// degree -> radian 변환
const deg2rad = (deg) => {
    return deg * (Math.PI / 180);
}
const rad2deg = (rad) => {
    return rad * (180 / Math.PI);
}
// 좌표간 거리계산
const getDistanceFromCoordByMeter = (coord1, coord2) => {
    const R = 6371; // Radius of the earth in km
    const dLat = deg2rad(coord2[0] - coord1[0]);  // deg2rad below
    const dLon = deg2rad(coord2[1] - coord1[1]);
    const a = Math.sin(dLat / 2) * Math.sin(dLat / 2) + Math.cos(deg2rad(coord1[0])) * Math.cos(deg2rad(coord2[0])) * Math.sin(dLon / 2) * Math.sin(dLon / 2);
    const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    // var d = R * c; // Distance in km
    const d = R * c * 1000; // Distance in m
    return d;
}
// 두 좌표사이 특정 거리만큼의 좌표 추출
const getCoordsFormBetweenCoord = (coord1, coord2, dist) => {
    // console.log('init ===> ', {coord1, coord2, dist})
    const r = [];
    // 처음 좌표
    r.push(coord1);
    // 중간 좌표
    const totalDist = getDistanceFromCoordByMeter(coord1, coord2);
    const dx = coord2[0] - coord1[0];
    const singX = dx < 0 ? -1 : 1;
    const dy = coord2[1] - coord1[1];
    const singY = dy < 0 ? -1 : 1;
    const m = dy / dx;
    const rad = Math.atan(m)

    const currentTotalDist = Math.sqrt((dx ** 2) + (dy ** 2))
    const currentDivDist = (dist * currentTotalDist) / totalDist;
    const div = Math.floor(currentTotalDist / currentDivDist);

    for (let i = 1; i <= div; i++) {
        const currentDist = currentDivDist * i;
        let x = coord1[0];
        let y = coord1[1];
        if (dx == 0) {
            y += currentDist * singY;
        } else if (dy == 0) {
            x += currentDist * singX;
        } else {
            x += Math.cos(rad) * currentDist;
            y += Math.sin(rad) * currentDist;
        }
        r.push([x, y])
    }
    // 마지막 좌표
    r.push(coord2)
    return r;
}

const dumyData = {
    "authKey": "1cc2e08e-0c5c-43b2-8d4d-cddd3de558e3",
    "terminalId": "SANDBOX-01",
    "command": "SANDBOX",
    "body": [
        {
            "objectId": "JAL497",
            "lat": 37.52097,
            "lon": 126.6146,
            "elevType": "M",
            "elev": 125.4,
            "speedType": "KM",
            "speed": 145.8,
            "heading": 227.94,
            "terminalRcvDt": "20210629173145",
            "betteryLevel": 91,
            "betteryVoltage": 50,
            "dronStatus": "TAKEOFF",
            "moveDistance": 120,
            "moveDistanceType": "M",
            "sensorCo": 100.11,
            "sensorSo2": 200.22,
            "sensorNo2": 300.33,
            "sensorO3": 400.44,
            "sensorDust": 500.55
        }
    ]
}

module.exports = {getDistanceFromCoordByMeter, deg2rad, getCoordsFormBetweenCoord, dumyData}


const test = () => {
    const coord1 = [37.5210, 126.6082];
    // const coord2 = [37.5210, 126.6057]; // x 절편
    const coord2 = [37.5200, 126.6082]; // y 절편
    // const coord2 = [37.5220, 126.6057]; // 일반
    const r = getCoordsFormBetweenCoord(coord1, coord2, 10)
    console.log(r)
    for (let i = 1; i < r.length; i++) {
        const dist = getDistanceFromCoordByMeter(r[i-1], r[i]);
        console.log(dist)
    }
}

// test();

const test2 = () => {
    let m = 10.5 / 14
    console.log(3 / 4, 13.5 / 18, (13.5 - 3) / (18 - 4))
    let rad = Math.atan(m);
    let tan = Math.tan(rad)
    let cos = Math.cos(rad)
    let sin = Math.sin(rad)
    console.log({rad, tan, cos, sin})
    let x = Math.cos(rad) * 15
    let y = Math.sin(rad) * 15
    console.log({x, y})

}
// test2();