swimtracker-app/state/Reducer.js

import { combineReducers } from 'redux';
import { CHANGE_THEME, CHANGE_USER_NAME, NEW_DEVICE_DATA, START_SESSION, STOP_SESSION, RESET_DEVICE_DATA } from './ActionCreators';
import { deviceStateReducer } from "./DeviceReduxCoupling";

const INITIAL_SETTINGS = {
    theme: "hot",
    username: "",
    swimTrackerHost: "192.168.178.110",

    analysis: {
        peaksPerLap: 30,
        windowSizeInSecs: 5,
        numMeasurementsPerSec: 10,

        peakDetector: 'SIMPLE', // either 'SIMPLE' or 'ZSCORE'
        peakDetectorSimpleThreshold: 2500,

        peakDetectorZScoreLag: 8, // peak detector z-score values
        peakDetectorZScoreThreshold: 2,
        peakDetectorZScoreInfluence: 0.1,
    }
};


const settingsReducer = (state = INITIAL_SETTINGS, action) => {
    switch (action.type) {
        case CHANGE_THEME:
            return { ...state, theme: action.newThemeName };
        case CHANGE_USER_NAME:
            return { ...state, username: action.newUsername };
        default:
            return state
    }
};

export default combineReducers({
    settings: settingsReducer,
    deviceState: deviceStateReducer,
});