[key] = value
    }

    public forget(key: string): void {
        if ( !this.data ) {
            throw new SessionNotLoadedError()
        }

        delete this.data[key]
    }
}