import { EVirtualState } from './state-machine';
import { LogAndError } from "@birbal/common-utilities/dist/error";

export class VirtualStatusCheck {
    static async checkForStatusChange(to: EVirtualState, from?: EVirtualState) {
        switch (to) {
            case EVirtualState.PENDING:
                if (!from) return;    
                throw new LogAndError("State change not allowed: From " + from + " to " + to);

            case EVirtualState.SUBMITTED:
                if (from === EVirtualState.PENDING) return;
                throw new LogAndError("State change not allowed: From " + from + " to " + to);

            case EVirtualState.REJECTED:
                if (from === EVirtualState.SUBMITTED) return;
                throw new LogAndError("State change not allowed: From " + from + " to " + to);

            case EVirtualState.REMOVED:
                if (from === EVirtualState.SUBMITTED) return;
                throw new LogAndError("State change not allowed: From " + from + " to " + to);

            case EVirtualState.APPROVED:
                if (from === EVirtualState.SUBMITTED || from === EVirtualState.REVOKED
                     || from === EVirtualState.EXPIRED) return;
                throw new LogAndError("State change not allowed: From " + from + " to " + to);

            case EVirtualState.EXPIRED:
                if (from === EVirtualState.APPROVED) return;
                throw new LogAndError("State change not allowed: From " + from + " to " + to);

            case EVirtualState.REVOKED:
                if (from === EVirtualState.APPROVED) return;
                throw new LogAndError("State change not allowed: From " + from + " to " + to);

            default:
            throw new LogAndError("Invalid state request");
        }
    }

}