import { ActionReducer, StateAction } from "../StateManager.js";
import { Action } from "../action/DataUnitAction.js";
import StateManager from "../StateManager.js";

class RemovedRecordsReducerImpl implements ActionReducer{
    
    public sliceName: string = "hist::removedRecords";

    public reduce(_stateManager:StateManager, currentState: Array<string>, action: StateAction): Array<string>|undefined {
        switch(action.type){
            case Action.RECORDS_REMOVED:
                const {records, buffered} = action.payload;
                if(buffered){
                    return (currentState||[]).concat(records);
                }
                return currentState;
            case Action.EDITION_CANCELED:
            case Action.DATA_SAVED:
                return undefined;
        }
        return currentState;
    }
}

export const RemovedRecordsReducer = new RemovedRecordsReducerImpl();

export const getRemovedRecords = (stateManager: StateManager): Array<string> => {
    return stateManager.select(RemovedRecordsReducer.sliceName, (state: Array<string>) => state);
};