import {Injectable, Inject} from "@extollo/di"
import {ErrorWithContext} from "@extollo/util"
import {Request} from "../lifecycle/Request"

export type SessionData = {[key: string]: any}

export class NoSessionKeyError extends ErrorWithContext {
    constructor() {
        super('No session ID has been set.')
    }
}

export class SessionNotLoadedError extends ErrorWithContext {
    constructor() {
        super('Cannot access session data; data is not loaded.')
    }
}

@Injectable()
export abstract class Session {
    @Inject()
    protected readonly request!: Request

    public abstract getKey(): string

    public abstract setKey(key: string): void

    public abstract load(): void | Promise<void>

    public abstract persist(): void | Promise<void>

    public abstract getData(): SessionData

    public abstract setData(data: SessionData): void

    public abstract get(key: string, fallback?: any): any

    public abstract set(key: string, value: any): void
}