import * as os from 'os';
import { exec, ExecException } from "child_process";
import { powerMonitor } from "electron";

const batteryLevel = require('battery-level');

export abstract class BatteryUtils {
    
    public static async isOnBatteryPower(): Promise<boolean> {
        const onBattery = powerMonitor.isOnBatteryPower();

        if (!onBattery && os.platform() == 'linux') {
            return await new Promise<boolean>((resolve) => {
                exec("upower -i $(upower -e | grep 'battery') | grep 'state'", (error: ExecException | null, stdout: string) => {
                    if (error) {
                        console.error(`isOnBatteryPower(): ${error.message}`);
                        resolve(false);
                        return;
                    }
            
                    const isOnBattery = stdout.includes("discharging");
                    resolve(isOnBattery);
                });
            });
        }

        return onBattery;
    }

    public static async getLevel(): Promise<number> {
        try {
            return batteryLevel();
        }
        catch(error: any) {
            console.error(error);
            return -1;
        }
    }
}