function log_ts(message) {
    console.log(new Date().toISOString() + " " + message);
}


async function checkDates() {
    log_ts('checkDates start');
    config.countdown = config.frequency * minute;
    await chrome.storage.local.set({ "__countdown": config.countdown });
    log_ts('checkDates done');
}

async function runner() {
    // log_ts('runner start');
    let prev_config = Object.assign({}, config);

    let result = await new Promise(resolve => chrome.storage.local.get(null, resolve));
    config.activate = result['__activate'] || false;
    config.username = result['__username'] || "";
    config.password = result['__password'] || "";
    config.frequency = result['__frequency'] || 1;
    config.countdown = result['__countdown'] || 0;

    if (prev_config.activate === null) {
        log_ts('Reading config: ' + JSON.stringify(config));
        return;
    }

    let configChanged = false;
    for (let key in config) {
        if (config.hasOwnProperty(key) && config[key] !== prev_config[key]) {
            log_ts(`Config change: ${key}, ${prev_config[key]} => ${config[key]}`);
            configChanged = true;
            // reduce countdown if frequency is reduced
            if (key === 'frequency') {
                let max_countdown = config[key] * minute;
                if (config.countdown > max_countdown) {
                    config.countdown = max_countdown;
                    await chrome.storage.local.set({ "__countdown": config.countdown });
                }
            }
        }
    }
    if (configChanged) {
        // print whole config
        log_ts(JSON.stringify(config));
    }

    if (config.activate && !prev_config.activate) {
        log_ts('Activating extension');
        config.countdown = 5;
    }

    if (!config.activate) {
        // reset countdown when deactivating the extension
        if (prev_config.activate) {
            log_ts('Deactivating extension');
            config.countdown = 0;
            await chrome.storage.local.set({ "__countdown": config.countdown });
        }
        return;
    }

    if (config.username === "" || config.password === "") {
        log_ts('Username or password is empty');
        return;
    }

    if (config.frequency <= 0) {
        log_ts('Frequency is 0');
        return;
    }

    if (config.countdown > 0) {
        config.countdown -= 1;
        log_ts(`Countdown: ${config.countdown}`);
        await chrome.storage.local.set({ "__countdown": config.countdown });
        return;
    }

    checkDates();

    
    // log_ts('runner done');
}

let config = {
    activate: null,
    username: null,
    password: null,
    frequency: null,
    countdown: null,
};
let minute = 60;

setInterval(runner, 1000);