background.js

async function getSensorState(haConn, sensor_name) {
    const response = await fetch(`${haConn?.url}/api/states/input_select.${sensor_name}`, {
        headers: {
            "Authorization": `Bearer ${haConn?.token}`,
            "content-type": "application/json",
        },
    });
    const result = await response.json();
    return result?.state;
}

async function updateSensorState(haConn, sensor_name, friendly_name, websiteState, currentTab) {
    let running = websiteState.button_state ? "Enabled" : "Disabled";
    if (currentTab == undefined) {
        running = "Unavailable"
    }
    const response = await fetch(`${haConn?.url}/api/states/input_select.${sensor_name}`, {
        method: "POST",
        headers: {
            "Authorization": `Bearer ${haConn?.token}`,
            "content-type": "application/json",
        },
        body: JSON.stringify({
            "state": running,
            "attributes": {
                "friendly_name": friendly_name,
                "options": [
                    "Enable",
                    "Disable",
                    "Disabled",
                    "Enabled",
                    "Unavailable"
                ],
                "url": websiteState.direct_link || "",
                "image": websiteState.qr_code || "",
                "editable": false,
                "icon": "mdi:translate",
            },

        })
    });
    if (!response.ok) {
        console.error("Received incorrect response from homeassistant api");
    }
}

chrome.runtime.onInstalled.addListener(() => {
    chrome.alarms.get('periodic', a => {
        if (!a) chrome.alarms.create('periodic', { periodInMinutes: 0.1 });
    });
});

chrome.alarms.onAlarm.addListener(() => {
    chrome.tabs.query({ url: "*://trandelion.com/mytrandelion*" }, async (tabs) => {
        let websiteState = { button_state: false, qr_code: undefined, direct_link: undefined };
        let currentTab = undefined;
        for (const tab of tabs) {
            const response = await chrome.tabs.sendMessage(tab.id, { action: "check" });
            if (![null, undefined].includes(response?.button_state) && response?.ready) {
                websiteState = response;
                currentTab = tab.id;
            }
        };

        const homeAssistantConn = await chrome.storage.local.get(["url", "token"]);
        const state = await getSensorState(homeAssistantConn, "trandelion");
        // Use a in-between Enable/Disable state from home assistant to not block state change from the browser
        if (currentTab !== undefined) {
            if (websiteState.button_state && state == "Disable") {
                await chrome.tabs.sendMessage(currentTab, { action: state });
            } else if (!websiteState.button_state && state == "Enable") {
                await chrome.tabs.sendMessage(currentTab, { action: state });
            }
        } else {
            if (state == "Enable") {
                chrome.tabs.create({ url: "https://trandelion.com/mytrandelion/", active: true });
            }
        }

        await updateSensorState(homeAssistantConn, "trandelion", "Trandelion", websiteState, currentTab);
    });
});